阅读说明：本技术 水过滤膜装置和制备方法 (Water filtration membrane device and method of making ) 是由 李昆洲 聂子淞 于 2019-08-21 设计创作，主要内容包括：包括具有亲水性官能团的氧化石墨烯的滤水组合物、膜、装置和制造方法。公开了一种包括氧化石墨烯的组合物,所述氧化石墨烯的平均粒径不大于约1微米且氧原子百分数至少约为30％,公开了包括所述组合物的膜、包括所述膜的水可渗透的装置、使用所述组合物制作所述膜的方法以及制备所述组合物的几种方法。(Drainage compositions, membranes, devices, and methods of manufacture including graphene oxide with hydrophilic functional groups. Disclosed are compositions comprising graphene oxide having an average particle size of no greater than about 1 micron and an atomic percent of oxygen of at least about 30, membranes comprising the compositions, water-permeable devices comprising the membranes, methods of making the membranes using the compositions, and several methods of making the compositions.)

1. A composition comprising graphene oxide, wherein the graphene oxide has an average particle size of no greater than about 1 micron, and,

the graphene oxide has an atomic percent of oxygen of at least about 30%.

2. The composition of claim 1, wherein the graphene oxide has an average particle size of no greater than about 100 nm.

3. The composition of claim 1 or 2, wherein the graphene oxide has an average particle size of about 10 nanometers to about 100 nanometers.

4. The composition of any one of claims 1-3, wherein the atomic percent of oxygen is at least 35%.

5. The composition of claim 4, wherein the atomic percent of oxygen is from about 35% to about 50%.

6. The composition of any one of claims 1-5, wherein the graphene oxide has an absorbance level at a wavelength of 230 nanometers that is lower than graphene oxide having an average particle size of greater than 1 micrometer.

7. The composition of claim 6, wherein the graphene oxide has an absorbance level at a wavelength of 230 nanometers that is at least 20% lower than the graphene oxide having an average particle size of greater than 1 micrometer.

8. The composition of any one of claims 1-7, wherein the graphene oxide has an absorbance level at a wavelength of 230 nanometers that is lower than graphene oxide having an atomic percent of oxygen of less than 30%.

9. The composition as claimed in claim 8, wherein the graphene oxide has an absorbance level at 230 nm that is at least 20% lower than graphene oxide having an atomic percent of oxygen of less than 30%.

10. The composition of any one of claims 1-9, wherein the graphene oxide has a lower absorbance level at a wavelength of 230 nanometers than graphene oxide made with a lower amount of sulfuric acid.

11. The composition as claimed in claim 10, wherein the graphene oxide has an absorbance level at 230 nm that is at least 20% lower than the graphene oxide prepared with a lower amount of sulfuric acid.

12. The composition of any one of claims 1-11, further comprising sulfuric acid.

13. The composition of any one of claims 1-12, further comprising an oxidizing agent.

14. The composition of claim 13, wherein the oxidizing agent comprises oxygen (O)₂) Ozone (O)₃) Hydrogen peroxide (H)₂O₂) Fenton's reagent, fluorine (F)₂) Chlorine (Cl)₂) Bromine (Br)₂) Iodine (I)₂) Nitric acid (HNO)₃) Sulfuric acid (H)₂SO₄) Peroxodisulfuric acid (H)₂S₂O₈) Peroxomonosulfuric acid (H)₂SO₅) Chlorite, chlorate, perchlorate, hypochlorite, bleach (NaClO), chromic acid, dichromic acid, chromium trioxide, pyridinium chlorochromate (PCC), potassium permanganate, sodium perborate, nitrous oxide (N)₂O), nitrogen dioxide (NO)₂) Dinitrogen tetroxide (N)₂O₄) Potassium nitrate (KNO3), sodium bismuthate, or any combination thereof.

15. The composition of claim 14, wherein the oxidizing agent comprises hydrogen peroxide.

16. The composition of claim 14, wherein the oxidizing agent comprises potassium permanganate.

17. The composition of any one of claims 1-16, further comprising an organic solvent.

18. The composition of claim 17, wherein the organic solvent comprises a non-polar solvent, a polar aprotic solvent, a polar protic solvent, or any combination thereof.

19. The composition of claim 18, wherein the non-polar solvent comprises pentane, cyclopentane, hexane, cyclohexane, benzene, toluene, 1, 4-dioxane, chloroform, diethyl ether, Dichloromethane (DCM), or any combination thereof.

20. The composition of claim 18, wherein the polar aprotic solvent comprises Tetrahydrofuran (THF), ethyl acetate, acetone, Dimethylformamide (DMF), acetonitrile (MeCN), dimethyl sulfoxide (DMSO), nitromethane, propylene carbonate, or any combination thereof.

21. The composition of claim 18, wherein the polar protic solvent comprises formic acid, n-butanol, Isopropanol (IPA), n-propanol, ethanol, methanol, acetic acid, or any combination thereof.

22. The composition of claim 17, wherein the organic solvent comprises N, N-Dimethylacetamide (DMAC), N-methyl-2-pyrrolidone (nano-P), Dimethylformamide (DMF), or any combination thereof.

23. The composition as claimed in claim 17, wherein the organic solvent comprises an alkane and/or a cycloalkanone.

24. The composition as recited in claim 23, wherein the cycloalkanone comprises hexane, isoparaffin, light alkylated naphtha, cyclohexanone, or any combination thereof.

25. The composition of any one of claims 1-24, further comprising an inorganic solvent.

26. The composition of any one of claims 1-25, further comprising a polymer.

27. The composition as recited in claim 26 wherein the polymer comprises polyvinylidene fluoride (PVDF).

28. The composition of claim 27, wherein the polyvinylidene fluoride (PVDF) has an average molecular weight of at least about 100000.

29. The composition as claimed in claim 28 wherein the polyvinylidene fluoride (PVDF) has an average molecular weight of about 300000 to about 700000.

30. The composition of any one of claims 27-29, wherein the polyvinylidene fluoride (PVDF) comprises about 10% to about 30% (w/w) of the composition.

31. The composition of any one of claims 26-30, wherein the polymer comprises poly (vinyl pyrrolidone) (PVP molecular weight 8-2000kDa), triethyl phosphate (TEP), Ethylene Glycol (EG), perfluorosulfonic acid, or any combination thereof.

32. The composition of any one of claims 26-31, wherein the polymer comprises from about 1% to about 8% (w/w) of the composition.

33. The composition of any one of claims 1-32, further comprising polyvinyl alcohol (PVA), glutaraldehyde, methylene chloride, Octadecyltrichlorosilane (ODS), hydrochloric acid (HCl), or any combination thereof.

34. The composition of any one of claims 1-33, further comprising Triethylamine (TEA), camphorsulfonic acid (CSA), dimethyl sulfoxide (DMSO), metaphenylene diamine (MPD), 2-ethyl-1, 3-hexanediol (EHD), sodium lauryl sulfate (SLES), or any combination thereof.

35. The composition of claim 34, comprising from about 1% to about 4% (w/w) Triethylamine (TEA).

36. The composition of claim 34, comprising about 1% to about 5% (w/w) camphorsulfonic acid (CSA).

37. The composition of claim 34, comprising about 1% to about 2% (w/w) dimethyl sulfoxide (DMSO).

38. The composition of claim 34, comprising about 0.2% to about 3% (w/w) metaphenylene diamine (MPD).

39. The composition of claim 34, comprising about 0.1% to about 0.4% (w/w) 2-ethyl-1, 3-hexanediol (EHD).

40. The composition of claim 34, comprising from about 0.1% to about 0.4% (w/w) sodium lauryl sulfate (SLES).

41. The composition of any one of claims 1-40, further comprising 1,3, 5-benzenetricarboxylic acid chloride (TMC), tributyl phosphate (TBP), or any combination thereof.

42. The composition of claim 41, comprising from about 0.01% to about 0.2% (w/w) 1,3, 5-benzenetricarboxylic acid chloride (TMC).

43. The composition of claim 41, comprising from about 0.1% to about 0.5% (w/w) tributyl phosphate (TBP).

44. The composition of any one of claims 1-43, further comprising a carboxylic acid, oxalic acid, citric acid, phosphoric acid, benzoic acid, dihydroxybenzene, dopamine, or any combination thereof.

45. The composition of any one of claims 1-44, further comprising Polyethersulfone (PES).

46. The composition as in claim 45 wherein the polyethersulfone has an average molecular weight of at least about 20000.

47. The composition as claimed in claim 46 wherein the polyethersulfone has an average molecular weight of from about 45000 to about 68000.

48. The composition according to one of claims 45-47, wherein the polyethersulfone comprises between about 15% and about 30% (w/w) of the composition.

49. The composition of any one of claims 1-48, further comprising a sugar.

50. The composition of claim 49, comprising about 1% to about 60% (w/w) of the sugar.

51. The composition of claim 49, wherein the sugar comprises a monosaccharide, a disaccharide, a polysaccharide, or any combination thereof.

52. The composition of claim 49, wherein the sugar comprises glucose, fructose, sucrose, or any combination thereof.

53. A film comprising the composition of any one of the preceding claims.

54. The membrane of claim 53, further comprising a support layer.

55. The film of claim 54, wherein the support layer comprises a non-woven fabric.

56. The film of claim 55, wherein the nonwoven comprises a polypropylene nonwoven.

57. The film of any one of claims 53-56, having a water contact angle of less than about 80 °.

58. The film of claim 57, wherein the water contact angle is from about 40 ° to about 60 °.

59. The membrane of any one of claims 53-58, having an average surface pore size of at least 1 nanometer.

60. The membrane of claim 59, wherein the average surface pore size is from about 2 nanometers to about 8 nanometers.

61. The membrane of claim 59, wherein the average surface pore size is from about 10 nanometers to about 80 nanometers.

62. The membrane of any one of claims 53-61, having a porosity of at least 50%.

63. The membrane of claim 62, wherein the porosity is from about 70% to about 85%.

64. The membrane of any one of claims 53-63, having a water permeability of at least 20 LMH/bar.

65. The membrane of claim 64, wherein the water permeability is about 50LMH/bar to about 70 LMH/bar.

66. The membrane of claim 64, having a water permeability of at least 200 LMH/bar.

67. The membrane of claim 64, wherein the water permeability is about 500LMH/bar to about 600 LMH/bar.

68. The membrane of any one of claims 53-67, having a water permeability of at least 2LMHs/bar at a pressure of 15.5bar using 2000ppm sodium chloride solution.

69. The membrane of any one of claims 53-68, having a salt rejection of at least 80%.

70. A water permeable device comprising the membrane of any one of claims 53-69.

71. A method, comprising:

a) providing graphite powder;

b) providing an oxidizing agent; and

c) mixing the graphite powder with the oxidant to produce a composition comprising graphene oxide, wherein the graphene oxide has an average particle size of no more than about 1 micron and an atomic percent of oxygen of at least about 30%.

72. The method of claim 71, wherein the composition comprising graphene oxide is the composition of any one of claims 1-52.

73. The method of claim 71 or 72, further comprising milling a graphite-containing composition to produce the graphite powder, wherein the graphite powder has an average particle size of not greater than about 2 microns.

74. The method of any one of claims 71-73, wherein the oxidant comprises oxygen (O)₂) Ozone (O)₃) Hydrogen peroxide (H)₂O₂) Fenton's reagent, fluorine (F)₂) Chlorine (Cl)₂) Bromine (Br)₂) Iodine (I)₂) Nitric acid (HNO)₃) Sulfuric acid (H)₂SO₄) Peroxodisulfuric acid (H)₂S₂O₈) Peroxomonosulfuric acid (H)₂SO₅) Chlorite, chlorate, perchlorate, hypochlorite, bleach (NaClO), chromic acid, dichromic acid, chromium trioxide, pyridinium chlorochromate (PCC), potassium permanganate, sodium perborate, nitrous oxide (N)₂O), nitrogen dioxide (NO)₂) Dinitrogen tetroxide (N)₂O₄) Potassium nitrate (KNO)₃) Sodium bismuthate or any combination thereof.

75. The method of claim 74, wherein the oxidizing agent comprises sulfuric acid, potassium permanganate, hydrogen peroxide, or any combination thereof.

76. The method of any one of claims 71-75, further comprising mixing the composition comprising graphene oxide with an organic solvent to form a mixture.

77. The method of claim 76, wherein the organic solvent comprises a non-polar solvent, a polar aprotic solvent, a polar protic solvent, or any combination thereof.

78. The method of claim 77, wherein the non-polar solvent comprises pentane, cyclopentane, hexane, cyclohexane, benzene, toluene, 1, 4-dioxane, chloroform, diethyl ether, Dichloromethane (DCM), or any combination thereof.

79. The method of claim 77, wherein the polar aprotic solvent comprises Tetrahydrofuran (THF), ethyl acetate, acetone, Dimethylformamide (DMF), acetonitrile (MeCN), dimethyl sulfoxide (DMSO), nitromethane, propylene carbonate, or any combination thereof.

80. The method of claim 77, wherein the polar protic solvent comprises formic acid, n-butanol, Isopropanol (IPA), n-propanol, ethanol, methanol, acetic acid, or any combination thereof.

81. The method of any one of claims 76-80, further comprising separating solids comprising graphene oxide from the mixture.

82. The method of claim 81, wherein the separating step comprises fractionation, centrifugation, filtration, or any combination thereof.

83. The method of claim 82, wherein the filtering uses a pressure filter or electrodialysis.

84. The method of any one of claims 81-83, further comprising washing the solid comprising graphene oxide with a second organic solvent.

85. The method of claim 84, wherein the second organic solvent comprises ethanol, methanol, or any combination thereof.

86. The method of any one of claims 81-85, further comprising drying the solid comprising graphene oxide.

87. A method, comprising:

a) heating the sugar solution to produce a solid powder; and

b) mixing the solid powder with an oxidizing agent to produce a composition comprising graphene oxide, wherein the graphene oxide has an average particle size of no more than about 1 micron and an atomic percent of oxygen of at least about 30%.

88. The method of claim 87, wherein the composition comprising graphene oxide is the composition of any one of claims 1-52.

89. The method of claim 87 or 88, wherein the sugar comprises from about 1% to about 60% (w/w) of the composition.

90. The method of any one of claims 87 to 89, wherein the sugar comprises a monosaccharide, a disaccharide, a polysaccharide, or any combination thereof.

91. The method of any one of claims 87 to 90 wherein the sugar comprises glucose, fructose, sucrose or any combination thereof.

92. The method of any one of claims 87-91, comprising heating the sugar solution to at least 100 ℃.

93. The method of claim 92 comprising heating the sugar solution to 180-220 ℃.

94. The method of any of claims 87-93, comprising heating the sugar solution at a pressure greater than 2 atm.

95. The method of claim 94, comprising heating the sugar solution at a pressure of 12-20 atm.

96. The method of any one of claims 87 to 95 wherein the oxidant comprises oxygen (O)₂) Ozone (O)₃) Hydrogen peroxide (H)₂O₂) Fenton's reagent, fluorine (F)₂) Chlorine (Cl)₂) Bromine (Br)₂) Iodine (I)₂) Nitric acid (HNO)₃) Sulfuric acid (H)₂SO₄) Peroxodisulfuric acid (H)₂S₂O₈) Peroxomonosulfuric acid (H)₂SO₅) Chlorite, chlorate, perchlorate, hypochlorite, bleach (NaClO), chromic acid, sulfuric,Dichromic acid, chromium trioxide, pyridinium chlorochromate (PCC), potassium permanganate, sodium perborate, nitrous oxide (N)₂O), nitrogen dioxide (NO)₂) Dinitrogen tetroxide (N)₂O₄) Potassium nitrate (KNO)₃) Sodium bismuthate or any combination thereof.

97. The method of claim 96, wherein the oxidizing agent comprises sulfuric acid, potassium permanganate, hydrogen peroxide, or any combination thereof.

98. The method of any one of claims 87-97, further comprising separating solids comprising graphene oxide from the oxidant.

99. The method of claim 98, wherein the separating step comprises fractionation, centrifugation, filtration, or any combination thereof.

100. The method of claim 99, wherein the filtering uses a pressure filter or electrodialysis.

101. The method of any one of claims 98-100, further comprising washing the solid comprising graphene oxide with a second organic solvent.

102. The method of claim 101, wherein the second organic solvent comprises ethanol, methanol, or any combination thereof.

103. The method of any one of claims 98-102, further comprising drying the solid comprising graphene oxide.

104. A method, comprising:

a) mixing a sugar component with an acidic component; and

b) heating the sugar component to produce a composition comprising graphene oxide, wherein the graphene oxide has an average particle size of no more than about 1 micron and an atomic percent of oxygen of at least about 30%.

105. The method of claim 104, wherein the composition comprising graphene oxide is the composition of any one of claims 1-52.

106. The method of claim 104 or 105, wherein the acidic component comprises carboxylic acid, oxalic acid, citric acid, phosphoric acid, benzoic acid, dihydroxybenzene, dopamine, or any combination thereof.

107. The method as set forth in any one of claims 104 to 106 wherein the sugar comprises from about 1% to about 60% (w/w) of the composition comprising graphene oxide.

108. The method of any one of claims 104-107, wherein the sugar comprises a monosaccharide, a disaccharide, a polysaccharide, or any combination thereof.

109. The method of claim 108, wherein the sugar comprises glucose, fructose, sucrose, or any combination thereof.

110. The method as set forth in any one of claims 104-109 comprising heating the sugar component to at least 100 ℃.

111. The method as set forth in claim 110 comprising heating the sugar component to 180-220 ℃.

112. The method as claimed in any one of claims 104-111, comprising heating the sugar component at a pressure of greater than 2 atm.

113. The method of claim 112, comprising heating the sugar component at a pressure of 12-20 atm.

114. The method as set forth in any one of claims 104-113, further comprising separating a solid comprising graphene oxide from the acidic component.

115. The method of claim 114, wherein said separating step comprises fractionation, centrifugation, filtration, or any combination thereof.

116. The method as recited in claim 115 wherein the filtering uses a pressure filter or electrodialysis.

117. The method as set forth in any one of claims 114-116, further comprising washing the solid comprising graphene oxide with a second organic solvent.

118. The method of claim 117, wherein the second organic solvent comprises ethanol, methanol, or any combination thereof.

119. The method as set forth in any one of claims 114-118, further comprising drying the solid comprising graphene oxide.

120. A method, comprising:

a) mixing graphite powder with a first oxidant to produce a first composition comprising graphene oxide; and

b) mixing the first composition comprising graphene oxide with a second oxidant to produce a second composition comprising graphene oxide, wherein the graphene oxide of the second composition has an average particle size of no more than about 1 micron and an atomic percent of oxygen of at least about 30%.

121. The method of claim 120, wherein the second composition comprising graphene oxide is the composition of any one of claims 1-52.

122. The method of claim 120 or 121, wherein said first oxidizing agent comprises oxygen (O)₂) Ozone (O)₃) Hydrogen peroxide (H)₂O₂) Fenton's reagent, fluorine (F)₂) Chlorine (Cl)₂) Bromine (Br)₂) Iodine (I)₂) Nitric acid (HNO)₃) Sulfuric acid (H)₂SO₄) Peroxodisulfuric acid (H)₂S₂O₈) Peroxomonosulfuric acid (H)₂SO₅) Chlorite, chlorate, perchlorate, hypochlorite, bleach (NaClO), chromic acid, dichromic acid, chromium trioxide, pyridinium chlorochromate (PCC), potassium permanganate, sodium perborate, nitrous oxide (N)₂O), nitrogen dioxide (NO)₂) Dinitrogen tetroxide (N)₂O₄) Potassium nitrate (KNO)₃) Sodium bismuthate or any combination thereof.

123. The method of claim 122, wherein the first oxidizing agent comprises sulfuric acid, potassium permanganate, hydrogen peroxide, or any combination thereof.

124. The method as recited in any one of claims 120-123, further comprising separating the first composition comprising graphene oxide from the first oxidizing agent.

125. The method of claim 124, wherein the separating step comprises fractionation, centrifugation, filtration, or any combination thereof.

126. The method as recited in claim 125 wherein the filtering uses a pressure filter or electrodialysis.

127. The method as set forth in any one of claims 120-126, wherein the second oxidizing agent comprises sulfuric acid, potassium permanganate, hydrogen peroxide, or any combination thereof.

128. The method of any one of claims 120-127, further comprising separating the second composition comprising graphene oxide from the second oxidant.

129. The method of any one of claims 120-128, further comprising washing the second composition comprising graphene oxide with a second organic solvent.

130. The method of claim 129, wherein the second organic solvent comprises ethanol, methanol, or any combination thereof.

131. The method of any one of claims 120-130, further comprising drying the second composition comprising graphene oxide.

132. A method of making a film comprising mixing the composition of any one of the preceding claims with an organic solvent.

133. The method of claim 132, wherein the organic solvent comprises N, N-Dimethylacetamide (DMAC), N-methyl-2-pyrrolidone (nano-P), Dimethylformamide (DMF), or any combination thereof.

134. The method as recited in claim 132, wherein the organic solvent comprises an alkane and/or a cycloalkanone.

135. The method of claim 134, wherein the cycloalkanone comprises hexane, isoparaffin, light alkylated naphtha, cyclohexanone, or any combination thereof.

136. The method as set forth in any one of claims 132-135, further comprising mixing the composition with an inorganic solvent.

137. The method of any one of claims 132-136, further comprising dispersing the composition in the organic solvent using a high pressure homogenizer to produce an organic solution comprising graphene oxide.

138. The method of claim 136 or 137, further comprising dispersing the composition in the inorganic solvent using a high pressure homogenizer to produce an inorganic solution comprising graphene oxide.

139. The method as set forth in any one of claims 137-138, wherein the dispersing is carried out at a pressure of 10000psi or more.

140. The method of claim 139 wherein the dispersing is performed at a pressure of 15000-.

141. The method as set forth in any one of claims 137-140, wherein the dispersing is performed at least 3 times.

142. The method as recited in any one of claims 132-141, further comprising mixing the organic solution comprising graphene oxide with a polymer to form a polymer solution.

143. The method of claim 142, wherein the polymer comprises polyvinylidene fluoride (PVDF).

144. The method of claim 143, wherein the polyvinylidene fluoride (PVDF) has an average molecular weight of at least about 100000.

145. The method of claim 144, wherein the polyvinylidene fluoride has an average molecular weight of about 300000 to 700000.

146. The method as claimed in claim 143-145, wherein the polyvinylidene fluoride (PVDF) is about 10% to about 30% (w/w).

147. The method of any one of claims 142-146, wherein the polymer comprises Polyethersulfone (PES).

148. The method of claim 147, wherein the polyethersulfone has an average molecular weight of at least about 20000.

149. The method of claim 147 or 148, wherein the average molecular weight of the polyethersulfone is between about 45000 and 68000.

150. The method of any one of claims 147-149 wherein the polyethersulfone is present in an amount of about 15% to about 30% (w/w).

151. The method of any one of claims 142-150, wherein the polymer comprises poly (vinyl pyrrolidone) (PVP molecular weight 8-2000kDa), triethyl phosphate (TEP), Ethylene Glycol (EG), perfluorosulfonic acid, or any combination thereof.

152. The method of claim 151, wherein the polymer is about 1% to about 8% (w/w).

153. The method of any one of claims 142-152, further comprising heating the polymer solution to 60-70 ℃.

154. The method of any one of claims 142-153, further comprising mixing the polymer solution with water using a spinning apparatus.

155. The method of any one of claims 142-152, further comprising mixing the polymer solution with a solution comprising polyvinyl alcohol (PVA), glutaraldehyde, methylene chloride, Octadecyltrichlorosilane (ODS), hydrochloric acid (HCl), or any combination thereof.

156. The method of any one of claims 142-155, further comprising mixing the polymer solution with a glycerol solution to form a hollow fiber membrane.

157. The method of any one of claims 142-156, wherein the polymer comprises polysulfone.

158. The method of claim 157 wherein the polysulfone has an average molecular weight of at least about 50000.

159. The method of claim 157 or 158, wherein the polysulfone has an average molecular weight of about 67000 to about 81000.

160. The method of any one of claims 157-159, wherein the polysulfone is about 10% to about 30% (w/w).

161. The method of any one of claims 142-160, wherein the polymer comprises Polysulfone (PSU), Polyetherimide (PEI), Polyethersulfone (PES), or any combination thereof.

162. The method of any one of claims 142-161, further comprising coating a support layer with the polymer solution.

163. The method of any one of claims 142-162, further comprising mixing the inorganic solution comprising graphene oxide with Triethylamine (TEA), camphorsulfonic acid (CSA), dimethyl sulfoxide (DMSO), meta-phenylenediamine (MPD), 2-ethyl-1, 3-hexanediol (EHD), sodium lauryl sulfate (SLES), or any combination thereof.

164. The method of claim 163, wherein the Triethylamine (TEA) comprises about 1% to about 4% (w/w) of the composition.

165. The method of claim 163 or 164, wherein said camphorsulfonic acid (CSA) comprises from about 1% to about 5% (w/w) of the composition.

166. The method of any one of claims 163-165 wherein the dimethyl sulfoxide (DMSO) comprises from about 1% to about 2% (w/w) of the composition.

167. The method of any one of claims 163-166, wherein metaphenylene diamine (MPD) comprises from about 0.2% to about 3% (w/w) of the composition.

168. The method of any one of claims 163-167 wherein the 2-ethyl-1, 3-hexanediol (EHD) comprises about 0.1% to about 0.4% (w/w) of the composition.

169. The method of any one of claims 163-168 wherein the sodium lauryl sulfate (SLES) comprises from about 0.1% to about 0.4% (w/w) of the composition.

170. The method of any one of claims 137-169, further comprising mixing the organic solution comprising graphene oxide with 1,3, 5-benzenetricarbonyl chloride (TMC), tributyl phosphate (TBP), or any combination thereof.

171. The method as recited in claim 170, wherein said 1,3, 5-benzenetricarboxylic acid chloride (TMC) comprises from about 0.01% to about 0.1% (w/w) of the composition.

172. The method of claim 170 or 171, wherein the tributyl phosphate (TBP) comprises from about 0.1% to about 0.5% (w/w) of the composition.

173. A membrane made according to the method of any one of claims 132-172.

Technical Field

The present disclosure relates generally to devices and methods for water treatment, and more particularly, to water filtration membranes, devices, and methods of manufacture including graphene oxide with hydrophilic functional groups.

Background

Membrane technology is preferred over other technologies in water treatment applications such as disinfection, distillation or media filtration because it generally does not require regeneration of chemical additives, heat input or spent media. However, the operating costs of membrane technology are relatively high due to the short service time of the membrane and the rapid decay of performance caused by membrane fouling. When the pores in the membrane are blocked or plugged, or when a layer of polarization concentration or cake is formed on the membrane surface, the water flux through the membrane will be significantly reduced.

The antifouling properties of conventional water filtration membranes remain to be improved. Since the membrane material has hydrophobicity, contaminants or biological organisms are easily attached to the surface of the membrane. By adding graphene oxide having a hydrophilic functional group to the water filtration membrane, the membrane can be effectively prevented from fouling by increasing the hydrophilicity of the membrane. Graphene oxide obtained by conventional methods is typically oversized or non-uniformly dispersed, resulting in a non-uniform pore size and/or porosity distribution of the membrane. In addition, the graphene oxide prepared by the conventional process includes insufficient hydrophilic functional groups, which limits the hydrophilicity of the membrane. These factors are major bottlenecks that need to be addressed before commercial value can be achieved including graphene integrated water filtration membranes.

Disclosure of Invention

Several new methods of synthesizing oxygen-rich graphene oxide, which may be a single layer graphene oxide including a high percentage of hydrophilic functional groups, are disclosed. Methods of mixing and dispersing the oxygen-enriched graphene oxide into various water filtration membrane products with high uniformity are also disclosed. These methods can significantly improve the hydrophilicity and water flux of the membrane. They can also improve the antifouling and anti-biofouling properties of the membranes, thereby extending the membrane cleaning time and reducing the cost of water treatment. In addition, the method using saccharides as a raw material provides an environmentally friendly, impurity-free, and low-cost method for mass production of graphene oxide.

Also disclosed are compositions, membranes, devices, and methods of making water filtration systems comprising graphene oxide.

In one aspect, a composition is disclosed that includes graphene oxide, wherein the graphene oxide has an average particle size of no more than about 2 microns and an atomic percent of oxygen of at least about 30%. In some embodiments, the graphene oxide has an average particle size of no more than about 1 micron. In some embodiments, the graphene oxide has an average particle size of about 0.001 to 2 microns. In some embodiments, the graphene oxide has an average particle size of at least about 0.001 microns. In some embodiments, the graphene oxide has an average particle size of at most about 2 microns. In some embodiments, the graphene oxide has an average particle size of at most about 1.5 microns. In some embodiments, the graphene oxide has an average particle size of at most about 1 micron. In some embodiments, the graphene oxide has an average particle size of at most about 0.5 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.2 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.1 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.05 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.01 microns. In some embodiments, the graphene oxide has an average particle size of from about 2 microns to about 1.5 microns, from about 2 microns to about 1 micron, from about 2 microns to about 0.5 microns, from about 2 microns to about 0.2 microns, from about 2 microns to about 0.1 microns, from about 2 microns to about 0.05 microns, from about 2 microns to about 0.01 microns, from about 2 microns to about 0.005 microns, from about 2 microns to about 0.001 microns, from about 1.5 microns to about 1 micron, from about 1.5 microns to about 0.5 microns, from about 1.5 microns to about 0.2 microns, from about 1.5 microns to about 0.1 microns, from about 1.5 microns to about 0.05 microns, from about 1.5 microns to about 0.01 microns, from about 1.5 microns to about 0.005 microns, from about 1.5 microns to about 0.001 microns, from about 1 microns to about 0.5 microns, from about 1 microns to about 0.2 microns, from about 1 micron to about 1.001 microns, from about 0.05 microns, from about 1 microns to about 0.005 microns, from about 0.05 microns, from about 1.0 microns to about 0.05 microns, from about 1.0 microns to about 0.001 microns, from about 0.05 microns, from about 1.05, About 0.5 microns to about 0.2 microns, about 0.5 microns to about 0.1 microns, about 0.5 microns to about 0.05 microns, about 0.5 microns to about 0.01 microns, about 0.5 microns to about 0.005 microns, about 0.5 microns to about 0.001 microns, about 0.2 microns to about 0.1 microns, about 0.2 microns to about 0.05 microns, about 0.2 microns to about 0.01 microns, about 0.2 microns to about 0.005 microns, about 0.2 microns to about 0.001 microns, about 0.1 microns to about 0.05 microns, about 0.1 microns to about 0.01 microns, about 0.1 microns to about 0.005 microns, about 0.1 microns to about 0.001 microns, about 0.05 microns to about 0.01 microns, about 0.05 microns to about 0.005 microns, about 0.05 microns to about 0.001 microns, about 0.001 microns to about 0.01 microns, about 0.001 microns to about 0.005 microns, or about 0.5 microns to about 0.001 microns. In some embodiments, the graphene oxide has an average particle size of about 2 microns, about 1.5 microns, about 1 micron, about 0.5 microns, about 0.2 microns, about 0.1 microns, about 0.05 microns, about 0.01 microns, about 0.005 microns, or about 0.001 microns. In some embodiments, the average particle size of the graphene oxide is not greater than about 100 nanometers. In some embodiments, the average particle size of the graphene oxide is from about 10 nanometers to about 100 nanometers.

In some embodiments, the atomic percent of oxygen of the graphene oxide is from about 30% to about 70%. In some embodiments, the atomic percent of oxygen of the graphene oxide is at least about 30%. In some embodiments, the atomic percent of oxygen of the graphene oxide is at most about 70%. In some embodiments, the atomic percent of oxygen of the graphene oxide is from about 30% to about 35%, from about 30% to about 40%, from about 30% to about 45%, from about 30% to about 50%, from about 30% to about 55%, from about 30% to about 60%, from about 30% to about 65%, from about 30% to about 70%, from about 35% to about 40%, from about 35% to about 45%, from about 35% to about 50%, from about 35% to about 55%, from about 35% to about 60%, from about 35% to about 65%, from about 35% to about 70%, from about 40% to about 45%, from about 40% to about 50%, from about 40% to about 55%, from about 40% to about 60%, from about 40% to about 65%, from about 40% to about 70%, from about 45% to about 50%, from about 45% to about 55%, from about 45% to about 60%, from about 45% to about 65%, from about 45% to about 70%, from about 50% to about 55%, from about 50% to about 60%, from about 50% to about 65%, from about 50% to about 70%, or, About 55% to about 60%, about 55% to about 65%, about 55% to about 70%, about 60% to about 65%, about 60% to about 70%, or about 65% to about 70%. In some embodiments, the graphene oxide has an atomic percent of oxygen of about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, or about 70%. In some embodiments, the atomic percent of oxygen is at least 35%. In some embodiments, the atomic percent of oxygen is from about 35% to about 50%.

In some embodiments, the graphene oxide has an absorbance level at a wavelength of 230 nanometers that is lower than graphene oxide having an average particle size of greater than 1 micrometer. For example, the absorbance level of graphene oxide at a wavelength of 230 nanometers may be at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% lower than the absorbance level of graphene oxide having an average particle size of greater than 1 micron. In some embodiments, the graphene oxide has an absorbance level at a wavelength of 230 nanometers that is lower than graphene oxide having an average particle size of greater than 2 microns. For example, the absorbance level of graphene oxide at a wavelength of 230 nanometers may be at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% lower than the absorbance level of graphene oxide having an average particle size of greater than 2 microns. In some embodiments, the graphene oxide has an absorbance level at a wavelength of 230 nanometers that is lower than graphene oxide having an average particle size of greater than 5 micrometers. For example, the absorbance level of graphene oxide at a wavelength of 230 nanometers may be at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% lower than the absorbance level of graphene oxide having an average particle size of greater than 5 microns. In some embodiments, the graphene oxide has an absorbance level at a wavelength of 230 nanometers that is lower than graphene oxide having an average particle size of greater than 10 micrometers. For example, the absorbance level of graphene oxide at a wavelength of 230 nanometers may be at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% lower than the absorbance level of graphene oxide having an average particle size of greater than 10 microns.

In some embodiments, the graphene oxide has an absorbance level at a wavelength of 230 nanometers that is less than that of graphene oxide having an atomic percent of oxygen of less than 30%. For example, the graphene oxide may have an absorbance level at 230 nm wavelength that is at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% lower than that of graphene oxide having an atomic percent of oxygen of less than 30%. In some embodiments, the graphene oxide has an absorbance level at a wavelength of 230 nanometers that is less than that of graphene oxide having an atomic percent of oxygen of less than 20%. For example, the graphene oxide may have an absorbance level at 230 nm wavelength that is at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% lower than that of graphene oxide having an atomic percent of oxygen of less than 20%. In some embodiments, the graphene oxide has an absorbance level at a wavelength of 230 nanometers that is less than 10% of the graphene oxide by atomic percent oxygen. For example, the graphene oxide may have an absorbance level at 230 nm wavelength that is at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% lower than that of graphene oxide having an atomic percent of oxygen of less than 10%.

In some embodiments, the graphene oxide has an absorbance level at a wavelength of 230 nanometers that is lower than with a lesser amount of H₂SO₄And (3) preparing the graphene oxide. For example, the graphene oxide may have an absorbance level at 230 nm wavelength that is at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% lower than graphene oxide made using a lesser amount of sulfuric acid.

In some embodiments, the composition further comprises sulfuric acid. In some embodiments, the composition further comprises an oxidizing agent. In some embodiments, the oxidant comprises oxygen (O)₂) Ozone (O)₃) Hydrogen peroxide (H)₂O₂) Fenton's reagent, fluorine (F)₂) Chlorine (Cl)₂) Bromine (Br)₂) Iodine (I)₂) Nitric acid (HNO)₃) Sulfuric acid (H)₂SO₄) Peroxodisulfuric acid (H)₂S₂O₈) Peroxomonosulfuric acid (H)₂SO₅) Chlorite, chlorate, perchlorate, hypochlorite, bleach (NaClO), chromic acid, dichromic acid, chromium trioxide, chromium pyridinium chlorochromate (PCC), permanganate, sodium perborate, nitrous oxide (N)₂O)、Nitrogen dioxide (NO)₂) Dinitrogen tetroxide (N)₂O₄) Potassium nitrate (KNO)₃) Sodium bismuthate or any combination thereof. In some embodiments, the oxidizing agent comprises hydrogen peroxide. In some embodiments, the oxidizing agent comprises potassium permanganate.

In some embodiments, the composition further comprises an organic solvent. In some embodiments, the organic solvent comprises a non-polar solvent, a polar aprotic solvent, a polar protic solvent, or any combination thereof. In some embodiments, the non-polar solvent comprises pentane, cyclopentane, hexane, cyclohexane, benzene, toluene, 1, 4-dioxane, chloroform, diethyl ether, Dichloromethane (DCM), or any combination thereof. In some embodiments, the polar aprotic solvent comprises Tetrahydrofuran (THF), ethyl acetate, acetone, Dimethylformamide (DMF), acetonitrile (MeCN), dimethyl sulfoxide (DMSO), nitromethane, propylene carbonate, or any combination thereof. In some embodiments, the polar protic solvent comprises formic acid, n-butanol, Isopropanol (IPA), n-propanol, ethanol, methanol, acetic acid, or any combination thereof. In some embodiments, the organic solvent comprises N, N-Dimethylacetamide (DMAC), N-methyl-2-pyrrolidone (nano-P), Dimethylformamide (DMF), or any combination thereof. In some embodiments, the organic solvent comprises an alkane and/or a cycloalkanone. In some embodiments, the cycloalkanone comprises hexane, isoparaffin, light alkylated naphtha, cyclohexanone, or any combination thereof.

In some embodiments, the composition further comprises an inorganic solvent.

In some embodiments, the composition further comprises a polymer. In some embodiments, the polymer comprises polyvinylidene fluoride (PVDF). In some embodiments, the polyvinylidene fluoride has an average molecular weight of about 50000 to about 1000000. In some embodiments, the polyvinylidene fluoride has an average molecular weight of at least about 50000. In some embodiments, the polyvinylidene fluoride has an average molecular weight of up to about 1000000. In some embodiments, the polyvinylidene fluoride has an average molecular weight of about 50000 to about 100000, about 50000 to about 300000, about 50000 to about 500000, about 50000 to about 700000, about 50000 to about 800000, about 50000 to about 1000000, about 100000 to about 300000, about 100000 to about 500000, about 100000 to about 700000, about 100000 to about 800000, about 300000 to about 500000, about 300000 to about 700000, about 300000 to about 800000, about 500000 to about 1000000, about 500000 to about 700000, about 500000 to about 800000, about 500000 to about 1000000, about 700000 to about 800000, or about 800000 to about 1000000. In some embodiments, the polyvinylidene fluoride has an average molecular weight of about 50000, about 100000, about 300000, about 500000, about 700000, about 800000, or about 1000000. In some embodiments, the polyvinylidene fluoride (PVDF) has an average molecular weight of at least about 100000. In some embodiments, the polyvinylidene fluoride (PVDF) has an average molecular weight of about 300000 to about 700000.

In some embodiments, the polyvinylidene fluoride (PVDF) comprises about 5% (w/w) to about 40% (w/w) of the composition. In some embodiments, the polyvinylidene fluoride (PVDF) is at least about 5% (w/w) of the composition. In some embodiments, the polyvinylidene fluoride (PVDF) is up to about 40% (w/w) of the composition. In some embodiments, the polyvinylidene fluoride (PVDF) comprises about 5% (w/w) to about 10% (w/w) of the composition, about 5% (w/w) to about 20% (w/w) of the composition, about 5% (w/w) to about 30% (w/w) of the composition, about 5% (w/w) to about 40% (w/w) of the composition, about 10% (w/w) to about 20% (w/w) of the composition, about 10% (w/w) to about 30% (w/w) of the composition, about 10% (w/w) to about 40% (w/w) of the composition, about 20% (w/w) to about 30% (w/w) of the composition, about 20% (w/w) to about 40% (w/w) of the composition, or about 30% (w/w) of the composition Percent (w/w) to about 40 percent (w/w). In some embodiments, the polyvinylidene fluoride (PVDF) comprises about 5% (w/w) of the composition, about 10% (w/w) of the composition, about 20% (w/w) of the composition, about 30% (w/w) of the composition, or about 40% (w/w) of the composition. In some embodiments, the polyvinylidene fluoride (PVDF) comprises about 10% to about 30% (w/w) of the composition.

In some embodiments, the polymer comprises poly (vinyl pyrrolidone) (PVP, molecular weight 8-2000kDa), triethyl phosphate (TEP), Ethylene Glycol (EG), perfluorosulfonic acid, or any combination thereof. In some embodiments, the polymer comprises from about 1% (w/w) to about 10% (w/w) of the composition. In some embodiments, the polymer is at least about 1% (w/w) of the composition. In some embodiments, the polymer is up to about 10% (w/w) of the composition. In some embodiments, the polymer comprises from about 1% (w/w) to about 3% (w/w) of the composition, from about 1% (w/w) to about 5% (w/w) of the composition, from about 1% (w/w) to about 8% (w/w) of the composition, from about 1% (w/w) to about 10% (w/w) of the composition, from about 3% (w/w) to about 5% (w/w) of the composition, from about 3% (w/w) to about 8% (w/w) of the composition, from about 3% (w/w) to about 10% (w/w) of the composition, from about 5% (w/w) to about 8% (w/w) of the composition, from about 5% (w/w) to about 10% (w/w) of the composition, or from about 8% (w/w) of the composition w) to about 10% (w/w). In some embodiments, the polymer comprises about 1% (w/w) of the composition, about 3% (w/w) of the composition, about 5% (w/w) of the composition, about 8% (w/w) of the composition), or about 10% (w/w) of the composition. In some embodiments, the polymer comprises from about 1% to about 8% (w/w) of the composition.

In some embodiments, the composition further comprises polyvinyl alcohol (PVA), glutaraldehyde, dichloromethane, Octadecyltrichlorosilane (ODS), hydrochloric acid (HCl), or any combination thereof.

In some embodiments, the composition further comprises Triethylamine (TEA), camphorsulfonic acid (CSA), dimethyl sulfoxide (DMSO), metaphenylene diamine (MPD), 2-ethyl-1, 3-hexanediol (EHD), sodium lauryl sulfate (SLES), or any combination thereof. In some embodiments, the composition comprises from about 1% (w/w) of the triethylamine to about 5% (w/w) of the triethylamine. In some embodiments, the composition comprises at least about 1% (w/w) of the triethylamine. In some embodiments, the composition comprises up to about 5% (w/w) of the triethylamine. In some embodiments, the composition comprises from about 1% (w/w) of the triethylamine to about 2% (w/w) of the triethylamine, from about 1% (w/w) of the triethylamine to about 3% (w/w) of the triethylamine, from about 1% (w/w) of the triethylamine to about 4% (w/w) of the triethylamine, from about 1% (w/w) of the triethylamine to about 5% (w/w) of the triethylamine, from about 2% (w/w) of the triethylamine to about 3% (w/w) of the triethylamine, from about 2% (w/w) of the triethylamine to about 4% (w/w) of the triethylamine, from about 2% (w/w) of the triethylamine to about 5% (w/w) of the triethylamine, from about 3% (w/w) of the triethylamine to about 4% (w/w) of the triethylamine, a composition comprising at least one of the triethylamine, and at least, About 3% (w/w) of the triethylamine to about 5% (w/w) of the triethylamine or about 4% (w/w) of the triethylamine to about 5% (w/w) of the triethylamine. In some embodiments, the composition comprises about 1% (w/w) of the triethylamine, about 2% (w/w) of the triethylamine, about 3% (w/w) of the triethylamine, about 4% (w/w) of the triethylamine, or about 5% (w/w) of the triethylamine.

In some embodiments, the composition comprises from about 1% (w/w) of the camphorsulfonic acid to about 7% (w/w) of the camphorsulfonic acid. In some embodiments, the composition comprises at least about 1% (w/w) of the camphorsulfonic acid. In some embodiments, the composition comprises up to about 7% (w/w) of the camphorsulfonic acid. In some embodiments, the composition comprises from about 1% (w/w) of the camphorsulfonic acid to about 3% (w/w) of the camphorsulfonic acid, from about 1% (w/w) of the camphorsulfonic acid to about 5% (w/w) of the camphorsulfonic acid, from about 1% (w/w) of the camphorsulfonic acid to about 7% (w/w) of the camphorsulfonic acid, from about 3% (w/w) of the camphorsulfonic acid to about 5% (w/w) of the camphorsulfonic acid, from about 3% (w/w) of the camphorsulfonic acid to about 7% (w/w) of the camphorsulfonic acid, or from about 5% (w/w) of the camphorsulfonic acid to about 7% (w/w) of the camphorsulfonic acid. In some embodiments, the composition comprises about 1% (w/w) of the camphorsulfonic acid, about 3% (w/w) of the camphorsulfonic acid, about 5% (w/w) of the camphorsulfonic acid, or about 7% (w/w) of the camphorsulfonic acid.

In some embodiments, the composition comprises from about 1% (w/w) of the dimethyl sulfoxide to about 3% (w/w) of the dimethyl sulfoxide. In some embodiments, the composition comprises at least about 1% (w/w) of the dimethyl sulfoxide. In some embodiments, the composition comprises up to about 3% (w/w) of the dimethyl sulfoxide. In some embodiments, the composition comprises from about 1% (w/w) of the dimethylsulfoxide to about 1.5% (w/w) of the dimethylsulfoxide, from about 1% (w/w) of the dimethylsulfoxide to about 2% (w/w) of the dimethylsulfoxide, from about 1% (w/w) of the dimethylsulfoxide to about 2.5% (w/w) of the dimethylsulfoxide, from about 1% (w/w) of the dimethylsulfoxide to about 3% (w/w) of the dimethylsulfoxide, from about 1.5% (w/w) of the dimethylsulfoxide to about 2% (w/w) of the dimethylsulfoxide, from about 1.5% (w/w) of the dimethylsulfoxide to about 2.5% (w/w) of the dimethylsulfoxide, from about 1.5% (w/w) of the dimethylsulfoxide to about 3% (w/w) of the dimethylsulfoxide, and, About 2% (w/w) of the dimethyl sulfoxide to about 2.5% (w/w) of the dimethyl sulfoxide, about 2% (w/w) of the dimethyl sulfoxide to about 3% (w/w) of the dimethyl sulfoxide, or about 2.5% (w/w) of the dimethyl sulfoxide to about 3% (w/w) of the dimethyl sulfoxide. In some embodiments, the composition comprises about 1% (w/w) of the dimethylsulfoxide, about 1.5% (w/w) of the dimethylsulfoxide, about 2% (w/w) of the dimethylsulfoxide, about 2.5% (w/w) of the dimethylsulfoxide, or about 3% (w/w) of the dimethylsulfoxide.

In some embodiments, the composition comprises from about 0.2% (w/w) to about 4% (w/w) of the m-phenylenediamine. In some embodiments, the composition comprises at least about 0.2% (w/w) of the m-phenylenediamine. In some embodiments, the composition comprises up to about 4% (w/w) of the m-phenylenediamine. In some embodiments, the composition comprises about 0.2% (w/w) to about 1% (w/w) of the m-phenylenediamine, about 0.2% (w/w) to about 2% (w/w) of the m-phenylenediamine, about 0.2% (w/w) to about 3% (w/w) of the m-phenylenediamine, about 0.2% (w/w) to about 4% (w/w) of the m-phenylenediamine, about 1% (w/w) to about 2% (w/w) of the m-phenylenediamine, about 1% (w/w) to about 3% (w/w) of the m-phenylenediamine, about 1% (w/w) to about 4% (w/w) of the m-phenylenediamine, About 2% (w/w) of the m-phenylenediamine to about 3% (w/w) of the m-phenylenediamine, about 2% (w/w) of the m-phenylenediamine to about 4% (w/w) of the m-phenylenediamine, or about 3% (w/w) of the m-phenylenediamine to about 4% (w/w) of the m-phenylenediamine. In some embodiments, the composition comprises about 0.2% (w/w) of the m-phenylenediamine, about 1% (w/w) of the m-phenylenediamine, about 2% (w/w) of the m-phenylenediamine, about 3% (w/w) of the m-phenylenediamine, or about 4% (w/w) of the m-phenylenediamine.

In some embodiments, the composition comprises from about 0.1% (w/w) of the 2-ethyl-1, 3-hexanediol to about 0.5% (w/w) of the 2-ethyl-1, 3-hexanediol. In some embodiments, the composition comprises at least about 0.1% (w/w) of the 2-ethyl-1, 3-hexanediol. In some embodiments, the composition comprises up to about 0.5% (w/w) of the 2-ethyl-1, 3-hexanediol. In some embodiments, the composition comprises from about 0.1% (w/w) of the 2-ethyl-1, 3-hexanediol to about 0.2% (w/w) of the 2-ethyl-1, 3-hexanediol, from about 0.1% (w/w) of the 2-ethyl-1, 3-hexanediol to about 0.3% (w/w) of the 2-ethyl-1, 3-hexanediol, from about 0.1% (w/w) of the 2-ethyl-1, 3-hexanediol to about 0.4% (w/w) of the 2-ethyl-1, 3-hexanediol, from about 0.1% (w/w) of the 2-ethyl-1, 3-hexanediol to about 0.5% (w/w) of the 2-ethyl-1, 3-hexanediol, about 0.2% (w/w) of the 2-ethyl-1, 3-hexanediol to about 0.3% (w/w) of the 2-ethyl-1, 3-hexanediol, about 0.2% (w/w) of the 2-ethyl-1, 3-hexanediol to about 0.4% (w/w) of the 2-ethyl-1, 3-hexanediol, about 0.2% (w/w) of the 2-ethyl-1, 3-hexanediol to about 0.5% (w/w) of the 2-ethyl-1, 3-hexanediol, about 0.3% (w/w) of the 2-ethyl-1, 3-hexanediol to about 0.4% (w/w) of the 2-ethyl-1, 3-hexanediol, From about 0.3% (w/w) of the 2-ethyl-1, 3-hexanediol to about 0.5% (w/w) of the 2-ethyl-1, 3-hexanediol or from about 0.4% (w/w) of the 2-ethyl-1, 3-hexanediol to about 0.5% (w/w) of the 2-ethyl-1, 3-hexanediol. In some embodiments, the composition comprises about 0.1% (w/w) of the 2-ethyl-1, 3-hexanediol, about 0.2% (w/w) of the 2-ethyl-1, 3-hexanediol, about 0.3% (w/w) of the 2-ethyl-1, 3-hexanediol, about 0.4% (w/w) of the 2-ethyl-1, 3-hexanediol, or about 0.5% (w/w) of the 2-ethyl-1, 3-hexanediol.

In some embodiments, the composition comprises from about 0.1% (w/w) of the sodium lauryl sulfate to about 0.5% (w/w) of the sodium lauryl sulfate. In some embodiments, the composition comprises at least about 0.1% (w/w) of the sodium lauryl sulfate. In some embodiments, the composition comprises up to about 0.5% (w/w) of the sodium lauryl sulfate. In some embodiments, the composition comprises from about 0.1% (w/w) of the sodium lauryl sulfate to about 0.2% (w/w) of the sodium lauryl sulfate, from about 0.1% (w/w) of the sodium lauryl sulfate to about 0.3% (w/w) of the sodium lauryl sulfate, from about 0.1% (w/w) of the sodium lauryl sulfate to about 0.4% (w/w) of the sodium lauryl sulfate, from about 0.1% (w/w) of the sodium lauryl sulfate to about 0.5% (w/w) of the sodium lauryl sulfate, from about 0.2% (w/w) of the sodium lauryl sulfate to about 0.3% (w/w) of the sodium lauryl sulfate, from about 0.2% (w/w) of the sodium lauryl sulfate to about 0.4% (w/w) of the sodium lauryl sulfate, and, From about 0.2% (w/w) of the sodium lauryl sulfate to about 0.5% (w/w) of the sodium lauryl sulfate, from about 0.3% (w/w) of the sodium lauryl sulfate to about 0.4% (w/w) of the sodium lauryl sulfate, from about 0.3% (w/w) of the sodium lauryl sulfate to about 0.5% (w/w) of the sodium lauryl sulfate, or from about 0.4% (w/w) of the sodium lauryl sulfate to about 0.5% (w/w) of the sodium lauryl sulfate. In some embodiments, the composition comprises about 0.1% (w/w) of the sodium lauryl sulfate, about 0.2% (w/w) of the sodium lauryl sulfate, about 0.3% (w/w) of the sodium lauryl sulfate, about 0.4% (w/w) of the sodium lauryl sulfate, or about 0.5% (w/w) of the sodium lauryl sulfate.

In some embodiments, the composition further comprises 1,3, 5-benzenetricarboxylic acid chloride (TMC), tributyl phosphate (TBP), or any combination thereof.

In some embodiments, the composition comprises from about 0.01% (w/w) of the 1,3, 5-benzenetricarboxylic acid chloride to about 0.1% (w/w) of the 1,3, 5-benzenetricarboxylic acid chloride. In some embodiments, the composition comprises at least about 0.01% (w/w) of said 1,3, 5-benzenetricarboxylic acid chloride. In some embodiments, the composition comprises up to about 0.1% (w/w) of the 1,3, 5-benzenetricarboxylic acid chloride. In some embodiments, the composition comprises from about 0.01% (w/w) of the 1,3, 5-benzenetricarboxylic acid chloride to about 0.05% (w/w) of the 1,3, 5-benzenetricarboxylic acid chloride, from about 0.01% (w/w) of the 1,3, 5-benzenetricarboxylic acid chloride to about 0.1% (w/w) of the 1,3, 5-benzenetricarboxylic acid chloride, or from about 0.05% (w/w) of the 1,3, 5-benzenetricarboxylic acid chloride to about 0.1% (w/w) of the 1,3, 5-benzenetricarboxylic acid chloride. In some embodiments, the composition comprises about 0.01% (w/w) of the 1,3, 5-benzenetricarboxylic acid chloride, about 0.05% (w/w) of the 1,3, 5-benzenetricarboxylic acid chloride, or about 0.1% (w/w) of the 1,3, 5-benzenetricarboxylic acid chloride.

In some embodiments, the composition comprises from about 0.1% (w/w) of the tributyl phosphate to about 0.5% (w/w) of the tributyl phosphate. In some embodiments, the composition comprises at least about 0.1% (w/w) of the tributyl phosphate. In some embodiments, the composition comprises up to about 0.5% (w/w) of the tributyl phosphate. In some embodiments, the composition comprises from about 0.1% (w/w) of the tributyl phosphate to about 0.2% (w/w) of the tributyl phosphate, from about 0.1% (w/w) of the tributyl phosphate to about 0.3% (w/w) of the tributyl phosphate, from about 0.1% (w/w) of the tributyl phosphate to about 0.4% (w/w) of the tributyl phosphate, from about 0.1% (w/w) of the tributyl phosphate to about 0.5% (w/w) of the tributyl phosphate, from about 0.2% (w/w) of the tributyl phosphate to about 0.3% (w/w) of the tributyl phosphate, from about 0.2% (w/w) of the tributyl phosphate to about 0.4% (w/w) of the tributyl phosphate, from about 0.2% (w/w) of the tributyl phosphate to about 0.5% (w/w) of the tributyl phosphate, From about 0.3% (w/w) of the tributyl phosphate to about 0.4% (w/w) of the tributyl phosphate, from about 0.3% (w/w) of the tributyl phosphate to about 0.5% (w/w) of the tributyl phosphate, or from about 0.4% (w/w) of the tributyl phosphate to about 0.5% (w/w) of the tributyl phosphate. In some embodiments, the composition comprises about 0.1% (w/w) of the tributyl phosphate, about 0.2% (w/w) of the tributyl phosphate, about 0.3% (w/w) of the tributyl phosphate, about 0.4% (w/w) of the tributyl phosphate, or about 0.5% (w/w) of the tributyl phosphate.

In some embodiments, the composition further comprises a carboxylic acid, oxalic acid, citric acid, phosphoric acid, benzoic acid, dihydroxybenzene, dopamine, or any combination thereof. In some embodiments, the composition further comprises Polyethersulfone (PES). In some embodiments, the polyethersulfone has an average molecular weight of about 10000 to about 80000. In some embodiments, the polyethersulfone has an average molecular weight of at least about 10000. In some embodiments, the polyethersulfone has an average molecular weight of at most about 80000. In some embodiments, the polyethersulfone has an average molecular weight of about 10000 to about 20000, about 10000 to about 30000, about 10000 to about 45000, about 10000 to about 55000, about 10000 to about 68000, about 10000 to about 80000, about 20000 to about 30000, about 20000 to about 45000, about 20000 to about 55000, about 20000 to about 68000, about 20000 to about 80000, about 30000 to about 45000, about 30000 to about 55000, about 30000 to about 68000, about 30000 to about 80000, about 45000 to about 55000, about 45000 to about 68000, about 45000 to about 80000, about 55000 to about 68000, about 55000 to about 80000, or about 68000 to about 80000. In some embodiments, the polyethersulfone has an average molecular weight of about 10000, about 20000, about 30000, about 45000, about 55000, about 68000, or about 80000.

In some embodiments, the polyethersulfone comprises between about 10% (w/w) and about 40% (w/w) of the composition. In some embodiments, the polyethersulfone comprises at least about 10% (w/w) of the composition. In some embodiments, the polyethersulfone comprises up to about 40% (w/w) of the composition. In some embodiments, the polyethersulfone comprises about 10% (w/w) to about 15% (w/w) of the composition, about 10% (w/w) to about 20% (w/w) of the composition, about 10% (w/w) to about 25% (w/w) of the composition, about 10% (w/w) to about 30% (w/w) of the composition, about 10% (w/w) to about 35% (w/w) of the composition, about 10% (w/w) to about 40% (w/w) of the composition, about 15% (w/w) to about 20% (w/w) of the composition, about 15% (w/w) to about 25% (w/w) of the composition, about 15% (w/w) to about 30% (w/w) of the composition, about 15% (w/w) to about 35% (w/w) of the composition, or a combination thereof, From about 15% (w/w) to about 40% (w/w) of the composition, from about 20% (w/w) to about 25% (w/w) of the composition, from about 20% (w/w) to about 30% (w/w) of the composition, from about 20% (w/w) to about 35% (w/w) of the composition, from about 20% (w/w) to about 40% (w/w) of the composition, from about 25% (w/w) to about 30% (w/w) of the composition, from about 25% (w/w) to about 35% (w/w) of the composition, from about 25% (w/w) to about 40% (w/w) of the composition, from about 30% (w/w) to about 35% (w/w) of the composition, from about 30% (w/w) to about 40% (w/w) of the composition, From about 35% (w/w) to about 40% (w/w) of the composition. In some embodiments, the polyethersulfone comprises about 10% (w/w) of the composition, about 15% (w/w) of the composition, about 20% (w/w) of the composition, about 25% (w/w) of the composition, about 30% (w/w) of the composition, about 35% (w/w) of the composition, or about 40% (w/w) of the composition.

In some embodiments, the composition further comprises a sugar. In some embodiments, the sugar comprises a monosaccharide, a disaccharide, a polysaccharide, or any combination thereof. In some embodiments, the sugar comprises glucose, fructose, sucrose, or any combination thereof.

In some embodiments, the composition comprises from about 1% (w/w) sugar to about 95% (w/w) sugar. In some embodiments, the composition comprises at least about 1% (w/w) of the sugar. In some embodiments, the composition comprises up to about 95% (w/w) of the sugar. In some embodiments, the composition comprises from about 1% (w/w) of the sugar to about 10% (w/w) of the sugar, from about 1% (w/w) of the sugar to about 20% (w/w) of the sugar, from about 1% (w/w) of the sugar to about 40% (w/w) of the sugar, from about 1% (w/w) of the sugar to about 60% (w/w) of the sugar, from about 1% (w/w) of the sugar to about 80% (w/w) of the sugar, from about 1% (w/w) of the sugar to about 95% (w/w) of the sugar, from about 10% (w/w) of the sugar to about 20% (w/w) of the sugar, from about 10% (w/w) of the sugar to about 40% (w/w) of the sugar, from about 10% (w/w) of the sugar to about 60% (w/w) of the sugar, and, About 10% (w/w) of the sugar to about 80% (w/w) of the sugar, about 10% (w/w) of the sugar to about 95% (w/w) of the sugar, about 20% (w/w) of the sugar to about 40% (w/w) of the sugar, about 20% (w/w) of the sugar to about 60% (w/w) of the sugar, about 20% (w/w) of the sugar to about 80% (w/w) of the sugar, about 20% (w/w) of the sugar to about 95% (w/w) of the sugar, about 40% (w/w) of the sugar to about 60% (w/w) of the sugar, about 40% (w/w) of the sugar to about 80% (w/w) of the sugar, about 40% (w/w) of the sugar to about 95% (w/w) of the sugar, and, About 60% (w/w) of the sugar to about 80% (w/w) of the sugar, about 60% (w/w) of the sugar to about 95% (w/w) of the sugar, or about 80% (w/w) of the sugar to about 95% (w/w) of the sugar. In some embodiments, the composition comprises about 1% (w/w) of the sugar, about 10% (w/w) of the sugar, about 20% (w/w) of the sugar, about 40% (w/w) of the sugar, about 60% (w/w) of the sugar, about 80% (w/w) of the sugar, or about 95% (w/w) of the sugar.

In another aspect, a film comprising any of the compositions disclosed herein is disclosed. In some embodiments, the membrane further comprises a support layer. In some embodiments, the support layer comprises a nonwoven fabric. In some embodiments, the nonwoven fabric comprises a polypropylene nonwoven fabric.

In some embodiments, the water contact angle of the membrane is at most about 10 °, about 20 °, about 30 °, about 40 °, about 50 °, about 60 °, about 70 °, about 80 °, or about 90 °. In some embodiments, the water contact angle is about 10 ° to about 90 °. In some embodiments, the water contact angle is from about 10 ° to about 20 °, from about 10 ° to about 30 °, from about 10 ° to about 40 °, from about 10 ° to about 50 °, from about 10 ° to about 60 °, from about 10 ° to about 70 °, from about 10 ° to about 80 °, from about 10 ° to about 90 °, from about 20 ° to about 30 °, from about 20 ° to about 40 °, from about 20 ° to about 50 °, from about 20 ° to about 60 °, from about 20 ° to about 70 °, from about 20 ° to about 80 °, from about 20 ° to about 90 °, from about 30 ° to about 40 °, from about 30 ° to about 50 °, from about 30 ° to about 60 °, from about 30 ° to about 70 °, from about 30 ° to about 80 °, from about 40 ° to about 60 °, from about 40 ° to about 70 °, from about 40 ° to about 80 °, from about 40 ° to about 90 °, from about 50 ° to about 60 °, from about 50 ° to about 70 °, from about 50 ° to about 80 °, from about 50 ° to about 90 °, from about 60 ° to about 70 ° About 60 ° to about 80 °, about 60 ° to about 90 °, about 70 ° to about 80 °, about 70 ° to about 90 °, or about 80 ° to about 90 °. In some embodiments, the water contact angle is about 10 °, about 20 °, about 30 °, about 40 °, about 50 °, about 60 °, about 70 °, about 80 °, or about 90 °. In some embodiments, the water contact angle is less than 80 °. In some embodiments, the water contact angle is about 40 ° to about 60 °.

In some embodiments, the membrane has an average surface pore size of about 1 nm to about 120 nm. In some embodiments, the membrane has an average surface pore size of at least about 1 nanometer. In some embodiments, the membrane has an average surface pore size of up to about 120 nanometers. In some embodiments, the membrane has an average surface pore size of about 1 nm to about 2 nm, about 1 nm to about 5 nm, about 1 nm to about 8 nm, about 1 nm to about 10 nm, about 1 nm to about 40 nm, about 1 nm to about 80 nm, about 1 nm to about 120 nm, about 2 nm to about 5 nm, about 2 nm to about 8 nm, about 2 nm to about 10 nm, about 2 nm to about 40 nm, about 2 nm to about 80 nm, about 2 nm to about 120 nm, about 5 nm to about 8 nm, about 5 nm to about 10 nm, about 5 nm to about 40 nm, about 5 nm to about 80 nm, about 5 nm to about 120 nm, about 8 nm to about 40 nm, about 8 nm to about 80 nm, about 8 nm to about 120 nm, about 10 nm to about 40 nm, about 10 nm to about 80 nm, From about 10 nanometers to about 120 nanometers, from about 40 nanometers to about 80 nanometers, from about 40 nanometers to about 120 nanometers, or from about 80 nanometers to about 120 nanometers. In some embodiments, the membrane has an average surface pore size of about 1 nanometer, about 2 nanometers, about 5 nanometers, about 8 nanometers, about 10 nanometers, about 40 nanometers, about 80 nanometers, or about 120 nanometers. In some embodiments, the membrane has an average surface pore size of at least 1 nanometer. In some embodiments, the average surface pore size is about 2 nanometers to about 8 nanometers. In some embodiments, the average surface pore size is about 10 nanometers to about 80 nanometers.

In some embodiments, the porosity of the membrane is about 50% to about 95%. In some embodiments, the porosity of the membrane is at least about 50%. In some embodiments, the porosity of the membrane is at most about 95%. In some embodiments, the porosity of the membrane is about 50% to about 60%, about 50% to about 70%, about 50% to about 80%, about 50% to about 85%, about 50% to about 90%, about 50% to about 95%, about 60% to about 70%, about 60% to about 80%, about 60% to about 85%, about 60% to about 90%, about 60% to about 95%, about 70% to about 80%, about 70% to about 85%, about 70% to about 90%, about 70% to about 95%, about 80% to about 85%, about 80% to about 90%, about 80% to about 95%, about 85% to about 90%, about 85% to about 95%, or about 90% to about 95%. In some embodiments, the membrane has a porosity of about 50%, about 60%, about 70%, about 80%, about 85%, about 90%, or about 95%. In some embodiments, the porosity of the membrane is at least 50%. In some embodiments, the porosity is about 70% to about 85%.

In some embodiments, the membrane has a water permeability of about 100LMH/bar to about 800 LMH/bar. In some embodiments, the membrane has a water permeability of at least about 100 LMH/bar. In some embodiments, the membrane has a water permeability of at most about 800 LMH/bar. In some embodiments, the membrane has a water permeability of about 100 to about 200LMH/bar, about 100 to about 300LMH/bar, about 100 to about 400LMH/bar, about 100 to about 500LMH/bar, about 100 to about 600LMH/bar, about 100 to about 700LMH/bar, about 100 to about 800LMH/bar, about 200 to about 300LMH/bar, about 200 to about 400LMH/bar, about 200 to about 500LMH/bar, about 200 to about 400LMH/bar, about 200 to about 500LMH/bar, about 200 to about 600LMH/bar, about 200 to about 700LMH/bar, about 200 to about 800LMH/bar, about 300 to about 400LMH/bar, about 300 to about 500LMH/bar, and about 500 to about 500LMH/bar, About 300 to about 600, about 300 to about 700, about 300 to about 800, about 400 to about 500, about 400 to about 600, about 400 to about 700, about 400 to about 800, about 500 to about 600, about 500 to about 700, about 500 to about 800, about 600 to about 700, about 500 to about 800, about 600 to about 800, or about 700 to about 800. In some embodiments, the membrane has a water permeability of about 100LMH/bar, about 200LMH/bar, about 300LMH/bar, about 400LMH/bar, about 500LMH/bar, about 600LMH/bar, about 700LMH/bar, or about 800 LMH/bar. In some embodiments, the membrane has a water permeability of at least 200 LMH/bar. In some embodiments, the water permeability is about 500LMH/bar to about 600 LMH/bar. In some embodiments, the membrane has a water permeability of at least 2LMH/bar at 15.5bar using 2000ppm sodium chloride solution.

In some embodiments, the membrane has a rejection rate of about 60% to about 99%. In some embodiments, the membrane has a salt rejection of at least about 60%. In some embodiments, the membrane has a rejection rate of at most about 99%. In some embodiments, the membrane has a salt rejection of about 60% to about 80%, about 60% to about 90%, about 60% to about 95%, about 60% to about 99%, about 80% to about 90%, about 80% to about 95%, about 80% to about 99%, about 90% to about 95%, about 90% to about 99%, or about 95% to about 99%. In some embodiments, the membrane has a salt rejection of about 60%, about 80%, about 90%, about 95%, or about 99%. In some embodiments, the membrane has a salt rejection of at least 80%.

In another aspect, a water permeable device is disclosed that includes any of the membranes disclosed in the present application.

In another aspect, a method is disclosed, comprising: mixing graphite powder with an oxidant to produce a composition comprising graphene oxide, wherein the graphene oxide has an average particle size of no more than about 1 micron and an atomic percent of oxygen of at least about 30%. In some embodiments, the graphene oxide has an average particle size of about 0.001 microns to about 2 microns. In some embodiments, the graphene oxide has an average particle size of at least about 0.001 microns. In some embodiments, the graphene oxide has an average particle size of at most about 2 microns. In some embodiments, the graphene oxide has an average particle size of at most about 1.5 microns. In some embodiments, the graphene oxide has an average particle size of at most about 1 micron. In some embodiments, the graphene oxide has an average particle size of at most about 0.5 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.2 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.1 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.05 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.01 microns. In some embodiments, the graphene oxide has an average particle size of about 2 microns to about 1.5 microns, about 2 microns to about 1 micron, about 2 microns to about 0.5 microns, about 2 microns to about 0.2 microns, about 2 microns to about 0.1 microns, about 2 microns to about 0.05 microns, about 2 microns to about 0.01 microns, about 2 microns to about 0.005 microns, about 2 microns to about 0.001 microns, about 1.5 microns to about 1 micron, about 1.5 microns to about 0.5 microns, about 1.5 microns to about 0.2 microns, about 1.5 microns to about 0.1 microns, about 1.5 microns to about 0.05 microns, about 1.5 microns to about 0.01 microns, about 1.5 microns to about 0.005 microns, about 1.5 microns to about 0.001 microns, about 1 microns to about 0.5 microns, about 1 microns to about 0.2 microns, about 1 microns to about 1.001 microns, about 1 microns to about 0.05 microns, about 1.0 microns to about 0.005 microns, about 1.05 microns, about 1 microns to about 0.001 microns, about 0.05 microns, about 1 micron to about 0.05 microns, about 1 micron to about 0.001 microns, about 0.05 microns, about 1 micron, About 0.5 microns to about 0.2 microns, about 0.5 microns to about 0.1 microns, about 0.5 microns to about 0.05 microns, about 0.5 microns to about 0.01 microns, about 0.5 microns to about 0.005 microns, about 0.5 microns to about 0.001 microns, about 0.2 microns to about 0.1 microns, about 0.2 microns to about 0.05 microns, about 0.2 microns to about 0.01 microns, about 0.2 microns to about 0.005 microns, about 0.2 microns to about 0.001 microns, about 0.1 microns to about 0.05 microns, about 0.1 microns to about 0.01 microns, about 0.1 microns to about 0.005 microns, about 0.1 microns to about 0.001 microns, about 0.05 microns to about 0.01 microns, about 0.05 microns to about 0.005 microns, about 0.05 microns to about 0.001 microns, about 0.001 microns to about 0.01 microns, about 0.001 microns to about 0.005 microns, or about 0.5 microns to about 0.001 microns. In some embodiments, the graphene oxide has an average particle size of about 2 microns, about 1.5 microns, about 1 micron, about 0.5 microns, about 0.2 microns, about 0.1 microns, about 0.05 microns, about 0.01 microns, about 0.005 microns, or about 0.001 microns. In some embodiments, the composition comprising graphene oxide is any of the compositions disclosed in this application.

In some embodiments, the method further comprises milling a graphite-containing composition to produce the graphite powder, wherein the graphite powder has an average particle size of no more than about 2 microns. In some embodiments, the graphite powder has an average particle size of about 0.5 microns to about 3 microns. In some embodiments, the graphite powder has an average particle size of at least about 0.5 microns. In some embodiments, the graphite powder has an average particle size of at most about 3 microns. In some embodiments, the graphite powder has an average particle size of about 0.5 microns to about 1 micron, about 0.5 microns to about 1.5 microns, about 0.5 microns to about 2 microns, about 0.5 microns to about 2.5 microns, about 0.5 microns to about 3 microns, about 1 micron to about 1.5 microns, about 1 micron to about 2 microns, about 1 micron to about 2.5 microns, about 1 micron to about 3 microns, about 1.5 microns to about 2 microns, about 1.5 microns to about 2.5 microns, about 1.5 microns to about 3 microns, about 2 microns to about 2.5 microns, about 2 microns to about 3 microns, or about 2.5 microns to about 3 microns. In some embodiments, the graphite powder has an average particle size of about 0.5 microns, about 1 micron, about 1.5 microns, about 2 microns, about 2.5 microns, or about 3 microns.

In some embodiments, the oxidant comprises oxygen (O)₂) Ozone (O)₃) Hydrogen peroxide (H)₂O₂) Fenton's reagent, fluorine (F)₂) Chlorine (Cl)₂) Bromine (Br)₂) Iodine (I)₂) Nitric acid (HNO)₃) Sulfuric acid (H)₂SO₄) Peroxodisulfuric acid (H)₂S₂O₈) Peroxomonosulfuric acid (H)₂SO₅) Chlorite, chlorate, perchlorate, hypochlorite, bleach (NaClO), chromic acid, dichromic acid, chromium trioxide, pyridinium chlorochromate (PCC), potassium permanganate, sodium perborate, nitrous oxide (N)₂O), nitrogen dioxide (NO)₂) Dinitrogen tetroxide (N)₂O₄) Potassium nitrate (KNO)₃) Sodium bismuthate or any combination thereof. In some embodiments, the oxidizing agent comprises sulfuric acid, potassium permanganate, hydrogen peroxide, or any combination thereof.

In some embodiments, the method further comprises mixing the composition comprising graphene oxide with an organic solvent to form a mixture. In some embodiments, the organic solvent comprises a non-polar solvent, a polar aprotic solvent, a polar protic solvent, or any combination thereof. In some embodiments, the non-polar solvent comprises pentane, cyclopentane, hexane, cyclohexane, benzene, toluene, 1, 4-dioxane, chloroform, diethyl ether, Dichloromethane (DCM), or any combination thereof. In some embodiments, the polar aprotic solvent comprises Tetrahydrofuran (THF), ethyl acetate, acetone, Dimethylformamide (DMF), acetonitrile (MeCN), dimethyl sulfoxide (DMSO), nitromethane, propylene carbonate, or any combination thereof. In some embodiments, the polar protic solvent comprises formic acid, n-butanol, Isopropanol (IPA), n-propanol, ethanol, methanol, acetic acid, or any combination thereof.

In some embodiments, the method further comprises separating a solid comprising graphene oxide from the mixture. In some embodiments, the separating comprises fractionating, centrifuging, filtering, or any combination thereof. In some embodiments, the filtration uses a pressure filter or electrodialysis.

In some embodiments, the method further comprises washing the solid comprising graphene oxide with a second organic solvent. In some embodiments, the second organic solvent comprises ethanol, methanol, or any combination thereof.

In some embodiments, the method further comprises drying the solid comprising graphene oxide.

In another aspect, a method is disclosed, comprising: a) heating the sugar solution to produce a solid powder; b) mixing the solid powder with an oxidizing agent to produce a composition comprising graphene oxide, wherein the graphene oxide has an average particle size of no more than about 1 micron and an atomic percent of oxygen of at least about 30%. In some embodiments, the graphene oxide has an average particle size of about 0.001 microns to about 2 microns. In some embodiments, the graphene oxide has an average particle size of at least about 0.001 microns. In some embodiments, the graphene oxide has an average particle size of at most about 2 microns. In some embodiments, the graphene oxide has an average particle size of at most about 1.5 microns. In some embodiments, the graphene oxide has an average particle size of at most about 1 micron. In some embodiments, the graphene oxide has an average particle size of at most about 0.5 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.2 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.1 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.05 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.01 microns. In some embodiments, the graphene oxide has an average particle size of from about 2 microns to about 1.5 microns, from about 2 microns to about 1 micron, from about 2 microns to about 0.5 microns, from about 2 microns to about 0.2 microns, from about 2 microns to about 0.1 microns, from about 2 microns to about 0.05 microns, from about 2 microns to about 0.01 microns, from about 2 microns to about 0.005 microns, from about 2 microns to about 0.001 microns, from about 1.5 microns to about 1 micron, from about 1.5 microns to about 0.5 microns, from about 1.5 microns to about 0.2 microns, from about 1.5 microns to about 0.1 microns, from about 1.5 microns to about 0.05 microns, from about 1.5 microns to about 0.01 microns, from about 1.5 microns to about 0.005 microns, from about 1.5 microns to about 0.001 microns, from about 1 microns to about 0.5 microns, from about 1 microns to about 0.2 microns, from about 1 micron to about 1.001 microns, from about 0.05 microns, from about 1 microns to about 0.005 microns, from about 0.05 microns, from about 1.0 microns to about 0.05 microns, from about 1.0 microns to about 0.001 microns, from about 0.05 microns, from about 1.05, About 0.5 microns to about 0.2 microns, about 0.5 microns to about 0.1 microns, about 0.5 microns to about 0.05 microns, about 0.5 microns to about 0.01 microns, about 0.5 microns to about 0.005 microns, about 0.5 microns to about 0.001 microns, about 0.2 microns to about 0.1 microns, about 0.2 microns to about 0.05 microns, about 0.2 microns to about 0.01 microns, about 0.2 microns to about 0.005 microns, about 0.2 microns to about 0.001 microns, about 0.1 microns to about 0.05 microns, about 0.1 microns to about 0.01 microns, about 0.1 microns to about 0.005 microns, about 0.1 microns to about 0.001 microns, about 0.05 microns to about 0.01 microns, about 0.05 microns to about 0.005 microns, about 0.05 microns to about 0.001 microns, about 0.001 microns to about 0.01 microns, about 0.001 microns to about 0.005 microns, or about 0.5 microns to about 0.001 microns. In some embodiments, the graphene oxide has an average particle size of about 2 microns, about 1.5 microns, about 1 micron, about 0.5 microns, about 0.2 microns, about 0.1 microns, about 0.05 microns, about 0.01 microns, about 0.005 microns, or about 0.001 microns. In some embodiments, the composition comprising graphene oxide is any composition disclosed herein.

In some embodiments, the composition further comprises a sugar. In some embodiments, the sugar comprises a monosaccharide, a disaccharide, a polysaccharide, or any combination thereof. In some embodiments, the sugar comprises glucose, fructose, sucrose, or any combination thereof. In some embodiments, the composition comprises about 1% to about 60% (w/w) of the sugar.

In some embodiments, the method further comprises heating the sugar solution to about 100 ℃ to about 250 ℃. In some embodiments, the method further comprises heating the sugar solution to at least about 100 ℃. In some embodiments, the method further comprises heating the sugar solution to at most about 250 ℃. In some embodiments, the process further comprises heating the sugar solution to about 100 ℃ to about 150 ℃, about 100 ℃ to about 180 ℃, about 100 ℃ to about 220 ℃, about 100 ℃ to about 250 ℃, about 150 ℃ to about 180 ℃, about 150 ℃ to about 220 ℃, about 150 ℃ to about 250 ℃, about 180 ℃ to about 220 ℃, about 180 ℃ to about 250 ℃, or about 220 ℃ to about 250 ℃. In some embodiments, the method further comprises heating the sugar solution to about 100 ℃, about 150 ℃, about 180 ℃, about 220 ℃, or about 250 ℃. In some embodiments, the method further comprises heating the sugar solution to at least 100 ℃. In some embodiments, the method further comprises heating the sugar solution to 180-.

In some embodiments, the method further comprises heating the sugar solution at a pressure of about 2atm to about 20 atm. In some embodiments, the method further comprises heating the sugar solution at a pressure of at least about 2 atm. In some embodiments, the method further comprises heating the sugar solution at a pressure of up to about 20 atm. In some embodiments, the process further comprises heating the sugar solution to about 2atm to about 6atm, about 2atm to about 10atm, about 2atm to about 12atm, about 2atm to about 15atm, about 2atm to about 20atm, about 6atm to about 10atm, about 6atm to about 12atm, about 6atm to about 15atm, about 6atm to about 20atm, about 10atm to about 12atm, about 10atm to about 15atm, about 10atm to about 20atm, about 12atm to about 15atm, about 12atm to about 20atm, or about 15atm to about 20 atm. In some embodiments, the method further comprises heating the sugar solution at about 2atm, about 6atm, about 10atm, about 12atm, about 15atm, or about 20 atm. In some embodiments, the method further comprises heating the sugar solution at a pressure greater than 2 atm. In some embodiments, the method further comprises heating the sugar solution at a pressure of 12-20 atm.

In some embodiments, the oxidant comprises oxygen (O)₂) Ozone (O)₃) Hydrogen peroxide (H)₂O₂) Fenton's reagent, fluorine (F)₂) Chlorine (Cl)₂) Bromine (Br)₂) Iodine (I)₂) Nitric acid (HNO)₃) Sulfuric acid (H)₂SO₄) Peroxodisulfuric acid (H)₂S₂O₈) Peroxomonosulfuric acid (H)₂SO₅) Chlorite, chlorate, perchlorate, hypochlorite, bleach (NaClO), chromic acid, dichromic acid, chromium trioxide, pyridinium chlorochromate (PCC), potassium permanganate, sodium perborate, nitrous oxide (N)₂O), nitrogen dioxide (NO)₂) Dinitrogen tetroxide (N)₂O₄) Potassium nitrate (KNO)₃) Sodium bismuthate or any combination thereof. In some embodiments, the oxidizing agent comprises sulfuric acid, potassium permanganate, hydrogen peroxide, or any combination thereof.

In some embodiments, the method further comprises separating a solid comprising graphene oxide from the oxidant. In some embodiments, the separating comprises fractionating, centrifuging, filtering, or any combination thereof. In some embodiments, the filtration uses a pressure filter or electrodialysis.

In some embodiments, the method further comprises washing the solid comprising graphene oxide with a second organic solvent. In some embodiments, the second organic solvent comprises ethanol, methanol, or any combination thereof.

In some embodiments, the method further comprises drying the solid comprising graphene oxide.

In another aspect, a method is disclosed, comprising: a) mixing a sugar component with an acidic component; b) heating the sugar component to produce a composition comprising graphene oxide, wherein the graphene oxide has an average particle size of no more than about 1 micron and an atomic percent of oxygen of at least about 30%. In some embodiments, the graphene oxide has an average particle size of about 0.001 microns to about 2 microns. In some embodiments, the graphene oxide has an average particle size of at least about 0.001 microns. In some embodiments, the graphene oxide has an average particle size of at most about 2 microns. In some embodiments, the graphene oxide has an average particle size of at most about 1.5 microns. In some embodiments, the graphene oxide has an average particle size of at most about 1 micron. In some embodiments, the graphene oxide has an average particle size of at most about 0.5 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.2 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.1 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.05 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.01 microns. In some embodiments, the graphene oxide has an average particle size of from about 2 microns to about 1.5 microns, from about 2 microns to about 1 micron, from about 2 microns to about 0.5 microns, from about 2 microns to about 0.2 microns, from about 2 microns to about 0.1 microns, from about 2 microns to about 0.05 microns, from about 2 microns to about 0.01 microns, from about 2 microns to about 0.005 microns, from about 2 microns to about 0.001 microns, from about 1.5 microns to about 1 micron, from about 1.5 microns to about 0.5 microns, from about 1.5 microns to about 0.2 microns, from about 1.5 microns to about 0.1 microns, from about 1.5 microns to about 0.05 microns, from about 1.5 microns to about 0.01 microns, from about 1.5 microns to about 0.005 microns, from about 1.5 microns to about 0.001 microns, from about 1 microns to about 0.5 microns, from about 1 microns to about 0.2 microns, from about 1 micron to about 1.001 microns, from about 0.05 microns, from about 1 microns to about 0.005 microns, from about 0.05 microns, from about 1.0 microns to about 0.05 microns, from about 1.0 microns to about 0.001 microns, from about 0.05 microns, from about 1.05, About 0.5 microns to about 0.2 microns, about 0.5 microns to about 0.1 microns, about 0.5 microns to about 0.05 microns, about 0.5 microns to about 0.01 microns, about 0.5 microns to about 0.005 microns, about 0.5 microns to about 0.001 microns, about 0.2 microns to about 0.1 microns, about 0.2 microns to about 0.05 microns, about 0.2 microns to about 0.01 microns, about 0.2 microns to about 0.005 microns, about 0.2 microns to about 0.001 microns, about 0.1 microns to about 0.05 microns, about 0.1 microns to about 0.01 microns, about 0.1 microns to about 0.005 microns, about 0.1 microns to about 0.001 microns, about 0.05 microns to about 0.01 microns, about 0.05 microns to about 0.005 microns, about 0.05 microns to about 0.001 microns, about 0.001 microns to about 0.01 microns, about 0.001 microns to about 0.005 microns, or about 0.5 microns to about 0.001 microns. In some embodiments, the graphene oxide has an average particle size of about 2 microns, about 1.5 microns, about 1 micron, about 0.5 microns, about 0.2 microns, about 0.1 microns, about 0.05 microns, about 0.01 microns, about 0.005 microns, or about 0.001 microns. In some embodiments, the composition comprising graphene oxide is any composition disclosed herein.

In some embodiments, the acidic component comprises carboxylic acid, oxalic acid, citric acid, phosphoric acid, benzoic acid, dihydroxybenzene, dopamine, or any combination thereof.

In some embodiments, the sugar comprises from about 1% to about 60% (w/w) of the composition comprising graphene oxide. In some embodiments, the sugar comprises a monosaccharide, a disaccharide, a polysaccharide, or any combination thereof. In some embodiments, the sugar comprises glucose, fructose, sucrose, or any combination thereof.

In some embodiments, the method further comprises heating the sugar solution to about 100 ℃ to about 250 ℃. In some embodiments, the method further comprises heating the sugar solution to at least about 100 ℃. In some embodiments, the method further comprises heating the sugar solution to at most about 250 ℃. In some embodiments, the process further comprises heating the sugar solution to about 100 ℃ to about 150 ℃, about 100 ℃ to about 180 ℃, about 100 ℃ to about 220 ℃, about 100 ℃ to about 250 ℃, about 150 ℃ to about 180 ℃, about 150 ℃ to about 220 ℃, about 150 ℃ to about 250 ℃, about 180 ℃ to about 220 ℃, about 180 ℃ to about 250 ℃, or about 220 ℃ to about 250 ℃. In some embodiments, the method further comprises heating the sugar solution to about 100 ℃, about 150 ℃, about 180 ℃, about 220 ℃, or about 250 ℃. In some embodiments, the method further comprises heating the sugar solution to at least 100 ℃. In some embodiments, the method further comprises heating the sugar solution to 180-.

In some embodiments, the method further comprises heating the sugar solution to about 2atm to about 20 atm. In some embodiments, the method further comprises heating the sugar solution at a pressure of at least about 2 atm. In some embodiments, the method further comprises heating the sugar solution at a pressure of up to about 20 atm. In some embodiments, the process further comprises heating the sugar solution to about 2atm to about 6atm, about 2atm to about 10atm, about 2atm to about 12atm, about 2atm to about 15atm, about 2atm to about 20atm, about 6atm to about 10atm, about 6atm to about 12atm, about 6atm to about 15atm, about 6atm to about 20atm, about 10atm to about 12atm, about 10atm to about 15atm, about 10atm to about 20atm, about 12atm to about 15atm, about 12atm to about 20atm, or about 15atm to about 20 atm. In some embodiments, the method further comprises heating the sugar solution at about 2atm, about 6atm, about 10atm, about 12atm, about 15atm, or about 20 atm. In some embodiments, the method further comprises heating the sugar solution at a pressure greater than 2 atm. In some embodiments, the method further comprises heating the sugar solution at a pressure of 12-20 atm.

In some embodiments, the method further comprises separating the solid comprising graphene oxide from the acidic component. In some embodiments, the separating comprises fractionating, centrifuging, filtering, or any combination thereof. In some embodiments, the filtration uses a pressure filter or electrodialysis.

In some embodiments, the method further comprises washing the solid comprising graphene oxide with a second organic solvent. In some embodiments, the second organic solvent comprises ethanol, methanol, or any combination thereof.

In some embodiments, the method further comprises drying the solid comprising graphene oxide.

In another aspect, a method is disclosed, comprising: a) mixing graphite powder with a first oxidant to produce a first composition comprising graphene oxide; b) mixing the first composition comprising graphene oxide with a second oxidant to produce a second composition comprising graphene oxide, wherein the graphene oxide has an average particle size of no more than about 1 micron and an atomic percent of oxygen of at least about 30%. In some embodiments, the graphene oxide has an average particle size of about 0.001 microns to about 2 microns. In some embodiments, the graphene oxide has an average particle size of at least about 0.001 microns. In some embodiments, the graphene oxide has an average particle size of at most about 2 microns. In some embodiments, the graphene oxide has an average particle size of at most about 1.5 microns. In some embodiments, the graphene oxide has an average particle size of at most about 1 micron. In some embodiments, the graphene oxide has an average particle size of at most about 0.5 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.2 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.1 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.05 microns. In some embodiments, the graphene oxide has an average particle size of at most about 0.01 microns. In some embodiments, the graphene oxide has an average particle size of from about 2 microns to about 1.5 microns, from about 2 microns to about 1 micron, from about 2 microns to about 0.5 microns, from about 2 microns to about 0.2 microns, from about 2 microns to about 0.1 microns, from about 2 microns to about 0.05 microns, from about 2 microns to about 0.01 microns, from about 2 microns to about 0.005 microns, from about 2 microns to about 0.001 microns, from about 1.5 microns to about 1 micron, from about 1.5 microns to about 0.5 microns, from about 1.5 microns to about 0.2 microns, from about 1.5 microns to about 0.1 microns, from about 1.5 microns to about 0.05 microns, from about 1.5 microns to about 0.01 microns, from about 1.5 microns to about 0.005 microns, from about 1.5 microns to about 0.001 microns, from about 1 microns to about 0.5 microns, from about 1 microns to about 0.2 microns, from about 1 micron to about 1.001 microns, from about 0.05 microns, from about 1 microns to about 0.005 microns, from about 0.05 microns, from about 1.0 microns to about 0.05 microns, from about 1.0 microns to about 0.001 microns, from about 0.05 microns, from about 1.05, About 0.5 microns to about 0.2 microns, about 0.5 microns to about 0.1 microns, about 0.5 microns to about 0.05 microns, about 0.5 microns to about 0.01 microns, about 0.5 microns to about 0.005 microns, about 0.5 microns to about 0.001 microns, about 0.2 microns to about 0.1 microns, about 0.2 microns to about 0.05 microns, about 0.2 microns to about 0.01 microns, about 0.2 microns to about 0.005 microns, about 0.2 microns to about 0.001 microns, about 0.1 microns to about 0.05 microns, about 0.1 microns to about 0.01 microns, about 0.1 microns to about 0.005 microns, about 0.1 microns to about 0.001 microns, about 0.05 microns to about 0.01 microns, about 0.05 microns to about 0.005 microns, about 0.05 microns to about 0.001 microns, about 0.001 microns to about 0.01 microns, about 0.001 microns to about 0.005 microns, or about 0.5 microns to about 0.001 microns. In some embodiments, the graphene oxide has an average particle size of about 2 microns, about 1.5 microns, about 1 micron, about 0.5 microns, about 0.2 microns, about 0.1 microns, about 0.05 microns, about 0.01 microns, about 0.005 microns, or about 0.001 microns. In some embodiments, the composition comprising graphene oxide is any composition disclosed herein.

In some embodiments, the first oxidant comprises oxygen (O)₂) Ozone (O)₃) Hydrogen peroxide (H)₂O₂) Fenton's reagent, fluorine (F)₂) Chlorine (Cl)₂) Bromine (Br)₂) Iodine (I)₂) Nitric acid (HNO)₃) Sulfuric acid (H)₂SO₄) Peroxodisulfuric acid (H)₂S₂O₈) Peroxomonosulfuric acid (H)₂SO₅) Chlorite, chlorate, perchlorate, hypochlorite, bleach (NaClO), chromic acid, dichromic acid, chromium trioxide, pyridinium chlorochromate (PCC), potassium permanganate, sodium perborate, nitrous oxide (N)₂O), nitrogen dioxide (NO)₂) Dinitrogen tetroxide (N)₂O₄) Potassium nitrate (KNO)₃) Sodium bismuthate or any combination thereof. In some embodiments, the first oxidizing agent comprises sulfuric acid, potassium permanganate, hydrogen peroxideOr any combination thereof.

In some embodiments, the method further comprises separating a first composition comprising graphene oxide from the first oxidizing agent. In some embodiments, the separating comprises fractionating, centrifuging, filtering, or any combination thereof. In some embodiments, the filtration uses a pressure filter or electrodialysis. In some embodiments, the second oxidizing agent comprises sulfuric acid, potassium permanganate, hydrogen peroxide, or any combination thereof.

In some embodiments, the method further comprises separating the second composition comprising graphene oxide from the second oxidant.

In some embodiments, the method further comprises washing the second composition comprising graphene oxide with a second organic solvent. In some embodiments, the second organic solvent comprises ethanol, methanol, or any combination thereof.

In some embodiments, the method further comprises drying the second composition comprising graphene oxide.

In another aspect, a method of making a membrane is disclosed, comprising: mixing the composition described in any of the preceding embodiments with an organic solvent. In some embodiments, the organic solvent comprises N, N-Dimethylacetamide (DMAC), N-methyl-2-pyrrolidone (nano-P), Dimethylformamide (DMF), or any combination thereof. In some embodiments, the organic solvent comprises an alkane and/or a cycloalkanone. In some embodiments, the cycloalkanone comprises hexane, isoparaffin, light alkylated naphtha, cyclohexanone, or any combination thereof.

In some embodiments, the method further comprises mixing the composition with an inorganic solvent. In some embodiments, the method further comprises dispersing the composition in the organic solvent using a high pressure homogenizer to produce an organic solution comprising graphene oxide.

In some embodiments, the method further comprises dispersing the composition in the inorganic solvent using a high pressure homogenizer to produce an inorganic solution comprising graphene oxide. In some embodiments, the dispersing is performed at about 5000psi to about 30000 psi. In some embodiments, the dispersing is performed at a pressure of at least about 5000 psi. In some embodiments, the dispersing is performed at a pressure of up to about 30000 psi. In some embodiments, the dispersing is performed at about 5000psi to about 10000psi, about 5000psi to about 15000psi, about 5000psi to about 20000psi, about 5000psi to about 25000psi, about 5000psi to about 30000psi, about 5000psi, 10000psi to about 15000psi, about 10000psi to about 20000psi, about 10000psi to about 25000psi, about 10000psi to about 30000psi, about 15000psi to about 20000psi, about 15000psi to about 25000psi, about 15000psi to about 30000psi, about 20000psi to about 25000psi, about 20000psi to about 30000psi, or about 25000psi to about 30000 psi. In some embodiments, the dispersing is performed at about 5000psi, about 10000psi, about 15000psi, about 20000psi, about 25000psi, or about 30000 psi. In some embodiments, the dispersing is performed at a pressure greater than 10000 psi. In some embodiments, the dispersing is performed at 15000-.

In some embodiments, the dispersing is performed from about 2 times to about 5 times. In some embodiments, the dispersing is performed at least about 2 times. In some embodiments, the dispersing is performed up to about 5 times. In some embodiments, the dispersing is performed from about 2 to about 3 times, from about 2 to about 4 times, from about 2 to about 5 times, from about 3 to about 4 times, from about 3 to about 5 times, or from about 4 to about 5 times. In some embodiments, the dispersing is performed about 2 times, about 3 times, about 4 times, or about 5 times.

In some embodiments, the method further comprises mixing the organic solution comprising graphene oxide with a polymer to form a polymer solution. In some embodiments, the polymer comprises polyvinylidene fluoride (PVDF). In some embodiments, the polyvinylidene fluoride has an average molecular weight of about 50000 to about 1000000. In some embodiments, the polyvinylidene fluoride has an average molecular weight of at least about 50000. In some embodiments, the polyvinylidene fluoride has an average molecular weight of up to about 1000000. In some embodiments, the polyvinylidene fluoride has an average molecular weight of about 50000 to about 100000, about 50000 to about 300000, about 50000 to about 500000, about 50000 to about 700000, about 50000 to about 800000, about 50000 to about 1000000, about 100000 to about 300000, about 100000 to about 500000, about 100000 to about 700000, about 100000 to about 800000, about 300000 to about 500000, about 300000 to about 700000, about 300000 to about 800000, about 500000 to about 1000000, about 500000 to about 700000, about 500000 to about 800000, about 500000 to about 1000000, about 700000 to about 800000, or about 800000 to about 1000000. In some embodiments, the polyvinylidene fluoride has an average molecular weight of about 50000, about 100000, about 300000, about 500000, about 700000, about 800000, or about 1000000. In some embodiments, the polyvinylidene fluoride (PVDF) has an average molecular weight of at least about 100000. In some embodiments, the average molecular weight is about 300000 to about 700000.

In some embodiments, the polyvinylidene fluoride (PVDF) is about 5% (w/w) to about 40% (w/w) of the composition. In some embodiments, the polyvinylidene fluoride (PVDF) is at least about 5% (w/w) of the composition. In some embodiments, the polyvinylidene fluoride (PVDF) is up to about 40% (w/w) of the composition. In some embodiments, the polyvinylidene fluoride (PVDF) is about 5% (w/w) to about 10% (w/w) of the composition, about 5% (w/w) to about 20% (w/w) of the composition, about 5% (w/w) to about 30% (w/w) of the composition, about 5% (w/w) to about 40% (w/w) of the composition, about 10% (w/w) to about 20% (w/w) of the composition, about 10% (w/w) to about 30% (w/w) of the composition, about 10% (w/w) to about 40% (w/w) of the composition, about 20% (w/w) to about 30% (w/w) of the composition, or a mixture thereof, From about 20% (w/w) of the composition to about 40% (w/w) of the composition or from about 30% (w/w) of the composition to about 40% (w/w) of the composition. In some embodiments, the polyvinylidene fluoride (PVDF) is about 5% (w/w) of the composition, about 10% (w/w) of the composition, about 20% (w/w) of the composition, about 30% (w/w) of the composition, or about 40% (w/w) of the composition. In some embodiments, the polyvinylidene fluoride (PVDF) is about 10% to about 30% (w/w) of the composition.

In some embodiments, the polymer comprises Polyethersulfone (PES). In some embodiments, the polyethersulfone has an average molecular weight of about 10000 to about 80000. In some embodiments, the polyethersulfone has an average molecular weight of at least about 10000. In some embodiments, the polyethersulfone has an average molecular weight of at most about 80000. In some embodiments, the polyethersulfone has an average molecular weight of about 10000 to about 20000, about 10000 to about 30000, about 10000 to about 45000, about 10000 to about 55000, about 10000 to about 68000, about 10000 to about 80000, about 20000 to about 30000, about 20000 to about 45000, about 20000 to about 55000, about 20000 to about 68000, about 20000 to about 80000, about 30000 to about 45000, about 30000 to about 55000, about 30000 to about 68000, about 30000 to about 80000, about 45000 to about 55000, about 45000 to about 68000, about 45000 to about 80000, about 55000 to about 68000, about 55000 to about 80000, or about 68000 to about 80000. In some embodiments, the polyethersulfone has an average molecular weight of about 10000, about 20000, about 30000, about 45000, about 55000, about 68000, or about 80000.

In some embodiments, the polyethersulfone is about 10% (w/w) to about 40% (w/w) of the composition. In some embodiments, the polyethersulfone is at least about 10% (w/w) of the composition. In some embodiments, the polyethersulfone is at most about 40% (w/w) of the composition. In some embodiments, the polyethersulfone is between about 10% (w/w) of the composition to about 15% (w/w) of the composition, between about 10% (w/w) of the composition to about 20% (w/w) of the composition, between about 10% (w/w) of the composition to about 25% (w/w) of the composition, between about 10% (w/w) of the composition to about 30% (w/w) of the composition, between about 10% (w/w) of the composition to about 35% (w/w) of the composition, between about 10% (w/w) of the composition to about 40% (w/w) of the composition, between about 15% (w/w) of the composition to about 20% (w/w) of the composition, between about 15% (w/w) of the composition to about 25% (w/w) of the composition, From about 15% (w/w) of the composition to about 30% (w/w) of the composition, from about 15% (w/w) of the composition to about 35% (w/w) of the composition, from about 15% (w/w) of the composition to about 40% (w/w) of the composition, from about 20% (w/w) of the composition to about 25% (w/w) of the composition, from about 20% (w/w) of the composition to about 30% (w/w) of the composition, from about 20% (w/w) of the composition to about 35% (w/w) of the composition, from about 20% (w/w) of the composition to about 40% (w/w) of the composition, from about 25% (w/w) of the composition to about 30% (w/w) of the composition, from about 25% (w/w) of the composition to about 35% (w/w) of the composition, from about 25% (w/w) of the composition to about 40% (w/w) of the composition, from about 30% (w/w) of the composition to about 35% (w/w) of the composition, from about 30% (w/w) of the composition to about 40% (w/w) of the composition, or from about 35% (w/w) of the composition to about 35% (w/w) of the composition. In some embodiments, the polyethersulfone is about 10% (w/w) of the composition, about 15% (w/w) of the composition, about 20% (w/w) of the composition, about 25% (w/w) of the composition, about 30% (w/w) of the composition, about 35% (w/w) of the composition, or about 40% (w/w) of the composition.

In some embodiments, the polymer comprises poly (vinyl pyrrolidone) (PVP molecular weight 8-2000kDa), triethyl phosphate (TEP), Ethylene Glycol (EG), perfluorosulfonic acid, or any combination thereof. In some embodiments, the polymer comprises from about 1% (w/w) to about 10% (w/w) of the composition. In some embodiments, the polymer is at least about 1% (w/w) of the composition. In some embodiments, the polymer is up to about 10% (w/w) of the composition. In some embodiments, the polymer is from about 1% (w/w) of the composition to about 3% (w/w) of the composition, from about 1% (w/w) of the composition to about 5% (w/w) of the composition, from about 1% (w/w) of the composition to about 8% (w/w) of the composition, from about 1% (w/w) of the composition to about 10% (w/w) of the composition, from about 3% (w/w) of the composition to about 5% (w/w) of the composition, from about 3% (w/w) of the composition to about 8% (w/w) of the composition, from about 3% (w/w) of the composition to about 10% (w/w) of the composition, from 5% (w/w) of the composition to about 8% (w/w) of the composition, From about 5% (w/w) of the composition to about 10% (w/w) of the composition or from about 8% (w/w) of the composition to about 10% (w/w) of the composition. In some embodiments, the polymer is about 1% (w/w) of the composition, about 3% (w/w) of the composition, about 5% (w/w) of the composition, about 8% (w/w) of the composition, or about 10% (w/w) of the composition. In some embodiments, the polymer is about 1% to about 8% (w/w) of the composition.

In some embodiments, the method further comprises heating the polymer solution to 60-70 ℃. In some embodiments, the method further comprises mixing the polymer solution with water using a rotating device. In some embodiments, the method further comprises mixing the polymer solution with a solution comprising polyvinyl alcohol (PVA), glutaraldehyde, methylene chloride, Octadecyltrichlorosilane (ODS), hydrochloric acid (HCl), or any combination thereof. In some embodiments, the method further comprises mixing the polymer solution with a glycerol solution to form a hollow fiber membrane.

In some embodiments, the polymer comprises polysulfone (polyfufone). In some embodiments, the polysulfone has an average molecular weight of about 40000 to about 100000. In some embodiments, the polysulfone has an average molecular weight of at least about 40000. In some embodiments, the polysulfone has an average molecular weight of up to about 100000. In some embodiments, the polysulfone has an average molecular weight of about 40000 to about 50000, about 40000 to about 60000, about 40000 to about 67000, about 40000 to about 75000, about 40000 to about 81000, about 40000 to about 90000, about 40000 to about 100000, about 50000 to about 60000, about 50000 to about 67000, about 50000 to about 75000, about 50000 to about 81000, about 50000 to about 90000, about 50000 to about 100000, about 60000 to about 67000, about 60000 to about 75000, about 60000 to about 81000, about 60000 to about 90000, about 67000 to about 75000, about 67000 to about 81000, about 67000 to about 90000, about 67000 to about 100000, about 75000 to about 81000, about 75000 to about 90000, about 100075000 to about 90000, about 10007500 to about 81000, about 90000 to about 90000, or about 90000 to about 100000. In some embodiments, the polysulfone has an average molecular weight of about 40000, about 50000, about 60000, about 67000, about 75000, about 81000, about 90000, or about 100000.

In some embodiments, the polysulfone is about 10% (w/w) to about 40% (w/w) of the composition. In some embodiments, the polysulfone is at least about 10% (w/w) of the composition. In some embodiments, the polysulfone is up to about 40% (w/w) of the composition. In some embodiments, the polysulfone is from about 10% (w/w) of the composition to about 20% (w/w) of the composition, from about 10% (w/w) of the composition to about 30% (w/w) of the composition, from about 10% (w/w) of the composition to about 40% (w/w) of the composition, from about 20% (w/w) of the composition to about 30% (w/w) of the composition, from about 20% (w/w) of the composition to about 40% (w/w) of the composition, or from about 30% (w/w) of the composition to about 40% (w/w) of the composition. In some embodiments, the polysulfone is about 10% (w/w) of the composition, about 20% (w/w) of the composition, about 30% (w/w) of the composition, or about 40% (w/w) of the composition.

In some embodiments, the polymer comprises Polysulfone (PSU), Polyetherimide (PEI), Polyethersulfone (PES), or any combination thereof.

In some embodiments, the method further comprises coating a support layer with the polymer solution. In some embodiments, the method further comprises contacting the inorganic solution comprising graphene oxide with Triethylamine (TEA), camphorsulfonic acid (CSA), dimethyl sulfoxide (DMSO), metaphenylene diamine (MPD), 2-ethyl-1, 3-hexanediol (EHD), sodium lauryl sulfate (SLES), or any combination thereof.

In some embodiments, the Triethylamine (TEA) is about 1% to about 4% (w/w) of the composition. In some embodiments, the camphorsulfonic acid (CSA) is from about 1% to about 5% (w/w) of the composition. In some embodiments, the dimethyl sulfoxide (DMSO) is about 1% to about 2% (w/w) of the composition. In some embodiments, the metaphenylene diamine (MPD) is from about 0.2% to about 3% (w/w) of the composition. In some embodiments, the 2-ethyl-1, 3-hexanediol (EHD) is about 0.1% to about 0.4% (w/w) of the composition. In some embodiments, sodium lauryl sulfate (SLES) comprises from about 0.1% to about 0.4% (w/w) of the composition.

In some embodiments, the method further comprises mixing the organic solution comprising graphene oxide with 1,3, 5-benzenetricarboxylic acid chloride (TMC), tributyl phosphate (TBP), or any combination thereof. In some embodiments, the 1,3, 5-benzenetricarboxylic acid chloride (TMC) is about 0.01% to about 0.1% (w/w) of the composition. In some embodiments, the tributyl phosphate (TBP) is about 0.1% to about 0.5% (w/w) of the composition.

It is to be understood that both the foregoing general description and the following detailed description are exemplary, but are not restrictive, of the disclosure.

Drawings

The present application is best understood from the following detailed description when read with the accompanying drawing figures. It is emphasized that, according to common practice, the various features of the drawings are not to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity. The drawings include the following figures:

fig. 1A shows a transmission electron microscope image of graphene oxide prepared using a sugar and an acid according to example 3;

figure 1B shows an atomic force microscope image at a first magnification of graphene oxide prepared according to example 3 using a sugar and an acid;

figure 1C shows an atomic force microscope image at a second magnification of graphene oxide prepared according to example 3 using a sugar and an acid;

fig. 2A shows a crude graphene oxide particle observed using an electron microscope;

fig. 2B shows graphene oxide particles obtained after using about 180 liters of an oxidizing solution, observed under an electron microscope;

FIG. 3 shows a composition of graphene oxide characterized using ultraviolet-visible spectroscopy;

fig. 4 shows a flow diagram of a method of preparing a graphene oxide composite ultrafiltration membrane;

fig. 5A shows a scanning electron microscope image of a cross-section of a graphene oxide-PVDF composite ultrafiltration hollow fiber membrane prepared according to example 6at a first magnification;

fig. 5B shows a scanning electron microscope image of a cross-section of a graphene oxide-PVDF composite ultrafiltration hollow fiber membrane prepared according to example 6at a second magnification;

fig. 5C shows a scanning electron microscope image of the surface of the graphene oxide-PVDF composite ultrafiltration hollow fiber membrane prepared according to example 6at a first magnification;

fig. 5D shows a scanning electron microscope image at a second magnification of the surface of a graphene oxide-PVDF composite ultrafiltration hollow fiber membrane prepared according to example 6;

fig. 6 shows a flow chart of a method of preparing a second graphene oxide composite ultrafiltration membrane;

fig. 7A shows a scanning electron microscope image of the surface of a graphene oxide-PSF composite ultrafiltration membrane prepared according to example 7 at a first magnification;

fig. 7B shows a scanning electron microscope image of the surface of the graphene oxide-PSF composite ultrafiltration membrane prepared according to example 7 at a second magnification;

FIG. 8 shows a flow diagram of a method of preparing a graphene oxide composite nanofiltration membrane;

FIG. 9 shows a flow diagram of a method of preparing a second graphene oxide composite nanofiltration membrane;

FIG. 10 shows a flow diagram of a method of making a graphene oxide composite polyamide selection layer;

fig. 11A shows a scanning electron microscope image at a first magnification of a surface of a graphene oxide composite reverse osmosis membrane prepared according to example 10;

fig. 11B shows a scanning electron microscope image at a second magnification of a surface of a graphene oxide composite reverse osmosis membrane prepared according to example 10; and

fig. 11C shows a scanning electron microscope image of the surface of the graphene oxide composite reverse osmosis membrane prepared according to example 10at a third magnification.

Detailed Description

Compositions, membranes, devices, and methods of making graphene oxide-containing water filtration systems are disclosed.

The term "about" and grammatical equivalents thereof in relation to a reference value used in this disclosure can include a range value of the value plus or minus 10%, for example, a range value of plus or minus 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, or 1% above the value. For example, a quantity of "about 10" includes a quantity from 9 to 11.

As used herein, the singular forms "a," "an," and "the" are intended to include the plural references unless the context clearly dictates otherwise. Accordingly, unless indicated to the contrary, the numerical parameters set forth in this disclosure are approximations that may vary depending upon the desired properties to be obtained by the embodiment.

Unless otherwise indicated, open-ended terms such as "comprising," "including," "having" and similar terms mean including.

The term "atomic percent" as used in this disclosure may refer to the percentage of an atom relative to the total number of atoms. The atomic percentages can be calculated as: atomic percent of N_i/N_tot×100％。

Examples

The following examples may more clearly illustrate the overall nature of the disclosure. The embodiments of the disclosure are illustrative and not restrictive.

Example 1 Synthesis of graphene oxide Using graphite powder

In this example, the graphite powder is subjected to mechanical pulverization and/or grinding treatment to obtain an ultrafine graphite powder having an average particle diameter of not more than 2 μm. 1 kg of ultrafine graphite powder and 5-10 kg of potassium permanganate powder are added to a reactor, the lining of which is coated with a polytetrafluoroethylene or glass coating and stirred continuously and homogeneously with a stirrer, cooled and kept at a constant temperature below 10 ℃. A total volume of 40-100 liters of concentrated sulfuric acid (e.g., greater than 94%) is slowly added and the mixture is stirred well for 15 minutes to 1 hour.

The reactor was heated to 40-50 ℃ and held at this temperature for 2-24 hours, then the reactor was cooled and held at a constant temperature below 10 ℃ and 40-200 kg of ice cubes made of deionized water were added to the reactor, stirring was continued until all the ice cubes melted and the solution temperature did not fluctuate any more. The volume ratio of deionized water to sulfuric acid may be 1: 1 to 1: 2.

the reaction was continued with stirring and 2-50 liters of hydrogen peroxide were added slowly until the solution turned yellow and no more gas was formed. The amount of hydrogen peroxide added may be proportional to the amount of potassium permanganate added.

The reactor is charged with 80-300 liters of an organic solution which may be a mixture of acetone, dichloromethane, hexane, carboxylic acid esters (e.g., ethyl acetate) and linear primary alcohols (e.g., butanol). The solution was stirred and heated continuously and kept at a constant temperature of 40-60 c, stirred for a further 0.5-4 hours, and finally the apparatus was cooled to room temperature and the stirring was stopped.

The solution in the reactor was partitioned. The upper layer is a brown organic solution containing graphene oxide formed by the reaction. The lower layer was a clear colorless liquid containing sulfuric acid and a small amount of hydrogen peroxide, with a partially crystalline solid.

The transparent liquid and solid in the lower layer were discharged. The brown organic solution is separated and subjected to a pressure filtration treatment by means of a pressure filter or an Electrodialysis (ED) method to obtain the final solid. And adding the solid into an ethanol, methanol, isopropanol or ethyl acetate solution, repeatedly washing and filtering to remove impurities such as sulfuric acid, and drying to obtain the graphene oxide powder with the diameter of tens to hundreds of nanometers. Graphene oxide powder is rich in hydrophilic functional groups (e.g., 35% -50% atomic oxygen percentage).

Example 2 Synthesis of graphene oxide Using sugar

Solid powders of 1-5 kg of mono-, DI-and/or polysaccharides, e.g. glucose, fructose or sucrose, are added to 1 liter of Deionized (DI) water, heated (to 50-80 ℃) and stirred to dissolve. The warm solution obtained was placed in a steel vessel. The steel vessel was sealed and then heated in a reaction furnace. The pressure in the steel container can reach 12-20atm when the steel container is heated to 160-220 ℃. After reacting for 2-5 hours, the steel vessel was cooled to room temperature, and the gas in the steel vessel was discharged to release the gas pressure. The reaction product in the steel vessel was taken out and subjected to a drying treatment to obtain a solid reaction product powder.

30-60 liters of concentrated sulfuric acid having a concentration greater than 94% is added to a reactor lined with a polytetrafluoroethylene or glass coating. The reactor was cooled and maintained at a constant temperature of about 0 ℃, stirring was started, then 1 kg of the reaction product powder was added, and the resulting mixture was uniformly stirred for 15 minutes to 1 hour, then 0.5 to 4 kg of potassium permanganate powder was slowly added to the mixture, and the mixture was controlled below 50 ℃, and the resulting mixture was sufficiently stirred for 15 minutes to 1 hour.

Heating the reactor to 40-50 ℃ and keeping the temperature constant, continuing to stir for 0.5-3 hours, then cooling the reactor to be lower than 10 ℃ and keeping the temperature constant, adding 30-60 kg of ice blocks made of deionized water, and continuing to stir until the temperature of the solution does not fluctuate.

Stirring was continued and 6-30 liters of hydrogen peroxide were added slowly until the solution turned yellow and no more gas was formed.

The solution is then subjected to a pressure filtration treatment by means of a pressure filter, or to a centrifugal separation treatment at a speed of 2000-. Adding the solid into ethanol or methanol solution, repeatedly washing and filtering to remove impurities such as sulfuric acid, and drying to obtain graphene oxide powder with the diameter of tens to hundreds of nanometers and rich in hydrophilic functional groups (the oxygen atom percentage is 35-50%). .

Example 3 Synthesis of graphene oxide Using sugar and acid

Adding carboxylic acid, oxalic acid, citric acid, phosphoric acid, benzoic acid, dihydroxybenzene and dopamine and a certain amount of monosaccharide, disaccharide or polysaccharide (such as glucose, fructose or sucrose) solid powder into deionized water, and stirring under heating (50-80 deg.C) to dissolve. The warm solution obtained was placed in a steel container, which was sealed and then heated in a reaction furnace. When the steel vessel is heated to 160-220 ℃, the pressure in the steel vessel can reach 12-20 atm. After reacting for 2-5 hours, the steel vessel was cooled to room temperature and the gas in the steel vessel was vented to release the gas pressure. And taking out a reaction product in the steel container, adding the reaction product into an ethanol or methanol solution, repeatedly washing and filtering to remove impurities, and drying to finally obtain graphene oxide powder which is tens of nanometers to several micrometers in diameter and is rich in hydrophilic functional groups (30% -40% of oxygen atom percentage). Fig. 1A shows a Transmission Electron Microscope (TEM) image of graphene oxide prepared using sugars and acids according to example 3. Fig. 1B and 1C show Atomic Force Microscope (AFM) images of graphene oxide prepared using sugars and acids according to example 3.

Example 4 Synthesis of graphene oxide Using multiple Oxidation Steps

First oxidation: 1 kg of graphite powder was mixed with 30-60 l of concentrated sulfuric acid having a concentration of more than 94% and stirred at a constant temperature of less than 10 ℃ for 30 minutes. 5-10 kg of potassium permanganate powder was added to the mixture and stirred for 15 minutes to 1 hour while cooling, and then heated to 40-50 ℃ to further react for 2-8 hours. After the reaction, the remaining sulfuric acid and potassium permanganate solution (oxidant) is recycled through pressure filtration or vacuum filtration process to obtain solid reaction product powder. The solid reaction product powder was then added to 60 kg of ice and stirring was maintained until all the ice was completely melted and the powder was completely dissolved in the solution. Then 2-4 liters of hydrogen peroxide are added to the solution and the solution is continuously stirred until no more gas is produced in the solution. The solution is then allowed to settle for several hours to allow precipitation to occur or is subjected to a centrifugation process to obtain a precipitate. The precipitate is then dried at 30-40 ℃ to obtain a solid powdered product: primarily made Graphene Oxide (GO).

And (3) second oxidation: 1 kg of the as-prepared graphene oxide was added to 60 liters of an oxidizing agent solution (a mixed solution of sulfuric acid and potassium permanganate, in the same ratio as in the previous step), and dispersion treatment was performed by a ball mill or an acoustic bath. The diameter of the finally obtained graphene oxide can be controlled by the amount of the oxidant solution (60-300 liters).

The uniformly dispersed solution was heated to 40-50 ℃ with stirring, further reacted for 2-8 hours, and then mixed with 120-600 kg of ice cubes and diluted with stirring. 2-20 liters of hydrogen peroxide are added to the solution and the solution is continuously stirred until no more gas is formed in the solution.

The solution is then subjected to a pressure filtration treatment by a pressure filtration or Electrodialysis (ED) method to obtain solid graphene oxide. Then adding the solid graphene oxide into an ethanol, methanol, isopropanol or ethyl acetate solution, repeatedly washing and filtering to remove impurities such as sulfuric acid, and then drying at 30-40 ℃ to finally obtain graphene oxide powder rich in hydrophilic functional groups (the oxygen atom percentage is 40% -50%), wherein the diameter of the graphene oxide powder ranges from tens of nanometers to hundreds of nanometers.

Example 5 characterization of graphene oxide

Particle sizes were compared using an electron microscope. As shown in fig. 2A, it shows a primary graphene oxide particle using an electron microscope, the diameter of the primary graphene oxide being in the range of hundreds of nanometers to tens of micrometers. As shown in fig. 2B, when about 180 liters of the oxidation solution was used, the diameter of the graphene oxide obtained after the second oxidation process was 300-500 nm.

From top to bottom at a wavelength of 230 nanometers: respectively, as-prepared graphene oxide, graphene oxide prepared using 120, 180 and 240 liters of oxidizing solution. The composition of graphene oxide was characterized using uv-vis spectroscopy.

As shown in fig. 3, the composition of graphene oxide was characterized using uv-vis spectroscopy. In the uv-vis spectrum, the peak intensity of graphene oxide is different compared to that of the original graphene oxide. The primary graphene oxide forms a pi-pi x transition peak at a wavelength of 230 nm, which can be used as an index of the primary graphene oxide due to the aromatic structure of the primary graphene oxide. The peak intensity of the graphene oxide sample prepared in example 4 at a wavelength of 230 nm is lower than that of the original graphene oxide synthesized by the conventional Hummers method, because the graphene oxide has a small diameter and poor aromatic characteristics. The curves in fig. 3 reflect the original graphene oxide, the graphene oxide prepared using 180, 120 and 240 liters of oxidizing solution, respectively, from top to bottom at a wavelength of 230 nanometers. As the amount of the oxidizing solution used in the reaction increases, the particle size and the oxygen atom percentage of the graphene oxide decrease.

Example 6 preparation of graphene oxide composite Ultrafiltration Membrane

Adding graphene oxide powder into an organic solvent N, N-Dimethylacetamide (DMAC), N-methyl-2-pyrrolidone (nano P) or Dimethylformamide (DMF) and stirring, then uniformly dispersing single-layer or few-layer graphene oxide in the organic solvent DMAC, nano P, NEP or DMF, and repeating for at least three times under the pressure of 15000-20000psi by using a high-pressure homogenizer to prepare the organic solution A dispersed with the graphene oxide.

Adding graphene oxide powder into deionized water and stirring, then uniformly dispersing single-layer or few-layer graphene oxide in an inorganic solvent in the deionized water, and repeating for at least three times by using a high-pressure homogenizer under the pressure of 15000-20000psi to prepare an inorganic solution B dispersed with the graphene oxide.

Fig. 4 shows a process of preparing a graphene oxide composite ultrafiltration membrane. Poly (vinyl pyrrolidone) (PVP molecular weight 8-2000kDa), triethyl phosphate (TEP), Ethylene Glycol (EG), polyethylene glycol (PEG), and perfluorosulfonic acid were added to the melting kettle along with solid particles of polyvinylidene fluoride (PVDF) and organic solution a in which graphene oxide was dispersed. PVDF is a combination of various PVDF particles having molecular weights in the range of 300000-. The mixture was then heated and maintained at a constant temperature of 40-70 ℃ with continuous stirring for several hours until all the starting materials were completely dissolved and homogeneously mixed. Thereafter, the solution was passed from the melting tank to the spinning tank, and degassed under negative pressure to remove air bubbles at a constant temperature of 40 to 70 ℃ to obtain a PVDF solution.

A dry-wet spinning process and a spinning system apparatus are used to manufacture a hollow fiber membrane (dry-jet-wet spinning process by a non-solvent induced phase separation method through a batch-type wet spinning machine). The PVDF solution in the spinning kettle is extruded into water (pure water containing a certain amount of inorganic solution B) at 5-30 ℃ in a No. 1 condensation tank by using a spinneret through compressed gas, and the phase conversion is carried out after the extruded solution is contacted with the water to obtain brown linear solid. Using a wire winding system, the linear solids were connected, slowly pulled out, and introduced into a mixed solution of methanol or ethanol and water in the No. 2 coagulation tank to be soaked for a certain period of time, then slowly pulled out, and then sequentially immersed in the No. 3 reaction tank, the No. 4 reaction tank, and the No. 5 washing tank in the same manner for a certain period of time. The reaction tank No. 3 and the reaction tank No. 4 are respectively aqueous solutions or organic solutions composed of polyvinyl alcohol (PVA), glutaraldehyde, an inorganic solution B in which graphene oxide is dispersed, dichloromethane, Octadecyltrichlorosilane (ODS) and hydrochloric acid (HCl). The No. 5 washing tank contains an aqueous glycerol solution. The linear solid was taken out from the No. 5 washing tank to obtain a hollow fiber ultrafiltration membrane as a final product. Fig. 5A and 5B are Scanning Electron Microscope (SEM) images of a cross section of a graphene oxide-PVDF composite ultrafiltration hollow fiber membrane. Fig. 5C and 5D are SEM images of the surface of the graphene oxide-PVDF composite ultrafiltration hollow fiber membrane.

The inner diameter of the graphene oxide composite hollow fiber ultrafiltration membrane is 0.6-0.8mm, and the outer diameter is 1.2-1.4 mm. The water contact angle of the surface of the film is 40-60 degrees. According to different chemical formula ratios, the pore diameter of the membrane surface can be adjusted between 10 and 100 nanometers; the porosity is 70-90%; the water flux is 400-600 LMH/bar.

Graphene oxide has a large number of hydrophilic functional groups, such as carboxyl, epoxy and hydroxyl groups, on the surface and edges thereof, and thus the linkage of these groups to the surface of a polymer molecular chain can improve the hydrophilicity of the surface, increase the permeation efficiency of water, and can effectively prevent contamination caused by attachment and reproduction of organisms due to low interfacial energy between the surface and water. In addition, the functional group of graphene ensures a relatively high negative electromotive force, which can also prevent the adhesion and accumulation of dust on the surface of the membrane. This can extend the service time or cleaning cycle of the ultrafiltration membrane by a factor of 2-5.

Hydrophilic functional groups can trap water molecules to form a water-moisture layer at the surface of the membrane, so that most lipophilic contaminants and bacteria cannot or are less likely to adhere to the surface of the membrane. Therefore, the antifouling property of the entire film and the restorability after the back washing can be improved. Hydrophilicity may inhibit hydrophobic-hydrophobic interactions between bacteria and membrane surfaces. The negatively charged membrane surface is capable of producing electrostatic repulsion of negatively charged bacteria and Extracellular Polymers (EPS).

Example 7-preparation of another graphene oxide composite Ultrafiltration Membrane

Fig. 6 shows a process for preparing a second graphene oxide composite ultrafiltration membrane. 10-25 wt% of Polysulfone (PSU), poly (oxybenzene sulfone), Polyetherimide (PEI) and Polyethersulfone (PES) were added to a melting kettle along with an amount of polyethylene glycol (PEG) and organic solution a dispersed with graphene oxide. Polysulfones are a combination of various polysulfone particles with molecular weights ranging from 67000-81000. The mixture was then heated and maintained at a constant temperature of 40-70 ℃ with continuous stirring for several hours until all the starting materials were completely dissolved and homogeneously mixed. Thereafter, the solution was degassed under negative pressure to remove air bubbles at a constant temperature of 40 to 70 ℃, thereby obtaining a polysulfone solution.

The polypropylene nonwoven fabric support layer is pre-wetted with an organic solvent, N-Dimethylacetamide (DMAC), N-methyl-2-pyrrolidone (nano-P), or Dimethylformamide (DMF), and then the polysulfone solution is coated on the nonwoven fabric surface using a microabrader or a cast knife. The coated nonwoven fabric was then immersed in 5-30 ℃ water (pure water containing a certain amount of the inorganic solution B) in a coagulation tank No. 1, during which the polysulfone solution was solidified by phase inversion, thereby producing an ultrafiltration membrane layer on the surface of the nonwoven fabric. The film pieces were removed, excess liquid was removed from the film surfaces with an air knife, and the film pieces were dried by baking in an oven at 40-60 c, and then the dried film pieces were immersed again in the solution in reaction tank No. 2. The solution consists of polyvinyl alcohol (PVA), glutaraldehyde, an inorganic solution B in which graphene oxide is dispersed, dichloromethane, Octadecyltrichlorosilane (ODS) and hydrochloric acid (HCl). Taking out the immersed membrane, removing excessive liquid from the surface of the membrane by using an air knife, and then immersing and cleaning the membrane in a mixed solution of methanol or ethanol and water in a No. 3 washing tank again. The washed membrane pieces were taken out, excess liquid was removed from the membrane surfaces with an air knife, and the membrane pieces were dried by baking in an oven at 40-60 c, and then immersed again in purified water in No. 4 sink for immersion washing. And finally, taking out the cleaned membrane, removing redundant liquid from the surface of the membrane by using an air knife, and baking and drying the membrane in a drying oven at the temperature of 40-60 ℃ to obtain the final product, namely the planar ultrafiltration membrane. The membrane surface water contact angle of the graphene oxide composite planar ultrafiltration membrane is 40-60 degrees. According to different chemical formula ratios, the pore diameter of the membrane surface can be adjusted between 10 and 100 nanometers; the porosity is 70-90%; the water flux is 400-600 LMH/bar. Fig. 7A and 7B are Scanning Electron Microscope (SEM) images of the membrane surface at two different magnifications.

Example 8 preparation of graphene oxide composite nanofiltration Membrane

Fig. 8 illustrates a method of preparing a graphene oxide composite nanofiltration membrane. Poly (vinyl pyrrolidone) (PVP molecular weight 8-2000kDa), triethyl phosphate (TEP), Ethylene Glycol (EG), polyethylene glycol (PEG) and dopamine were added to a melting kettle together with 15-30 wt% of solid particles of Polyethersulfone (PES) and organic solution a in which graphene oxide was dispersed. The polyethersulfone was a combination of various polyethersulfone particles having molecular weights in the range of 45000-68000. The mixture was then heated and maintained at a constant temperature of 40-70 ℃ with continuous stirring for several hours until all the starting materials were completely dissolved and homogeneously mixed. Thereafter, the solution was passed from the melting tank into a spinning tank and degassed under negative pressure to remove air bubbles at a constant temperature of 40-70 ℃ to obtain a polyethersulfone solution.

The hollow fiber membrane is manufactured using a dry-wet spinning process and a spinning system apparatus (dry-jet-wet spinning process using a spinning system). The polyether sulfone solution in the spinning kettle is extruded into water (containing a certain amount of pure water of the inorganic solution B) with the temperature of 5-30 ℃ in a No. 1 condensation tank by compressed gas by using a spinneret plate, and the phase conversion is carried out after the extruded solution is contacted with the water to obtain brown linear solid. The linear solid is connected by using a winding system, slowly pulled out, guided to a mixed solution of methanol or ethanol and water in a No. 2 coagulation tank to be soaked for a period of time, then slowly pulled out, and then sequentially soaked in a No. 3 reaction tank, a No. 4 reaction tank and a No. 5 washing tank for a period of time in the same manner. The reaction tank No. 3 and the reaction tank No. 4 are respectively aqueous solutions or organic solutions composed of polyvinyl alcohol (PVA), glutaraldehyde, an inorganic solution B in which graphene oxide is dispersed, dichloromethane, Octadecyltrichlorosilane (ODS) and hydrochloric acid (HCl). The No. 5 washing tank contains an aqueous glycerol solution. The linear solid was taken out from the No. 5 washing tank to obtain a hollow fiber ultrafiltration membrane as a final product.

The inner diameter of the graphene oxide composite hollow fiber ultrafiltration membrane is 0.6-0.8mm, and the outer diameter is 1.2-1.4 mm. The water contact angle of the surface of the film is 40-60 degrees. According to different chemical formula ratios, the pore diameter of the membrane surface can be adjusted between 1 and 10 nanometers; the water flux is 20-120 LMH/bar.

Example 9 preparation of another graphene oxide composite nanofiltration Membrane

Fig. 9 illustrates a method of preparing a second graphene oxide composite nanofiltration membrane. Poly (vinyl pyrrolidone) (PVP molecular weight 8-2000KDa), triethyl phosphate (TEP), Ethylene Glycol (EG), polyethylene glycol (PEG) and dopamine were added to a melting kettle together with 15-30 wt% of solid particles of polyethersulfone and organic solution a in which graphene oxide was dispersed. The polyethersulfones are a combination of various polyethersulfone particles having molecular weights ranging from 45000-68000. The mixture was then heated and maintained at a constant temperature of 40-70 ℃ with continuous stirring for several hours until all the starting materials were completely dissolved and homogeneously mixed. Thereafter, the solution was passed from the melting tank into a spinning tank and degassed under negative pressure to remove air bubbles at a constant temperature of 40-70 ℃ to obtain a polyethersulfone solution.

The polypropylene nonwoven fabric support layer is pre-wetted with an organic solvent, N-Dimethylacetamide (DMAC), N-methyl-2-pyrrolidone (nano-P), or Dimethylformamide (DMF), and then the polysulfone solution is coated on the nonwoven fabric surface using a microabrader or a cast knife. The coated nonwoven fabric was then immersed in water (pure water containing a certain amount of the inorganic solution B) at 5 to 30 ℃ in a coagulation tank No. 1, during which the polysulfone solution was solidified by phase inversion, thereby producing a nano-filtration film layer on the surface of the nonwoven fabric. The film sheet is removed, excess liquid is removed from the film surface with an air knife, and the film sheet is dried by baking in an oven at 40-60 ℃. Then, the dried membrane was immersed again in a solution consisting of polyvinyl alcohol (PVA), glutaraldehyde, an inorganic solution B in which graphene oxide was dispersed, dichloromethane, Octadecyltrichlorosilane (ODS), and hydrochloric acid (HCl) in reaction tank No. 2. Taking out the immersed membrane, removing excessive liquid from the surface of the membrane by using an air knife, and then immersing and cleaning the membrane in a mixed solution of methanol or ethanol and water in a No. 3 washing tank again. The washed membrane pieces were taken out, excess liquid was removed from the membrane surfaces with an air knife, and the membrane pieces were dried by baking in an oven at 40-60 c, and then immersed again in purified water in No. 4 sink for immersion washing. And finally, taking out the cleaned membrane, removing redundant liquid from the surface of the membrane by using an air knife, and baking and drying the membrane in an oven at the temperature of 40-60 ℃ to obtain the planar nanofiltration membrane as a final product. The water contact angle of the surface of the graphene oxide composite nanofiltration membrane is 40-60 degrees. According to different chemical formula ratios, the pore diameter of the membrane surface can be adjusted between 1 and 10 nanometers; the water flux is 20-120 LMH/bar.

Example 10 preparation of graphene oxide reverse osmosis Membrane

The graphene oxide reverse osmosis membrane may have a graphene oxide composite ultrafiltration membrane support layer (e.g., using the same method as example 7) and a graphene oxide composite polyamide selection layer.

Adding graphene oxide powder to a cycloalkanone or an organic solvent alkane such as hexane, isoparaffin, light alkylated naphtha or cyclohexanone, stirring, uniformly dispersing a single layer or a small layer of graphene oxide in the organic solvent alkane or the cycloalkanone such as hexane, isoparaffin, light alkylated naphtha or cyclohexanone, and repeating at least three times at a pressure of 15000-.

Fig. 10 illustrates a method of making a graphene oxide composite polyamide selective layer. To the inorganic solution B in which graphene oxide is dispersed, 1 to 4 wt% of Triethylamine (TEA), 1 to 5 wt% of camphorsulfonic acid (CSA), 0.5 to 6 wt% of m-phenylenediamine (MPD), a certain amount of dimethyl sulfoxide (DMSO), 2-ethyl-1, 3-hexanediol (EHD), sodium lauryl sulfate (SLES), 2-ethylhexanol, dioctyl fumarate, di (2-ethylhexyl) adipate, polyethylene glycol (PEG), octanoic acid, 1,2, 3-propanetriol ester, dioctyl phthalate, simethicone, ethanol, methanol and isopropanol were added, respectively, to obtain a solution D.

0.01-0.2% of 1,3, 5-benzenetricarboxylic acid chloride (TMC), 0.1-0.5 wt% of tributyl phosphate (TBP), and the organic solution C in which graphene oxide is dispersed are added to an alkane or a cycloalkanone, for example, hexane, isoparaffin, light alkylated naphtha, or cyclohexanone, and sufficiently dissolved with stirring to obtain a solution E.

And immersing the graphene oxide composite ultrafiltration membrane into the solution D in the No. 5 reaction tank for thorough immersion, then taking out, removing redundant solution D on the surface of the membrane by using an air knife or a butadiene rubber roller, and then immersing the ultrafiltration membrane into the solution E in the No. 6 reaction tank so that the solution D in the gap of the ultrafiltration membrane is diffused to the surface of the membrane to contact with the solution E and carry out interfacial polymerization reaction, thereby forming the graphene oxide composite polyamide selection layer.

Removing the membrane from the No. 6 reaction tank, soaking and cleaning the membrane in organic solvent alkane or cyclic alkanone such as hexane, isoparaffin, light alkyl naphtha or cyclohexanone in No. 7 washing tank, baking and drying in oven at 40-60 deg.C, and soaking in sodium hypochlorite NaOCl and Na in No. 8 tank respectively₂CO₃Soaking and cleaning in water solution and pure water in tank No. 9, and baking in an oven at 40-60 deg.C for drying to obtain planar reverse osmosis membrane as final product.

The water contact angle of the membrane surface of the graphene oxide composite reverse osmosis membrane is 40-60 degrees. When using 2000ppm sodium chloride solution, the water flux is up to 3-5.4LMH/bar at a pressure of 15.5 bar; the salt rejection rate reaches 99 percent.

Graphene oxide has a large number of hydrophilic functional groups, such as carboxyl, epoxy and hydroxyl groups, on the surface and edges thereof, which can significantly improve the surface hydrophilicity, electronegativity and surface smoothness of the membrane, and thus the graphene oxidation enhanced membrane has higher water permeability. In addition, the hydrophilic functional groups can trap water molecules to form a water-moisture layer on the membrane surface, and by cooperating with improved surface smoothness, make lipophilic contaminants and bacteria unable or less likely to adhere to the membrane surface. Therefore, the antifouling property of the entire film and the restorability after the back washing can be improved. In addition, the functional group of graphene ensures a relatively high negative electromotive force, which can also prevent the adhesion and accumulation of dust on the surface of the membrane. This can extend the service time or cleaning cycle of the ultrafiltration membrane by a factor of 2 to 3. Fig. 11A, 11B, and 11C are SEM images of the surface of the graphene oxide composite reverse osmosis membrane at three different magnifications.

While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will occur to those skilled in the art without departing from the invention herein. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.