阅读说明：本技术 一种改性膨润土及其制备方法和应用 (Modified bentonite and preparation method and application thereof ) 是由 王齐 汪思孝 任伟华 周琳 郁晨阳 于 2020-05-15 设计创作，主要内容包括：本发明公开了一种改性膨润土及其制备方法和应用,将膨润土原料放入蒸馏水溶解后通过加入甲基纤维素和硫酸分别对膨润土进行表面活化,再通过硫酸处理,削弱膨润土的层间键能,初步扩大层距,再加入三甲基苄基氯化铵通过离子交换进入被扩大的膨润土片层间,最后加入十二烷基硫酸钠生成气泡,再经过超声波清洗,增加气泡量,使得改性膨润土有更多的孔数。通过本发明制成的改性膨润土具有更大的比表面积和更强的吸附能力,用在漆雾凝聚剂中凝聚上浮率提高,COD含量降低,透视度提高。(The invention discloses a modified bentonite and a preparation method and application thereof, which are characterized in that bentonite raw materials are put into distilled water for dissolving, then methyl cellulose and sulfuric acid are added for respectively carrying out surface activation on the bentonite, then sulfuric acid treatment is carried out, the interlayer bond energy of the bentonite is weakened, the interlayer distance is preliminarily enlarged, trimethyl benzyl ammonium chloride is added into the enlarged bentonite interlayer through ion exchange, finally sodium dodecyl sulfate is added to generate bubbles, and the amount of the bubbles is increased through ultrasonic cleaning, so that the modified bentonite has more holes. The modified bentonite prepared by the method has larger specific surface area and stronger adsorption capacity, and the coagulation and floating rate is improved, the COD content is reduced and the transmittance is improved when the modified bentonite is used in a paint mist coagulant.)

1. The preparation method of the modified bentonite is characterized by comprising the following steps:

s1: taking a bentonite raw material, putting the bentonite raw material into distilled water for dissolving and stirring, adding methyl cellulose during stirring, slowly stirring for 0.5-1h, standing, and taking out an upper layer suspension to obtain bentonite slurry;

s2: adding sodium chloride into the bentonite slurry obtained in the step S1, heating and stirring for 2-3h at 50-55 ℃, filtering, drying in a drying box, adding sulfuric acid, heating for 1-2h at 50-70 ℃, filtering, washing and drying for later use;

s3: mixing and grinding the bentonite obtained in the step S2, trimethyl benzyl ammonium chloride and N-methylformamide, adding distilled water, stirring to form a suspension, heating for 1-2h, and cooling for later use;

s4: and (4) adding sodium dodecyl sulfate into the suspension formed by stirring in the step S3, stirring uniformly, naturally airing for 1-2h, then putting into a closed container, putting the closed container into an ultrasonic cleaner, continuously cleaning for 0.15-0.5h, taking out, putting into an oven, drying and forming, and preparing into the modified bentonite.

2. The method for preparing modified bentonite according to claim 1, wherein the bentonite raw material in the step S1 is 90-110 parts by weight of sodium bentonite, the methylcellulose is 15-20 parts by weight, the sodium chloride in the step S2 is 5-10 parts by weight, the sulfuric acid is 120-150 parts by weight, the trimethyl benzyl ammonium chloride in the step S3 is 15-25 parts by weight, the N-methyl formamide is 3-8 parts by weight, and the sodium dodecyl sulfate in the step S4 is 0.5-1.5 parts by weight.

3. The method for producing modified bentonite according to claim 2, wherein the concentration of the sulfuric acid is 30 to 60%.

4. The method as claimed in claim 1, wherein the heating temperature in step S3 is 150-180 ℃.

5. The method for producing modified bentonite according to claim 1, wherein the cleaning frequency of the ultrasonic cleaner in step S4 is 35kHz to 45 kHz.

6. The method for preparing modified bentonite according to claim 1, wherein the drying temperature in the step S4 is 90-100 ℃.

7. A modified bentonite, which is characterized by being prepared by the method for preparing the modified bentonite according to any one of claims 1 to 6.

8. Use of a modified bentonite as claimed in claim 7 in paint mist coagulants.

Technical Field

The invention relates to the field of water treatment coagulants, in particular to modified bentonite and a preparation method and application thereof.

Background

The equipment is exposed in air or external environment for a long time, corrosion or other chemical reactions are easy to occur, the equipment is damaged, the service life and the functions of the equipment are influenced, so that paint needs to be sprayed on the surface or the wall surface of the equipment, an air paint spraying mode is adopted at first, a large amount of paint mist and organic solvent gas are generated in the air paint spraying process, the health of operators is influenced, and the surrounding environment and air are seriously polluted.

In the 80 s, the coating system of the wind pressure-water washing type paint spray booth began to be used domestically, so that the coating mode was leaped, the coating quality was greatly improved, and the pollution to the environment was greatly reduced, however, if the wind pressure-water washing type paint spray booth did not use the paint mist coagulant, the paint entering the circulating water was not de-pasted and coagulated, and could be adhered to the inside of the equipment, the pipeline and the pump body, so as to cause the blockage of the water path and the gas path, so that the purification system could not normally operate.

Chinese patent CN103693724A discloses a paint mist treating agent and a preparation method thereof. The paint mist treating agent is specially used for removing paint in circulating water of a water curtain spray booth, has quick and effective viscosity elimination and good coagulation and floating functions on water-soluble and fat-soluble coatings, and has the advantages of less consumption of treating paint-containing waste water, simple preparation process, convenient operation for treating paint spraying waste water, non-sticky and odorless paint slag, easy subsequent treatment and the like compared with the prior art. The paint slag can not float up to the water surface completely, and a small amount (about 5 percent) of the paint slag is suspended in the circulating water or sinks to the water bottom, so that the turbidity or the transmittance of the circulating water cannot reach the standard.

In the prior art, the bentonite type paint mist coagulant uses common bentonite particles, the surface activity of the bentonite type paint mist coagulant is low, the number of pores is small, the specific surface area is small, the A agent of the formed bentonite type paint mist coagulant has poor adsorption and wrapping effects on paint mist, the mutual adhesion rate of the paint mist is high, the viscosity breaking effect is poor, and the bentonite type paint mist coagulant has poor treatment efficiency on paint mist sewage and needs to be improved urgently.

Disclosure of Invention

In order to overcome the defects in the prior art, the embodiment of the invention provides modified bentonite for a paint mist coagulant and a preparation method thereof, so that the modified bentonite has higher surface activity, more pores, larger specific surface area and stronger adsorption capacity, and is applied to the paint mist coagulant.

The embodiment of the application discloses: a preparation method of modified bentonite comprises the following steps:

s1: taking a bentonite raw material, putting the bentonite raw material into distilled water for dissolving and stirring, adding methyl cellulose during stirring, slowly stirring for 0.5-1h, standing, and taking out an upper layer suspension to obtain bentonite slurry;

s2: adding sodium chloride into the bentonite slurry obtained in the step S1, performing sodium modification to improve the suspension property and the dispersibility of the bentonite slurry, heating and stirring for 2-3h at 50-55 ℃, filtering, putting into a drying oven for drying, adding sulfuric acid, heating for 1-2h at 50-70 ℃, filtering, washing, and drying for later use;

s3: mixing and grinding the bentonite obtained in the step S2, trimethyl benzyl ammonium chloride and N-methylformamide, adding a proper amount of distilled water, stirring to form a suspension, heating for 1-2 hours, and cooling for later use;

s4: and (4) adding sodium dodecyl sulfate into the suspension formed by stirring in the step S3, stirring uniformly, naturally airing for 1-2h, then putting into a closed container, putting the closed container into an ultrasonic cleaner, continuously cleaning for 0.15-0.5h, taking out, putting into an oven, drying and forming, and preparing into the modified bentonite.

Preferably, the bentonite raw material in the step S1 is 90-110 parts by weight of sodium bentonite, the methylcellulose is 15-20 parts by weight, the sodium chloride in the step S2 is 5-10 parts by weight, the sulfuric acid is 150 parts by weight, the trimethyl benzyl ammonium chloride in the step S3 is 15-25 parts by weight, the N-methyl formamide is 3-8 parts by weight, and the sodium dodecyl sulfate in the step S4 is 0.5-1.5 parts by weight.

Preferably, the concentration of the sulfuric acid is 30-60%.

Preferably, the heating temperature in the step S3 is 150-180 ℃.

Preferably, the cleaning frequency of the ultrasonic cleaner in the step S4 is 35kHz to 45 kHz.

Preferably, the drying temperature in the step S4 is 90-100 ℃.

The invention also discloses modified bentonite prepared by the preparation method of the modified bentonite, which is applied to a paint mist coagulant.

The invention has the following beneficial effects: according to the modified bentonite prepared by the invention, the surface activation is respectively carried out on the bentonite by adding the methylcellulose and the sulfuric acid, so that the surface activity can be improved, the interlayer bond energy of the bentonite can be weakened through acid treatment, the interlayer distance is preliminarily enlarged, and a porous active substance with a micropore grid structure and a large specific surface area is formed;

then trimethyl benzyl ammonium chloride is added to enter between expanded bentonite lamella through ion exchange, so that the affinity between the surface between the lamellae and N-methylformamide is improved, and after the surface of the bentonite lamella is combined with the N-methylformamide, macromolecules enter to further increase the space between the bentonite lamella, so that the microstructure is looser;

finally, after the bentonite system is added into the sodium dodecyl sulfate, a large amount of bubbles are generated in the bentonite, and after the bentonite is regularly vibrated by an ultrasonic cleaner, the bubbles in the bentonite are further crushed, the number of the bubbles is increased, the bubbles are distributed more uniformly and densely, so that the formed modified bentonite has more pores, larger specific surface area and stronger adsorption capacity.

The modified bentonite prepared by the method has more pores, larger specific surface area and stronger adsorption capacity, and after the modified bentonite is added into a bentonite paint mist coagulant system, the paint mist coagulant of the modified bentonite is applied to improve the coagulation floating rate, reduce the COD content and improve the visibility, so that the paint and the oil paint in sewage treatment can be effectively removed.

In order to make the aforementioned and other objects, features and advantages of the invention more comprehensible, preferred embodiments accompanied with figures are described in detail below.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.