阅读说明：本技术 全氟烷基和多氟烷基吸着剂材料和使用方法 (Perfluoroalkyl and polyfluoroalkyl sorbent materials and methods of use ) 是由 丽贝卡·L·迪斯泰法诺 理查德·A·敏那 于 2020-04-03 设计创作，主要内容包括：公开了用钙、镁、锶或钡的离子、盐、氧化物、氢氧化物或碳酸盐处理的吸着剂材料可用于从液体和气体去除全氟烷基和多氟烷基物质(PFAS)、全氟辛酸(PFOA)、全氟辛烷磺酸(PFOS)、2,3,3,3,-四氟-2-(七氟丙氧基)丙酸盐和七氟丙基1,2,2,2-四氟乙基醚及类似化合物。如相对于未经处理的吸着剂材料所测量的,采用了所公开的处理的吸着剂材料提供改进的性能。(Sorbent materials treated with ions, salts, oxides, hydroxides or carbonates of calcium, magnesium, strontium or barium are disclosed as being useful for the removal of perfluoroalkyl and polyfluoroalkyl species (PFAS), perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), 2,3,3, -tetrafluoro-2- (heptafluoropropoxy) propionate and heptafluoropropyl 1,2,2, 2-tetrafluoroethyl ether and similar compounds from liquids and gases. The sorbent materials employing the disclosed treatments provide improved performance as measured relative to untreated sorbent materials.)

1. A method for removing perfluoroalkyl and polyfluoroalkyl materials (PFAS) from a liquid or gas, the method comprising:

providing a first sorbent material comprising from about 0.5 wt% to about 25 wt% of an ion, salt, oxide, hydroxide, or carbonate of magnesium, calcium, strontium, barium, or a combination or compound thereof, thereby increasing the sorption capacity of the sorbent material for perfluoroalkyl and polyfluoroalkyl species (PFAS) relative to a sorbent material that does not comprise the ion, salt, oxide, hydroxide, or carbonate; and

contacting the first sorbent material with a liquid or gas containing the PFAS.

2. The method of claim 1, wherein the first sorbent material comprises one or more of carbonaceous carbon, activated carbon, reactivated carbon, and carbon black.

3. The method of claim 2, wherein the carbonaceous carbon, activated carbon, reactivated carbon, or carbon black is formed from at least one of bituminous coal, sub-bituminous coal, lignite, anthracite, wood chips, sawdust, peat, nut shells, fruit pits, coconut shells, babassu nuts, macadamia nuts, african oil palm nuts, peach pits, cherry pits, olive pits, walnut shells, wood, lignin, polymers, nitrogen-containing polymers, resins, petroleum pitch, bagasse, rice hulls, corn husks, wheat and grain hulls, graphene, carbon nanotubes, or polymer fibers.

4. The method of claim 2, wherein the first sorbent material is reactivated carbon.

5. The method of claim 2, wherein the first sorbent material is reagglomerated activated carbon.

6. The method of claim 1, further comprising:

providing a second sorbent material comprising one or more of carbonaceous carbon, activated carbon, reactivated carbon, carbon black, natural zeolite, synthetic zeolite, silica gel, alumina clay, zirconia, diatomaceous earth, and metal oxides, and

contacting the second sorbent material with the liquid or gas containing the PFAS.

7. The method of claim 1, wherein the first sorbent material comprises one or more of magnesium oxide, calcium oxide, strontium oxide, or barium oxide.

8. The method of claim 7, wherein the first sorbent material comprises one or more of MgO or CaO.

9. The method of claim 1, wherein the ions, salts, oxides, hydroxides, or carbonates of the first sorbent material are introduced into the first sorbent material by one or more of dry mixing, wet impregnation, chemical vapor deposition, or physical vapor deposition.

10. The method of claim 1, wherein the first sorbent material comprises from about 1 wt% to about 20 wt% of an ion, salt, oxide, hydroxide, or carbonate of magnesium, calcium, strontium, barium, or a combination or compound thereof.

11. The method of claim 10, wherein the first sorbent material comprises from about 2 wt% to about 8 wt% of an ion, salt, oxide, or carbonate of magnesium, calcium, strontium, barium, or a combination or compound thereof.

12. The method of claim 1, wherein the first sorbent material is a reactivated carbon comprising ions, oxides, or carbonates of calcium, magnesium, sodium, potassium, and zinc, and the reactivated carbon has not been subjected to any process to remove or reduce the amount of the ions, oxides, or carbonates of calcium, magnesium, sodium, potassium, and zinc.

13. The method of claim 12, wherein the reactivated carbon has not been subjected to any acid wash that removes or reduces the amount of ions, oxides, or carbonates of the calcium, magnesium, sodium, and zinc.

Background

Perfluoroalkyl and polyfluoroalkyl materials (PFAS) are a group of compounds including perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS) and compounds produced by the GENX process such as 2,3,3,3, -tetrafluoro-2- (heptafluoropropoxy) propionate and heptafluoropropyl 1,2,2, 2-tetrafluoroethyl ether. Over the years, such highly fluorinated compounds have enjoyed widespread industrial use due to their chemical durability, excellent surfactant properties, and critical role as precursors to fluoropolymers, including polytetrafluoroethylene.

Unfortunately, these same properties make PFAS resistant to degradation in the environment while leading to bioaccumulation when ingested over time. Some recent studies have linked PFAS to various detrimental health effects, most notably elevated cholesterol levels, but also kidney cancer, testicular cancer, thyroid disease and gestational hypertension.

To date, several techniques have been employed to remove PFAS compounds from the environment and from drinking water. Such techniques include Granular Activated Carbon (GAC), ion exchange resins, and reverse osmosis. GAC has become the leading solution, but there is a continuing need for performance improvements in order for GAC to more effectively remove PFAS compounds from the environment and from drinking water.

Disclosure of Invention

The present disclosure describes sorbent materials with improved performance in removing PFAS from liquids and gases, including but not limited to PFOA, PFOS, and similar compounds. The disclosed embodiments include:

in one embodiment, a method for removing perfluoroalkyl and polyfluoroalkyl materials (PFAS) from a liquid or gas comprises providing a first sorbent material comprising from about 0.5% to about 25% by weight of an ion, salt, oxide, hydroxide, or carbonate of magnesium, calcium, strontium, barium, or combinations or compounds thereof, thereby increasing the sorption capacity of the sorbent material for perfluoroalkyl and polyfluoroalkyl materials (PFAS) relative to a sorbent material that does not comprise the ion, salt, oxide, hydroxide, or carbonate; and contacting the first sorbent material with a liquid or gas comprising PFAS.

In another embodiment, the first sorbent material comprises one or more of carbonaceous carbon, activated carbon, reactivated carbon, and carbon black.

In another embodiment, the carbonaceous carbon, activated carbon, reactivated carbon, or carbon black is formed from at least one of bituminous coal, subbituminous coal, lignite, anthracite, wood chips, sawdust, peat, nut shells, fruit pits, coconut shells, babassu nuts, macadamia nuts, african oil palm nuts (dende nut), peach pits, cherry pits, olive pits, walnut shells, wood, lignin, polymers, nitrogen-containing polymers, resins, petroleum pitch, bagasse, rice hulls, corn husks, wheat hulls, and grain hulls, graphene, carbon nanotubes, or polymer fibers.

In another embodiment, wherein said first sorbent material is a reactivated carbon.

In another embodiment, the first sorbent material is reagglomerated activated carbon.

In another embodiment, the further step involves providing a second sorbent material comprising one or more of carbonaceous carbon, activated carbon, reactivated carbon, carbon black, natural zeolite, synthetic zeolite, silica gel, alumina clay, zirconia, diatomaceous earth, and metal oxide and contacting the second sorbent material with a liquid or gas containing PFAS.

In another embodiment, the first sorbent material comprises one or more of magnesium oxide, calcium oxide, strontium oxide, or barium oxide.

In another embodiment, the first sorbent material comprises one or more of MgO or CaO.

In another embodiment, the ions, salts, oxides, hydroxides, or carbonates of the first sorbent material are introduced into the first sorbent material by one or more of dry mixing, wet impregnation, chemical vapor deposition, or physical vapor deposition.

In another embodiment, the first sorbent material comprises from about 1% to about 20% by weight of an ion, salt, oxide, hydroxide, or carbonate of magnesium, calcium, strontium, barium, or a combination or compound thereof.

In another embodiment, the first sorbent material comprises from about 2% to about 8% by weight of an ion, salt, oxide, or carbonate of magnesium, calcium, strontium, barium, or a combination or compound thereof.

In another embodiment, the first sorbent material is a reactivated carbon comprising ions, oxides, or carbonates of calcium, magnesium, sodium, potassium, and zinc, and which has not been subjected to any process to remove or reduce the amount of ions, oxides, or carbonates of calcium, magnesium, sodium, potassium, and zinc.

In another embodiment, the reactivated carbon is not subjected to any acid wash that removes or reduces the amount of ions, oxides or carbonates of calcium, magnesium, sodium and zinc.

Drawings

The aspects, features, benefits and advantages of the embodiments described herein will become apparent with reference to the following description, appended claims and accompanying drawings, in which:

fig. 1 is a graphical representation of the results of a rapid small-scale column test for activated carbon and reactivated carbon with elevated calcium content.

Fig. 2 is a graphical representation of more results of rapid small-scale column testing of activated carbon and reactivated carbon with elevated calcium content.

Fig. 3 is a graphical representation comparing the results of testing activated carbon, reactivated carbon with elevated calcium content, and activated carbon with elevated magnesium content.

Fig. 4 is a graphical representation of the results of testing activated carbon and reactivated carbon with elevated calcium content.

Fig. 5 is a graphical representation of further results of testing activated carbon and reactivated carbon with elevated calcium content.

Fig. 6 is a graphical representation of further results of testing activated carbon and reactivated carbon with elevated calcium content.

Fig. 7 is a graphical representation of the results of testing raw coal-based activated carbon, acid-washed reactivated carbon with elevated calcium content, reactivated carbon with high calcium content, activated carbon with high magnesium content, and activated carbon with pulverized magnesium oxide content.

Detailed Description

The present disclosure is not limited to the particular systems, devices, and methods described, as these may vary. The terminology used in the description is for the purpose of describing the particular versions or embodiments only and is not intended to limit the scope.

As used in this document, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. Nothing in this disclosure is to be construed as an admission that the embodiments described in this disclosure are not entitled to antedate such disclosure by virtue of prior invention. As used in this document, the term "comprising" means "including but not limited to".

As used herein, the term "about" means plus or minus 10% of the numerical value of the number used therewith. Thus, about 50% means in the range of 45% -55%.

As used herein, the term "sorbent material" is intended to encompass all known materials from any source that are capable of absorbing or adsorbing liquids and/or gases. For example, sorbent materials include, but are not limited to, activated carbon, reactivated carbon, natural and synthetic zeolites, silica gel, alumina, zirconia, and diatomaceous earth.

As used herein, the term "perfluoroalkyl and polyfluoroalkyl material (PFAS)" means any perfluoroalkyl or polyfluoroalkyl material, mixture of such materials, or derivative of one or more such materials. Examples of PFAS include perfluoroalkylsulfonate, perfluoroalkanesulfonic acid (PFSA), N-butylperfluoroalkanesulfonamide (BuFASA), N-butylperfluoroalkanesulfonamidoethanol (BuFASE), N-butylperfluoroalkanesulfonamidoacetic acid (BuFASAA), N-ethylperfluoroalkanesulfonamidoethanol (EtFASA), N-ethylperfluoroalkanesulfonamidoethanol (EtFASE), N-ethylperfluoroalkanesulfonamidoacetic acid (EtFASAA), perfluoroalkanesulfonamidoethanol (FASA), perfluoroalkanesulfonamidoethanol (FASE), perfluoroalkanesulfonamidoacetic acid (FASAA), N-methylperfluoroalkanesulfonamidoethanol (MeFASA), N-methylperfluoroalkanesulfonamidoacetic acid (MeAA FASE), N-methylperfluoroalkanesulfonamidoethanol (MeFASE), N-methylperfluorooctane sulfonamide (MeFOSA), Perfluoroalkanesulfonyl fluoride (PASF), 4, 8-dioxa-3H-perfluorononanoate, Ammonium Perfluorooctanoate (APFO), Fluoroprotein (FP), fluorotelomer carboxylic acid (FTCA), fluorotelomer alcohol (FTOH), fluorotelomer sulfonate (FTS), fluorotelomer sulfonic acid (FTSA), perfluoroalkylalkyl acid (PFAA), Perfluoroalkylsulfonamidoethanol (PFOSE), and any derivative thereof. These include, for example, but are not limited to, perfluorooctanoic acid (PFOA), perfluorooctanesulfonate, perfluorooctanesulfonic acid (PFOS), 2,3,3,3, -tetrafluoro-2- (heptafluoropropoxy) propionate, 2,3, 3-tetrafluoro-2- (heptafluoropropoxy) ammonium propionate, 1,2,2, 2-tetrafluoroethyl ether, 4: 2-fluorotelomer sulfonic acid (4:2FtS), 6: 2-fluorotelomer sulfonic acid (6:2FtS), 8: 2-fluorotelomer sulfonic acid (8:2FtS), perfluorobutyric acid (PFBA), perfluorobutane sulfonate, perfluorobutane sulfonic acid (PFBS), perfluorohexane sulfonate, perfluorohexane sulfonic acid (PFHxS), perfluorohexanoate, perfluorohexanoic acid (PFHxA), 4, 8-dioxa-3H-perfluorononanoate, Ammonium Perfluorooctanoate (APFO), N-ethylperfluorooctane sulfonamide (EtFOSA), N-ethylperfluorooctane sulfonamidoethanol (EtFOSE), perfluorooctane sulfonamide (PFOSA), perfluorooctane sulfonamidoacetic acid (FOSAA), perfluorooctane sulfonamidoethanol (FOSE), perfluorobutanoic acid, perfluoroalkyl carboxylate, perfluoroalkyl carboxylic acid (PFCA), perfluorodecanoic acid salt, perfluorodecanoic acid (PFDA), perfluorododecanoic acid salt, perfluorododecanoic acid (PFDoA), perfluorododecanesulfonic acid salt (PFDoS), perfluorododecanesulfonic acid (PFDoSA), perfluorodecane sulfonate, perfluorodecane sulfonic acid (PFDS), perfluoroheptanoic acid salt, perfluoroheptanoic acid (PFpA), perfluoroheptane sulfonate, perfluoroheptane sulfonic acid (PFHpS), perfluorononanoic acid salt, perfluorononane sulfonate, perfluorononane sulfonic acid (PFNS), perfluorooctanoic acid salt, perfluoroheptanoic acid (PFPA), perfluoroheptane sulfonate, perfluoroheptane sulfonic acid (PFNS), perfluorononane sulfonate, perfluorononane sulfonic acid salt, perfluorooctanoic acid salt, perfluorodecanoic acid (PFNA), perfluorodecanoic acid salt, perfluorodecanoic acid, Perfluorophosphonic Acid (PFPA), perfluorovaleric acid salts, perfluorovaleric acid (PFPeA), perfluoropentane sulfonate, perfluoropentane sulfonic acid (PFPeS), perfluorophosphinic acid (PFPiA), perfluorotetradecanoic acid (PFTeDA), perfluorotridecanoic acid (PFTrDA), perfluoroundecanoate, perfluoroundecanoic acid (PFUnA), perfluoroundecanesulfonate (PFUnS), perfluoroundecanesulfonic acid (PFUnS), or Polytetrafluoroethylene (PTFE).

Sorbent material

The present disclosure provides a variety of sorbent materials including, but not limited to, carbonaceous carbons, activated carbons, reactivated carbons, carbon blacks, natural and synthetic zeolites, silicas, silica gels, aluminas, alumina clays, zirconia, diatomaceous earths, or metal oxides. Sorbent materials may be used alone or in combination. In some embodiments where sorbent materials are used in combination, multiple treated sorbents are mixed together; such treated sorbents may be the same or different. In other embodiments, a sorbent material treated as described herein is combined with an untreated sorbent material. For example, in one embodiment, a first sorbent material treated according to the present disclosure and being one or more of carbonaceous carbon, activated carbon, reactivated carbon, or carbon black is mixed with a second sorbent that is not treated according to the present disclosure and is one or more of carbonaceous carbon, activated carbon, reactivated carbon, carbon black, natural and synthetic zeolites, silica gel, alumina clay, zirconia, diatomaceous earth, or metal oxides.

In some embodiments, the sorbent material is activated carbon or reactivated carbon. In such embodiments, the activated carbon or reactivated carbon is prepared from any precursor carbonaceous material known in the art, including, but not limited to, bituminous coal, sub-bituminous coal, lignite, anthracite, wood chips, sawdust, peat, nut shells, fruit pits, coconut shells, babassu nuts, macadamia nuts, african oil palm nuts, peach pits, cherry pits, olive pits, walnut shells, wood, lignin, polymers, nitrogenous polymers, resins, petroleum pitch, bagasse, rice hulls, corn husks, wheat hulls and grain hulls, graphene, carbon nanotubes, polymer fibers, and any other carbonaceous material or combination thereof. In some embodiments, the carbonaceous material may be derived from activated carbon produced from various precursors that have been in use and subsequently reactivated and/or regenerated. In some embodiments, the sorbent material feedstock is provided in a pre-oxidized state. In other embodiments, the sorbent material feedstock is provided in an unoxidized state.

When the sorbent material is activated or reactivated carbon, it is of various grades and types selected based on performance requirements, cost, and other considerations. In some embodiments, the sorbent material is activated carbon or reactivated carbon in powdered form. In other embodiments, the sorbent material is activated carbon or reactivated carbon in particulate form, wherein such particulate activated carbon or reactivated carbon is formed by pulverizing a precursor carbonaceous material, forming the resulting pulverized material into agglomerates, and then pulverizing the agglomerates to the desired size. The resulting granular material is then heated to perform various operations including removing volatile compounds and activating the precursor carbonaceous material contained therein. In still other embodiments, the sorbent material is activated carbon or reactivated carbon in the form of pellets. In such embodiments, the sorbent material is formed by pulverizing a precursor carbonaceous material, extruding the pulverized material into pellets along with a binder material. The pellets are then heated to perform various operations including removing volatile compounds and activating the precursor carbonaceous material contained therein.

Sorbent materials made from activated carbon and/or reactivated carbon are formed by any useful process. In some embodiments, the activated carbon and/or reactivated carbon is formed by carbonization, activation, and/or reactivation. In some embodiments, the activated carbon and/or reactivated carbon is formed by oxidizing and devolatilizing carbonaceous material, wherein steam and/or carbon dioxide is vaporized to form a pore structure in the activated carbon or reactivated carbon that imparts sorbent material properties to the activated carbon or reactivated carbon. The initial oxidation and devolatilization process may include chemical treatment with dehydration chemicals such as phosphoric acid, sulfuric acid, sodium hydroxide, potassium hydroxide, and combinations of these.

In some embodiments, the activated carbon is Granular Activated Carbon (GAC), which is defined as activated carbon particles having a size that is retained on a 50 mesh screen (about 0.300mm holes). In other embodiments, the activated carbon is Powdered Activated Carbon (PAC), which is defined as particles that pass through an 80 mesh screen (about 0.180mm holes). While these particle size ranges are mentioned for activated carbon sorbent materials, it is also contemplated that any of the disclosed sorbent materials can be measured from the above 50 mesh and 80 mesh screen sizes.

In some embodiments, the sorbent material is a reactivated sorbent material that has previously depleted its sorption capacity and has been reactivated to restore at least some of the original sorption capacity. Any of the sorbent materials listed above may be reactivated after use, and reactivation may be by heat, pressure, chemical exposure, or combinations thereof. In some embodiments, the reactivated sorbent material is reactivated carbon. Reactivated carbon is produced by heating spent activated carbon in an oxygen-free furnace and using water vapor as the selective oxidant. During reactivation, the adsorbed and adsorbed organic compounds are vaporized or pyrolyzed from the activated carbon to form carbon char. In some embodiments, the heating is conducted above about 700 ℃, and the resulting reactivated carbon may thereafter be reused for various purposes, including water treatment. In some embodiments, the temperature of heating is about 500 ℃, about 550 ℃, about 600 ℃, about 650 ℃, about 700 ℃, about 750 ℃, about 800 ℃, about 850 ℃, about 900 ℃, about 950 ℃, about 1000 ℃, about 1050 ℃, about 1100 ℃, or any range consisting of any two or more points in the above list.

In some embodiments, the sorbent material is deployed in an application exposed to water comprising a mineral content. In some embodiments, the mineral content comprises calcium carbonate that accumulates on the sorbent material during use of the sorbent material in filtering water. In such an embodimentIn embodiments, reactivation of the spent sorbent material results in the following reaction: CaCO₃(s)→CaO(s)+CO₂(g) In that respect As will be seen in the examples, this regeneration technique results in a reactivated sorbent material with improved sorption performance for PFAS compounds, including PFOA and PFOS compounds. The same performance improvements are expected to apply not only to PFAS compounds but also to other chemically similar or chemically related compounds.

In some embodiments, the sorbent material is treated with an ion, salt, oxide, hydroxide, or carbonate of an alkaline earth metal of group 2 of the International Union of Pure and Applied Chemistry (IUPAC). Of these compounds, Mg, Ca, Sr, Ba, and combinations thereof are expected to be useful. Exemplary oxides include MgO, CaO, SrO, BaO, and combinations thereof. The combination may be a mixture of the above listed ions, salts, oxides, hydroxides or carbonates or a chemical combination of the above listed ions, oxides, hydroxides or carbonates in any stoichiometric relationship. Each of the above compounds may be used alone or in combination, and they may also be used in any possible stoichiometric relationship. Combinations of one or more ions, oxides, hydroxides, and carbonates of IUPAC group 2 are also contemplated. The combination may be a mixture or stoichiometric or metal doped in the oxide used to treat the activated carbon. Treatment of the sorbent material with the one or more treatment materials may be achieved by any suitable method, including dry mixing, wet impregnation, chemical vapor deposition, physical vapor deposition, or combinations thereof. Further, the same or different processes may be used to deposit more than one material on the sorbent material. The treatment can also be accomplished as a byproduct of the use of the sorbent material without the need for a separate treatment step. For example, in some embodiments, sorbent materials used in service become loaded with minerals naturally present in water, including ions, oxides, and carbonates of calcium, magnesium, sodium, potassium, magnesium, and zinc. Examples of such minerals include, but are not limited to, calcium ions, calcium oxides and hydroxides, calcium carbonate (CaCO)₃) Magnesium ions, magnesium oxides and hydroxidesMagnesium carbonate (MgCO)₃) Sodium ions, sodium oxides and hydroxides, sodium carbonate (Na)₂CO₃) Potassium ions, potassium oxides and hydroxides, potassium carbonate (K)₂CO₃) Zinc ions, zinc oxides and hydroxides, zinc carbonate (ZnCO)₃) And combinations of the foregoing. The treatment is expected to improve the sorption performance of the sorbent material. The same performance improvements are expected to apply to PFAS compounds, including PFOA and PFOS, as well as other chemically similar or chemically related compounds.

The amounts of the above-mentioned ions, oxides, hydroxides, carbonates or combinations of these materials are measured in weight relative to the total weight of the sorbent material being treated and the ions, oxides, hydroxides, carbonates or combinations of these materials. The amount of ions, salts, oxides, hydroxides, or carbonates is not limited, and in some embodiments is less than about 25 wt.%, less than about 20 wt.%, less than about 15 wt.%, less than about 10 wt.%, less than about 8 wt.%, less than about 6 wt.%, less than about 4 wt.%, less than about 2 wt.%, less than about 1 wt.%, less than about 0.9 wt.%, less than about 0.8 wt.%, less than about 0.7 wt.%, less than about 0.6 wt.%, less than about 0.5 wt.%, less than about 0.4 wt.%, less than about 0.3 wt.%, less than about 0.2 wt.%, or less than about 0.1 wt.%. In some embodiments, the amount of ion, salt, oxide, hydroxide, or carbonate is about 25 wt%, about 20 wt%, about 15 wt%, about 10 wt%, about 9 wt%, about 8 wt%, about 7 wt%, about 6 wt%, about 5 wt%, about 4 wt%, about 3 wt%, about 2 wt%, about 1 wt%, about 0.9 wt%, about 0.8 wt%, about 0.7 wt%, about 0.6 wt%, about 0.5 wt%, about 0.4 wt%, about 0.3 wt%, about 0.2 wt%, about 0.1 wt%, or any range formed by any two endpoints described above. In some embodiments, the amount of ion, salt, oxide, hydroxide, or carbonate is from about 1 wt% to about 10 wt%, from about 2 wt% to about 10 wt%, from about 4 wt% to about 10 wt%, from about 6 wt% to about 10 wt%, from about 1 wt% to about 8 wt%, from about 2 wt% to about 8 wt%, from about 4 wt% to about 6 wt%, or from about 6 wt% to about 8 wt%.

Sorbent materials can be formed by various techniques. In one embodiment, the sorbent material comprises activated carbon that is reagglomerated activated carbon. In reagglomerating activated carbon, a precursor carbonaceous material, typically coal, is pulverized into a powder. The powder is then mixed with a binder. The mixture of powder and binder is then re-agglomerated into a briquette. The agglomerates were then crushed and sized. The now crushed and sized agglomerates are carbonized to harden the binder and finally the crushed, sized and carbonized agglomerate material is thermally activated. This process forms granular activated carbon. During this process, one or more ions, salts, oxides, hydroxides, or carbonates of IUPAC group 2 elements may be added, including Mg, Ca, Sr, Ba, and combinations. In one embodiment, a powder of ions, salts, oxides, hydroxides or carbonates is mixed with the pulverized coal prior to mixing with the binder. In another embodiment, a liquid solution of ions, salts, oxides, hydroxides or carbonates is applied to the crushed and sized agglomerates prior to the carbonization step. In another embodiment, a liquid solution of ions, salts, oxides, hydroxides or carbonates is mixed after the carbonization step but before the activation step.

In some embodiments, the sorbent material is formed from a precursor that is used activated carbon that was previously used for water filtration and reactivated. In particular, used activated carbon that has been used in point-of-use filters, point-of-entry filters, portable filters, and municipal drinking water filtration often contains a large amount of inorganic minerals that reside on the surface of the activated carbon material. In other embodiments, the precursor carbonaceous material is used activated carbon that has not been previously used for water filtration but is used for other applications. Other applications include food processing, beverage processing, sugar refining, wastewater treatment, waste gas treatment, tank cleaning, tank degassing, and combinations thereof. In some embodiments, the used activated carbon previously used for water filtration contains one or more inorganic materials present in groundwater, including ions, oxides, and carbonates of calcium, magnesium, sodium, potassium, and zinc.

In some embodiments, the sorbent material formed from a precursor that is used activated carbon is not treated to remove any inorganic material present in the groundwater. This means that the sorbent material will comprise ions, oxides and carbonates of calcium, magnesium, sodium, potassium and zinc. In still other embodiments, the sorbent material formed from a precursor that is used activated carbon is not treated by acid washing to remove any inorganic materials present in the groundwater. In such embodiments, one or more ions, salts, oxides, hydroxides or carbonates present in the groundwater have been slowly impregnated onto the surface of the spent activated carbon and retained during reactivation to form the sorbent material.

Use of

The sorbent materials of the present disclosure are useful whenever it is necessary to remove PFAS, PFOA, PFOS or chemically similar or chemically related compounds from liquids and/or gases (including water). The removal may be for human or animal consumption purposes, or for environmental remediation purposes. Specific applications include point-of-use filters, point-of-entry filters, portable filters, municipal drinking water filtration, municipal waste filtration, and industrial waste filtration. In some embodiments, the sorbent material of the present disclosure is used alone without any other sorbent material. In some embodiments, the sorbent materials of the present disclosure are used in combination with other sorbent materials.

Although the sorbent materials of the present disclosure are disclosed primarily as removing PFAS, PFOA, PFOS, or chemically similar or chemically related compounds, the use of the sorbent materials is not so limited. In still other embodiments, the sorbent material is adapted to remove any compounds and/or by-products that cause taste and odor problems in the water. Throughout this application, such compounds are referred to as "taste and odor compounds". Examples of such taste and odor compounds include one or more of trans-1, 10-dimethyl-trans-9-decalin ("Geosmin"), 2-Methylisoborneol (MIB), Isopropylmethoxypyrazine (IPMP), Isobutylmethoxypyrazine (IBMP), methyl tert-butyl ether (MTBE), 2, 4-heptadienal, decadienal, octanal, chlorine, chloramine, chlorophenol, iodoform, hydrocarbons, Volatile Organic Compounds (VOCs), iron oxides, copper oxides, zinc oxides, manganese, and manganese oxides.

In some embodiments, the sorbent material is disposed within the container. The container contains a sorbent material and allows a liquid or gas to flow over or through the container, thereby contacting the liquid or gas with the sorbent material. In some embodiments, the vessel is a permanent vessel that is installed within an equipment or process facility and connected by piping or other fluid conduits such that a liquid or gas flows through the vessel. The used sorbent material is emptied from the vessel and replaced with virgin sorbent material or reactivated sorbent material or both from time to ensure that the sorbent material remains effective after removal of PFAS, PFOA, PFOS or chemically similar or chemically related compounds from the liquid or gas flowing through the vessel. The physical form of the sorbent material within the container is not limited and the sorbent material may be provided loose (separately) or formed into a cartridge with other structural materials holding it in place or having other structural materials mixed as a binder.

In some embodiments, the vessel itself is designed to be quickly replaced and to minimize changes to external components such as pumps and conduits that deliver liquids or gases to the vessel. In such embodiments, the container is referred to as a "cartridge" and it can be connected and disconnected from the surrounding components. In some embodiments, the cartridge is disposable, such as in consumer drinking water applications. In other embodiments, the cartridge is intended to be refurbished, wherein the cartridge containing spent sorbent is returned for cleaning or reactivation of the sorbent material, refilled with fresh virgin or reactivated sorbent material, and returned to service after the refurbishment operation is complete.

The sorbent materials described above may be used alone or in combination with other materials. In some embodiments, a composition in which the sorbent material is combined with a binder is formed and molded, extruded, or otherwise formed into a shape or pellet. The binder is not limited and includes inorganic binders and organic binders. As examples of inorganic binders, metals, ceramics, clays, glasses or combinations of one or more of the foregoing are commonly used. As examples of organic binders, petroleum resins and/or asphalts, natural resins and/or asphalts, polymers or combinations of one or more of the above are used.

Example (b):

while several experimental examples are contemplated, these examples are intended to be non-limiting.

Example 1

Columns of Granular Activated Carbon (GAC) were constructed to test the adsorption of PFAS compounds. The depleted FILTRASORB 400(F400) feedstock previously used to filter municipal drinking water is first provided. Such materials are available from Calgon Carbon Corp. (moons, pa). FILTASORB F400 is a coal-based granular activated carbon having a maximum moisture content of 2 weight percent, an effective size of about 0.55mm to about 0.75mm, and an apparent density of about 0.54g/cm³. The spent F400 is reactivated in a rotary kiln with water vapor at elevated temperature to restore its surface activity and decompose any organic compounds.

The now reactivated F400 is referred to as F400 CMR (custom Multinicral React). The reactivated F400 CMR is similar to the virgin F400 material, but because the reactivated F400 CMR was previously used to treat groundwater with elevated calcium levels, the reactivated F400 CMR has a higher calcium content than the virgin F400 activated carbon. In example 1, the calcium content of the F400 CMR was about 0.36 wt% and the calcium content of the native F400 was 0.05 wt%.

Reference is now made to figure 1 which shows the results of the PFAS Rapid Small Scale Column Test (RSSCT) using the PFOA penetration curve. The testing was performed according to ASTM D6586-03(2014), but scaled down to a column diameter of 0.62 cm. The entry concentration was about 0.9. mu.g/L PFOA and about 1.7. mu.g/L total PFAS and the data were recorded to generate a breakthrough curve. Breakthrough was measured as μ g/L concentration that penetrated the column of native F400 or F400 CMR. Also shown in FIG. 1 is the EPA health guideline limit of 70 parts per trillion, which corresponds to a penetration concentration of 0.07 μ g/L. The amounts plotted are the amount of PFOA in water.

As shown in figure 1, the virgin F400 carbon begins to show an elevated concentration as about 10,000 bed volumes of water pass through the carbon in the bed, indicating the presence of initial breakthrough of the PFOA. In contrast, figure 1 shows the penetration of the F400 CMR against PFOA until at least about 20,000 bed volumes of water pass through the carbon in the bed. The greater breakthrough bed water equivalent indicates that a filter constructed using a bed of F400 CMR activated carbon can absorb and adsorb a greater amount of the detrimental PFAS compound than the same filter constructed with virgin F400 activated carbon.

Example 2

Columns of GAC were constructed and tested using the same procedure as in example 1 above, using the same virgin F400 activated carbon and F400 CMR reactivated carbon with elevated calcium levels as in example 1. The resulting column was tested with an inlet concentration of about 230ng/L PFOA concentration in water-about 230 nanograms per liter of PFOA. The total concentration of Perfluorochemicals (PFCs) in the inlet water was about 1.2 μ g/L, which included PFOA at the concentrations described above.

The results of example 2 are shown in figure 2. In fig. 2, the breakthrough, expressed as bed volume equivalent, again shows the durability of the GAC column. Virgin F400 began to show signs of breakthrough at about 70,000 bed volumes, while reactivated F400 CMR showed signs of breakthrough only at about 95,000 bed volumes.

Example 3

MgO agglomerated carbon is prepared. MgO agglomerated carbon is manufactured from reagglomerated metallurgical grade bituminous coal. During the reagglomeration process, the pulverized coal is impregnated with magnesium oxide added in the dry state.

Additional CMR reactivated carbons were also prepared and are referred to as "CMR high Ca. The CMR high Ca reactivated carbon is similar to the virgin F400 carbon and the CMR reactivated carbon previously described, except that the CMR high Ca has an increased calcium content. The CMR high Ca reactivated carbon tested had a calcium content of about 2 wt%, compared to a CMR with a calcium content of about 0.36 wt% and a virgin F400 carbon with a calcium content of 0.05 wt%.

The above F400, MgO agglomerated and F400 high Ca were tested to determine the simulated days of operation. In these tests, the entry concentration of PFOA + PFOS was 345ng/L, that of PFOA was 185ng/L, and that of PFOS was 160 ng/L. The bed volumes were tested until exhibiting a breakthrough concentration of 70ppt PFOA, PFOS or both PFOA and PFOS (as PFOA + PFOS). The results of these tests are described in table 1 below:

TABLE 1

The same three activated carbons in table 1 were also tested for specification characteristics. The test includes results of apparent density of carbon when measured using ASTM2854-09 (2014). The results of this test are provided in table 2 below:

TABLE 2

The test results demonstrate that treatment of activated carbon with various components has a significant effect on the performance of activated carbon as a sorbent for PFOA, PFOS and/or a combination of these two compounds found in drinking water applications.

Example 4

Columns of GAC were constructed and tested using the same F400 and CMR F400 discussed above, using the same procedure as in example 1 above. The results of example 4 are shown in fig. 4-6. Figure 4 shows the results of adsorption of different PFOA compounds. PFOA efflux concentration breakthrough, expressed as bed volume equivalent, shows the durability of the GAC column. The column was tested with an inlet concentration of about 153ng/L PFOA concentration in water-about 153 nanograms per liter PFOA.

FIG. 5 shows the results of adsorption of a 4:2FtS (6: 2-fluorotelomeric sulfonic acid) compound. The 4:2FtS effluent concentration breakthrough, expressed as bed volume equivalent, shows the durability of the GAC column. The column was tested with an inlet concentration of about 130 ng/L4: 2FtS in water-about 130 nanograms per liter 4:2 FtS.

Figure 6 shows the results of the adsorption of PFOS compounds. PFOS efflux concentration breakthrough, expressed as bed volume equivalent, shows the durability of the GAC column. The column was tested with an inlet concentration of about 177ng/L PFOS concentration in water-about 177 nanograms per liter PFOS.

Example 5

CMR reactivated carbon was prepared and referred to as "acid-washed CMR 0.65% Ca. Acid-washed CMR 0.65% Ca reactivated carbon is the same as the CMR high Ca described above, except that it is acid-washed and has a reduced Ca content. The CMR high Ca (also referred to as "CMR 2 wt% Ca") tested had a Ca content of about 2 wt%. The acid-washed CMR 0.65% Ca tested had a Ca content of about 0.65 wt%.

Two additional GAC samples were prepared and designated "AdMix MgO 4.8% for Mg" and "AdMix MgO 12% for Mg". These samples were obtained by adding powdered MgO to activated CAL12X40 gac (calgon Carbon corporation), which is activated Carbon from coal-based reagglomerated pitch virgin Carbon. Specifically, AdMix MgO 4.8% was prepared for Mg by adding 8% powdered MgO to CAL12X40, and AdMix MgO 12% was prepared for Mg by adding 20% powdered MgO to CAL12X 40. The resulting AdMix MgO 4.8% for Mg and AdMix MgO 12% for Mg samples tested had divalent cation contents of about 4.8% and about 12%, respectively.

The MgO agglomerated sorbent discussed above was tested and had a divalent cation content of about 4%. MgO agglomeration is different from Admix MgO 4.8% for Mg and Admix MgO 12% for Mg because MgO in MgO agglomeration is added prior to carbonization and carbon activation.

Columns of GAC were constructed and tested using CAL-virgin carbon (CAL12X40), acid-washed CMR 0.65% Ca, CMR high Ca (about 2 wt% Ca), agglomerated MgO, AdMix MgO 4.8% for Mg and AdMix MgO 12% for Mg using the same procedure as in example 1 above.

GAC was also tested for specification characteristics. The test includes results of the percentage of divalent cations measured using proton induced X-ray emission (PIXE). The test also includes results of apparent density of carbon when measured using ASTM2854-09 (2014). The results of this test are provided in table 3 below:

TABLE 3

The results of example 5 are shown in fig. 7. Figure 7 shows the results of the adsorption of the PFOA compound. PFOA efflux concentration breakthrough, expressed as bed volume equivalent, shows the durability of the GAC column. The column was tested with an inlet concentration of about 61ng/L PFOA concentration in water-about 61 nanograms per liter of PFOA. Acid-washed CMR 0.65% Ca first began showing signs of breakthrough, followed by CAL-virgin carbon, CMR 2 wt.% Ca, agglomerated MgO, AdMix MgO 4.8% for Mg and AdMix MgO 12% for Mg.

The present disclosure is not limited to the particular embodiments described in this application, which are intended as illustrations of various aspects. It will be apparent to those skilled in the art that many modifications and variations can be made without departing from the spirit and scope thereof. Functionally equivalent methods and devices within the scope of the present disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing description. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It should also be understood that this disclosure is not limited to particular compositions, methods, devices, and articles, as these may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. Various singular/plural permutations may be expressly set forth herein for the sake of clarity.

It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). While the various compositions, methods, and devices are described as "comprising" various components or steps (interpreted to mean "including, but not limited to"), the compositions, methods, and devices can also "consist essentially of" or "consist of" the various components and steps, and such terms should be interpreted as defining a substantially closed member group. It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present.

For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to embodiments containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations.

In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, means at least two recitations, or two or more recitations). Further, in those instances where a convention analogous to "at least one of A, B and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B and C" would include but not be limited to systems that have a alone, B alone, C alone, a and B together, a and C together, B and C together, and/or A, B and C together, etc.). In those instances where a convention analogous to "A, B or at least one of C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B or C" would include but not be limited to systems that have a alone, B alone, C alone, a and B together, a and C together, B and C together, and/or A, B and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or expression that sets forth two or more alternative terms, whether in the description, claims, or drawings, should be understood to encompass the possibility of including one of those terms, including either or both of those terms. For example, the expression "a or B" is to be understood as including the possibility of "a" or "B" or "a and B".

In addition, while features or aspects of the present disclosure are described in terms of Markush groups (Markush groups), those skilled in the art will recognize that the present disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

As will be understood by those skilled in the art, for any and all purposes, such as in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges thereof. Any listed range can be easily identified as being fully descriptive and allowing the same range to be broken down into at least equal halves, thirds, quarters, fifths, tenths, etc. By way of non-limiting example, each range discussed herein can be readily broken down into a lower third, a middle third, an upper third, and the like. As will also be understood by those of skill in the art, all languages such as "at most," "at least," and the like include the recited numbers and refer to ranges that may be subsequently broken down into sub-ranges as discussed above. Finally, as will be understood by those of skill in the art, a range includes each individual member. Thus, for example, a group having 1-3 cells refers to a group having 1,2, or 3 cells. Similarly, a group having 1-5 cells refers to groups having 1,2, 3, 4, or 5 cells, and so on.

Various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art, each of which is also intended to be encompassed by the disclosed embodiments.