# US 10,441,940 B2 · Polymers grafted with organic phosphorous compounds for extracting uranium from solutions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,441,940 B2 - Document ID: US10441940B2 - Status: Granted - Kind: B2 - Application number: 14/412,892 - Filed: 2013-08-20 - Published: 2015-07-09 - Granted: 2019-10-15 - Earliest claimed: 2012-08-20 - Assignees: University of Maryland, College Park; The Catholic University of America - Applicants: University of Maryland; The Catholic University of America - Inventors: Chanel Tissot; Aaron Barkatt; Mohamad I. Al-Sheikhly - Web page: https://patentgrep.com/patent/US10441940B2 ## CPC - B01J 20/3085: {Chemical treatments not covered by groups B01J20/3007 - B01J20/3078} - B01J 20/264: {derived from different types of monomers, e.g. linear or branched copolymers, block copolymers, graft copolymers} - B01J 20/265: {modified or post-treated polymers (polymer carriers or substrates subjected to further impregnating or coating B01J20/3208)} - B01J 20/28023: {Fibres or filaments (fibres or filaments in the form of membranes B01J20/28038; B01J20/28007 takes precedence)} - B01J 20/28038: {Membranes or mats made from fibers or filaments} - B01J 20/2804: {Sheets with a specific shape, e.g. corrugated, folded, pleated, helical} - B01J 20/321: {consisting of a polymer obtained by reactions involving only carbon to carbon unsaturated bonds} - B01J 20/3212: {consisting of a polymer obtained by reactions otherwise than involving only carbon to carbon unsaturated bonds} - B01J 20/3278: {Polymers being grafted on the carrier} - B01J 20/3425: {of sorbents or filter aids comprising organic materials} - B01J 20/3475: {in the liquid phase} - C02F 1/285: {using synthetic organic sorbents} - C08G 69/00: Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule (products obtained from isocyanates or isothiocyanates C08G18/00; polyamide-imides C08G73/14) - C22B 60/0265: {extraction by solid resins} - G21F 9/12: by absorption; by adsorption; by ion-exchange - C02F 1/683: {by addition of complex-forming compounds} - C02F 2101/006: {Radioactive compounds} - C02F 2103/08: Seawater, e.g. for desalination - C02F 2303/16: Regeneration of sorbents, filters - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - C02F: TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE (separation in general B01D; special arrangements on waterborne vessels of installations for treating water, waste water or sewage, e.g. for producing fresh water, B63J; adding materials to water to prevent corrosion C23F; treating radioactively-contaminated liquids G21F9/04; regeneration of reactants for recirculation into processes, see the relevant places for the processes) - C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS - C22B: PRODUCTION AND REFINING OF METALS (electrolytic C25); PRETREATMENT OF RAW MATERIALS - G21F: PROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR (radiation protection by pharmaceutical means A61K8/00, A61Q17/04; in cosmonautic vehicles B64G1/54; combined with a reactor G21C11/00; combined with X-ray tubes H01J35/16; combined with X-ray apparatus H05G1/02) ## Abstract Complexing or chelating agents that offer strong, selective bonding with uranium as well as a broad pH range of effectiveness, specifically including the pH range around 8.2, together with the acrylic double bonds required for radiation-induced grafting on polymers to remove uranium from a solution such as seawater. The novel adsorbing species are phosphorus-containing molecules, in particular organic phosphates, phosphonates and phosphoric acids. Organic phosphorus compounds, for example, organic phosphates, phosphonates, and phosphoric acids, are attached to polymer fibers to form fibers, fiber fabrics or membranes that are effective, or show activity, in uranium adsorption. ## Claims ### Claim 1 An adsorbent material prepared by a process of radiation grafting by using a source of ionizing radiation to graft bis(2-methacryloxyethyl) phosphate onto a polymeric fiber, while the polymeric fiber is immersed in an oxygen-free solution of the phosphate, wherein the polymeric fiber has a surface area of at least 10 m2/gram. ### Claim 2 (depends on 1) The adsorbent material according to claim 1, wherein the radiation grafting bis(2-methacryloxyethyl) phosphate onto a polymeric fiber having a surface area of at least 10 m2/gram is performed by radiation grafting bis(2-methacryloxyethyl) phosphate onto polycaproamide. ### Claim 3 (depends on 1) The adsorbent material according to claim 1, wherein the source of ionizing radiation is a gamma source providing a total radiation dose of 0.2-50 kGy to effect the grafting. ### Claim 4 (depends on 3) The adsorbent material according to claim 3, wherein the gamma source provides a total radiation dose of 1-10 kGy to effect the grafting. ### Claim 5 (depends on 1) The adsorbent material according to claim 1, wherein the polymeric fiber is irradiated while immersed in an oxygen-free solution containing components selected from the group consisting of surfactants, polar organic liquids, and combinations thereof. ### Claim 6 (depends on 1) The adsorbent material according to claim 1, wherein the radiation grafting is characterized by a degree of grafting, defined as the weight gain of the polymeric fiber upon grafting and drying relative to its original weight, that is between 25% and 250%. ### Claim 7 (depends on 6) The adsorbent material according to claim 6, wherein the degree of radiation grafting is between 50% and 200%. ### Claim 8 (depends on 7) The adsorbent material according to claim 7, wherein the degree of radiation grafting is between 80% and 150%. ### Claim 9 (depends on 1) The adsorbent material according to claim 1, wherein the polymer is sonicated following radiation grafting to remove homopolymerized material. ### Claim 10 An adsorbent material prepared by a process of radiation grafting by using a source of ionizing radiation to graft bis(2-methacryloxyethyl) phosphate onto a polymer while the polymer is immersed in an oxygen-free solution of the phosphate, wherein the adsorbent material, consisting of the grafted polymer, is contacted with the aqueous solution, wherein the aqueous solution includes uranium, and the adsorbent material removes an amount of uranium, at least 0.1%, relative to the dry weight of the polymer, from the aqueous solution. ### Claim 11 (depends on 10) The adsorbent material according to claim 10, wherein the adsorbent material is regenerated through desorption of the uranium using an aqueous solution to remove the uranium from the phosphate-grafted polymer. ### Claim 12 (depends on 11) The adsorbent material according to claim 11, wherein the adsorbent material is regenerated through desorption of the uranium using a near-neutral solution of a complexing reagent to remove the uranium from the phosphate-grafted polymer. ### Claim 13 (depends on 12) The adsorbent material according to claim 12, wherein the adsorbent material is regenerated through desorption of the uranium using a near-neutral solution of a complexing reagent that is an aqueous solution of ammonium oxalate to remove the uranium from the phosphate-grafted polymer. ### Claim 14 A method of removing uranium from an aqueous solution comprising the steps of: providing an adsorbent material produced by using a source of ionizing radiation to graft bis(2-methacryloxyethyl) phosphate onto a polymer; and contacting the grafted polymer with the aqueous solution that includes uranium such that the adsorbent material removes an amount of uranium, at least 0.1%, relative to the dry weight of the polymer, from the aqueous solution. ### Claim 15 (depends on 14) The method of removing uranium from an aqueous solution according to claim 14, wherein the radiation grafting of bis(2-methacryloxyethyl) phosphate onto the polymer is performed by radiation grafting bis(2-methacryloxyethyl) phosphate onto a polymeric fiber having a surface area of at least 10 m2/gram. ### Claim 16 (depends on 15) The method of removing uranium from an aqueous solution according to claim 15, wherein the radiation grafting bis(2-methacryloxyethyl) phosphate onto the polymeric fiber having a surface area of at least 10 m2/gram is performed by radiation grafting bis(2-methacryloxyethyl) phosphate onto polycaproamide. ### Claim 17 (depends on 14) The method of removing uranium from an aqueous solution according to claim 14, wherein the source of ionizing radiation is a gamma source providing a total radiation dose of 0.2-50 kGy to effect the radiation grafting. ### Claim 18 (depends on 17) The method of removing uranium from an aqueous solution according to claim 17, wherein the gamma source provides a total radiation dose of 1-10 kGy to effect the radiation grafting. ### Claim 19 (depends on 14) The method of removing uranium from an aqueous solution according to claim 14, wherein the step of contacting the grafted polymer with the aqueous solution includes contacting the grafted polymer with a solution containing components selected from the group consisting of surfactants, polar organic liquids, and combinations thereof. ### Claim 20 (depends on 14) The method of removing uranium from an aqueous solution according to claim 14, wherein the radiation grafting is characterized by a degree of grafting, defined as the weight gain of the polymer upon grafting and drying relative to its original weight, that is between 25% and 250%. ### Claim 21 (depends on 20) The method of removing uranium from an aqueous solution according to claim 20, wherein the degree of radiation grafting is between 50% and 200%. ### Claim 22 (depends on 21) The method of removing uranium from an aqueous solution according to claim 21, wherein the degree of radiation grafting is between 80% and 150%. ### Claim 23 (depends on 14) The method of removing uranium from an aqueous solution according to claim 14, wherein the polymer is sonicated following radiation grafting to remove homopolymerized material. ### Claim 24 (depends on 14) The method of removing uranium from an aqueous solution according to claim 14, wherein the adsorbent material is regenerated through desorption of the uranium using an aqueous solution to remove the uranium from the phosphate-grafted polymer. ### Claim 25 (depends on 24) The method of removing uranium from an aqueous solution according to claim 24, wherein the adsorbent material is regenerated through desorption of the uranium using a near-neutral solution of a complexing reagent to remove the uranium from the phosphate-grafted polymer. ### Claim 26 (depends on 25) The method of removing uranium from an aqueous solution according to claim 25, wherein the adsorbent material is regenerated through desorption of the uranium using a near-neutral solution of a complexing reagent that is an aqueous solution of ammonium oxalate to remove the uranium from the phosphate-grafted polymer. ### Claim 27 An adsorbent material for removing uranium from an aqueous solution wherein the adsorbent material is prepared by a process of radiation grafting by using a source of ionizing radiation to graft bis(2-methacryloxyethyl) phosphate onto a polymer, while the polymer is immersed in an oxygen-free solution of the organic phosphate; contacting the grafted polymer with the aqueous solution that includes uranium such that the adsorbent material removes an amount of uranium, at least 0.1%, relative to the dry weight of the polymer, from the aqueous solution; and regenerating the adsorbent material at least once through desorption of the uranium using a near-neutral solution of a complexing reagent that is an aqueous solution of ammonium oxalate to remove the uranium from the phosphate-grafted polymer. ### Claim 28 (depends on 27) The adsorbent material according to claim 27, wherein the adsorbent material for removing uranium from an aqueous solution is an adsorbent material for removing uranium from an aqueous solution of one of brine or seawater. ### Claim 29 (depends on 27) The adsorbent material according to claim 27, wherein the radiation grafting of bis(2-methacryloxyethyl) phosphate onto the polymer is performed by radiation grafting bis(2-methacryloxyethyl) phosphate onto a polymeric fiber having a surface area of at least 10 m2/gram. ### Claim 30 (depends on 29) The adsorbent material according to claim 29, wherein the radiation grafting bis(2-methacryloxyethyl) phosphate onto a polymeric fiber having a surface area of at least 10 m2/gram is performed by radiation grafting bis(2-methacryloxyethyl) phosphate onto polycaproamide. ### Claim 31 (depends on 27) The adsorbent material according to claim 27, wherein the source of ionizing radiation is a gamma source providing a total radiation dose of 0.2-50 kGy to effect the grafting. ### Claim 32 (depends on 31) The adsorbent material according to claim 31, wherein the gamma source provides a total radiation dose of 1-10 kGy to effect the grafting. ### Claim 33 (depends on 27) The adsorbent material according to claim 27, wherein the radiation grafting is performed with the polymer first irradiated in the absence of oxygen and then contacted with an oxygen-free solution of the organic phosphate. ### Claim 34 (depends on 27) The adsorbent material according to claim 27, wherein the radiation grafting is performed with the polymer irradiated while immersed in an oxygen-free solution of the organic phosphate. ### Claim 35 (depends on 27) The adsorbent material according to claim 27, wherein the polymer is irradiated while immersed in an oxygen-free solution containing components selected from the group consisting of surfactants, polar organic liquids, and combinations thereof. ### Claim 36 (depends on 27) The adsorbent material according to claim 27, wherein the radiation grafting is characterized by a degree of grafting, defined as the weight gain of the polymer upon grafting and drying relative to its original weight, that is between 25% and 250%. ### Claim 37 (depends on 36) The adsorbent material according to claim 36, wherein the degree of radiation grafting is between 50% and 200%. ### Claim 38 (depends on 37) The adsorbent material according to claim 37, wherein the degree of radiation grafting is between 80% and 150%. ### Claim 39 (depends on 27) The adsorbent material according to claim 27, wherein the polymer is sonicated following radiation grafting to remove homopolymerized material. ### Claim 40 A method of removing uranium from an aqueous solution comprising the steps of: providing an adsorbent material produced by using a source of ionizing radiation to graft bis(2-methacryloxyethyl) phosphate onto a polymer; contacting the grafted polymer with the aqueous solution that includes uranium such that the adsorbent material removes an amount of uranium, at least 0.1%, relative to the dry weight of the polymer, from the aqueous solution; and regenerating the adsorbent material at least once through desorption of the uranium using a near-neutral solution of a complexing reagent that is an aqueous solution of ammonium oxalate to remove the uranium from the phosphate-grafted polymer. ### Claim 41 (depends on 40) The method of removing uranium from an aqueous solution according to claim 40, wherein the adsorbent material removes uranium from an aqueous solution that is one of brine or seawater. ### Claim 42 (depends on 40) The method of removing uranium from an aqueous solution according to claim 40, wherein, following adsorption of uranium from the aqueous solution followed by regeneration with an aqueous solution of ammonium oxalate, the distribution coefficient of the regenerated adsorbent material is greater than 250. ### Claim 43 (depends on 42) The method of removing uranium from an aqueous solution according to claim 42, wherein the distribution coefficient of the regenerated adsorbent material is greater than 500. ### Claim 44 (depends on 40) The method of removing uranium from an aqueous solution according to claim 40, wherein, following at least 15 cycles of adsorption of uranium from the aqueous solution followed by regeneration with an aqueous solution of ammonium oxalate, the distribution coefficient of the regenerated adsorbent material is greater than 250. ### Claim 45 (depends on 44) The method of removing uranium from an aqueous solution according to claim 44, wherein the distribution coefficient of the regenerated adsorbent material is greater than 500. ### Claim 46 (depends on 41) The method of removing uranium from an aqueous solution according to claim 41, wherein, following at least 15 cycles of adsorption of uranium from the brine or seawater followed by regeneration with an aqueous solution of ammonium oxalate, the distribution coefficient of the regenerated adsorbent material is greater than 250. ### Claim 47 (depends on 46) The method of removing uranium from an aqueous solution according to claim 46, wherein the distribution coefficient of the regenerated adsorbent material is greater than 500. ### Claim 48 (depends on 41) The method of removing uranium from an aqueous solution according to claim 41, wherein, following at least 15 cycles of adsorption of uranium from the brine or seawater followed by regeneration with an aqueous solution of ammonium oxalate, the distribution coefficient of the regenerated adsorbent material is greater than 250. ### Claim 49 (depends on 48) The method of removing uranium from an aqueous solution according to claim 48, wherein the distribution coefficient of the regenerated adsorbent material is greater than 500. ### Claim 50 (depends on 40) The method of removing uranium from an aqueous solution according to claim 40, wherein the radiation grafting of bis(2-methacryloxyethyl) phosphate onto the polymer is performed by radiation grafting bis(2-methacryloxyethyl) phosphate onto a polymeric fiber having a surface area of at least 10 m2/gram. ### Claim 51 (depends on 50) The method of removing uranium from an aqueous solution according to claim 50, wherein the radiation grafting bis(2-methacryloxyethyl) phosphate onto the polymeric fiber having a surface area of at least 10 m2/gram is performed by radiation grafting bis(2-methacryloxyethyl) phosphate onto polycaproamide. ### Claim 52 (depends on 40) The method of removing uranium from an aqueous solution according to claim 40, wherein the source of ionizing radiation is a gamma source providing a total radiation dose of 0.2-50 kGy to effect the radiation grafting. ### Claim 53 (depends on 52) The method of removing uranium from an aqueous solution according to claim 52, wherein the gamma source provides a total radiation dose of 1-10 kGy to effect the radiation grafting. ### Claim 54 (depends on 40) The method of removing uranium from an aqueous solution according to claim 40, wherein the radiation grafting is performed with the polymer first irradiated in the absence of oxygen and then contacted with an oxygen-free solution of the organic phosphate. ### Claim 55 (depends on 40) The method of removing dissolved uranium from an aqueous solution according to claim 40, wherein the radiation grafting is performed with the polymer irradiated while immersed in an oxygen-free solution of the organic phosphate. ### Claim 56 (depends on 40) The method of removing uranium from an aqueous solution according to claim 40, wherein the step of contacting the grafted polymer with the aqueous solution includes contacting the grafted polymer with a solution containing components selected from the group consisting of surfactants, polar organic liquids, and combinations thereof. ### Claim 57 (depends on 40) The method of removing uranium from an aqueous solution according to claim 40, wherein the radiation grafting is characterized by a degree of grafting, defined as the weight gain of the polymer upon grafting and drying relative to its original weight, that is between 25% and 250%. ### Claim 58 (depends on 57) The method of removing uranium from an aqueous solution according to claim 57, wherein the degree of radiation grafting is between 50% and 200%. ### Claim 59 (depends on 58) The method of removing uranium from an aqueous solution according to claim 58, wherein the degree of radiation grafting is between 80% and 150%. ### Claim 60 (depends on 40) The method of removing uranium from an aqueous solution according to claim 40, wherein the polymer is sonicated following radiation grafting to remove homopolymerized material.