Liquid-liquid Extracting Patents (Class 423/8)
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Patent number: 7282187Abstract: A process for selectively extracting metal values, including, uranium, thorium, scandium and zirconium, from starting materials which include the metal values. The process is particularly well suited to extracting metal and recovering metal values from tantalum/niobium production process ore residues.Type: GrantFiled: March 26, 1996Date of Patent: October 16, 2007Assignee: Caboi CorporationInventors: Patrick M. Brown, Robert A Hard, Donna D. Harbuck, G. Kyle Green
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Patent number: 7157061Abstract: A method of recovering daughter isotopes from a radioisotope mixture. The method comprises providing a radioisotope mixture solution comprising at least one parent isotope. The at least one parent isotope is extracted into an organic phase, which comprises an extractant and a solvent. The organic phase is substantially continuously contacted with an aqueous phase to extract at least one daughter isotope into the aqueous phase. The aqueous phase is separated from the organic phase, such as by using an annular centrifugal contactor. The at least one daughter isotope is purified from the aqueous phase, such as by ion exchange chromatography or extraction chromatography. The at least one daughter isotope may include actinium-225, radium-225, bismuth-213, or mixtures thereof. A liquid-liquid extraction system for recovering at least one daughter isotope from a source material is also disclosed.Type: GrantFiled: September 24, 2004Date of Patent: January 2, 2007Assignee: Battelle Energy Alliance, LLCInventors: David H. Meikrantz, Terry A. Todd, Troy J. Tranter, E. Philip Horwitz
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Patent number: 7157003Abstract: The invention concerns a cyclic method for separating at least one chemical element E1 from at least one chemical element E2 from an aqueous solution containing said elements, which employs a mixture of two extractants operating in non-overlapping chemical fields. Each cycle of said method comprises: a) co-extracting elements E1 and E2 by means of an organic phase containing a first extractant suited to causing the migration of said elements into said organic phase; b) adding to the organic phase a second extractant suited to selectively retaining the element(s) E2 in said organic phase during step c): c) selectively stripping the element(s) E1 from the organic phase; d) selectively stripping the element(s) E2 from the organic phase; e) separating the first and second extractants present in said organic phase at the end of step d).Type: GrantFiled: October 7, 2003Date of Patent: January 2, 2007Assignee: Commissariat A L'Energie AtomiqueInventors: Pascal Baron, Michael Lecomte, Xavier Heres, Bernard Mauborgne
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Patent number: 7063792Abstract: A method for separating a metal (a) from a metal (2), preferably zirconium from hafnium, which consists in dissolving said metals in an aqueous solution wherein said metals are in a state preventing them from passing through a nanofiltration membrane; treating the aqueous medium with a ligand, for example EDTA, which is complexed with metal (1) and/or metal (2), then in passing the resulting treated medium on a filtering membrane allowing through the ligand-metal complexes, but retaining the metals not complexed with the ligand.Type: GrantFiled: September 10, 2001Date of Patent: June 20, 2006Assignee: Compagnie Europeenne du Zirconium CEZUSInventors: Noël Ozanne, Marc Lionel Lemaire, Alain Jean-Louis Guy, Jacques Henri Foos, Stéphane Pellet-Rostaing, Frédéric Chitry
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Patent number: 7025899Abstract: The preparation of concentrated solutions of oxime metal extractants, such as aldoximes and ketoximes, or mixtures of aldoxime and ketoxime, and the use thereof in formulating or preparing extraction reagent compositions for use in an extractant organic phase in a process of extracting metals from aqueous solutions containing metal values; and in particular, to concentrates which are solutions of individual ketoxime or aldoxime or mixtures of water-insoluble hydroxy aldoximes and ketoximes, in varying ratios by weight of 1:100 aldoxime to ketoxime, or conversely, 100:1 ketoxime to aldoxime, in water-immiscible hydrocarbon solvents or equilibrium modifiers. The invention also provides for maintaining stability of concentrates determined by accelerating rate calorimetry to define the ranges of oxime concentration and volume whereby the concentrate will be a stable, flowable, pourable and pumpable concentrate which can be safely stored long term.Type: GrantFiled: December 21, 2001Date of Patent: April 11, 2006Assignee: Cognis CorporationInventors: R. Brantley Sudderth, George A. Wolfe, Ralph L. Jensen, Gary A. Kordosky, Michael J. Virnig, Mary Collins, Stephen M. Olafson, Terry L. Crandell, Hans C. Hein
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Patent number: 6998052Abstract: A multicolumn selectivity inversion generator separation method has been developed in which a desired daughter radionuclide is selectively extracted from a solution of the parent and daughter radionuclides by a primary separation column, stripped, and passed through a second guard column that retains any parent or other daughter impurities, while the desired daughter elutes. This separation method minimizes the effects of radiation damage to the separation material and permits the reliable production of radionuclides of high chemical and radionuclidic purity for use in diagnostic or therapeutic nuclear medicine.Type: GrantFiled: April 9, 2003Date of Patent: February 14, 2006Assignee: PG Research FoundationInventors: E. Philip Horwitz, Andrew H. Bond
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Publication number: 20040247504Abstract: A two-cycle countercurrent extraction process for recovery of highly pure uranium from fertilizer grade weak phosphoric acid. The proposed process uses selective extraction using di-(2-ethyl hexyl) phosphoric acid (D2EHPA) and tri-n-butyl phosphate (TBP) with refined kerosene as synergistic extractant system on hydrogen peroxide treated phosphoric acid, and stripping the loaded extract with strong phosphoric acid containing metallic iron to lower redox potential. The loaded-stripped acid is diluted with water back to weak phosphoric acid state and its redox potential raised by adding hydrogen peroxide and re-extracted with same extractant system. This extract is first scrubbed with sulfuric acid and then stripped with alkali carbonate separating iron as a precipitate, treated with sodium hydroxide precipitating sodium uranate, which is re-dissolved in sulfuric acid and converted with hydrogen peroxide to highly pure yellow cake of uranium peroxide.Type: ApplicationFiled: February 11, 2004Publication date: December 9, 2004Inventors: Harvinderpal Singh, Shyamkant Laxmidutt Mishra, Anitha Mallavarapu, Vijayalakshmi Ravishankar, Ashok Giriyalkar, Manojkumar Kedarnath Kotekar, Tapan Kumar Mukherjee
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Publication number: 20040202595Abstract: A treatment for waste pickling solutions containing iron and method of ferric oxide formation, consisting of spent acid with iron content, the addition therein of sodium hydroxide to adjust the pH value, the execution of a chemical reaction in another tank into which sodium hydroxide and air are added while the admixture is exposed to an ultraviolet beam circuit in a photo-oxidation process, and finally magnetic culling to separate ferric oxide in the solution.Type: ApplicationFiled: October 2, 2003Publication date: October 14, 2004Inventors: Ton-Shyun Lin, Po-Jung Tseng, Jong-Kang Huang, Min-Shin Lin
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Patent number: 6780384Abstract: A method of recovering zirconium values from an ore containing zircon, baddeleyite, and uranium is disclosed. The method includes fusing the ore with soda ash and contacting the resulting fused ore with sulfuric acid, which generates an acid leach liquor that contains zirconium and uranium values and solids that comprise baddeleyite and silica. Baddeleyite is recovered by contacting it with sulfuric acid to convert baddeleyite to zirconium sulfate, which can be dissolved in the acid leach liquor. The method also includes separating zirconium from uranium by solvent extraction followed by precipitation.Type: GrantFiled: March 7, 2002Date of Patent: August 24, 2004Assignee: Cotter Corporation (NSL)Inventors: Allen L. Williams, Robert W. Philips, Jr., David R. Tierney, Daniel R. Dilday
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Patent number: 6623710Abstract: A spent fuel reprocessing method including the steps of partitioning U and Pu(III) in a solvent by solvent extraction and subsequently polishing the solvent in a neptunium rejection operation for removing Np therefrom. The solvent obtained from the neptunium rejection operation (the polished solvent or NpA solvent product) is then recycled to a U/Pu partitioning operation. The method enables a reduction in solvent feed and solvent effluent volumes.Type: GrantFiled: September 29, 2000Date of Patent: September 23, 2003Assignee: British Nuclear Fuels PLCInventors: Emmanuel Gaubert, Gavin Paul Towler, Andrew Lindsay Wallwork
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Publication number: 20030113247Abstract: An improved process of extraction of uranium from phosphoric acid and in particular uranium VI from phosphoric acid especially strong phosphoric acid using a selective synergistic extractant mix of an organo-phosphorous acid and a neutral extraction agent. The process basically involves the steps of extraction comprising contacting said acid with a selective synergistic extractant system of di-nonyl phenyl phosphoric acid (DNPPA) and a neutral agent selected from di-butyl butyl phosphonate (DBBP) and tri-n-octyl phosphine oxide (TOPO); and recovering the uranium values from the loaded organic phase. The above process would provide for an improved process for recovery of uranium both from weak and strong phosphoric acids using a stable and relatively cheap extractant system. The process is directed to improved recovery of U-VI from phosphoric acid by way of a simple, industrially applicable and cost-effective process.Type: ApplicationFiled: September 7, 2001Publication date: June 19, 2003Inventors: Harvinderpal Singh, Shyamkant Laxmidutt Mishra, Ravishankar Vijayalakshmi, Ashok Basawanthappa Giriyalkar, Chiranjib Kumar Gupta
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Patent number: 6533938Abstract: A method is describe for removing metal ions of interest from aqueous solutions containing low concentrations of the metal ions of interest. The method involves the use of a microbially produced polymer, &ggr;-glutamic acid. The polymer is used in conjunction with tangential flow filtration and results in substantial removal of metal ions.Type: GrantFiled: May 26, 2000Date of Patent: March 18, 2003Assignee: Worcester Polytechnic InstitueInventors: Alexander Dilorio, Sonny Mark, Philip A. Tongue
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Patent number: 6379634Abstract: A method of dissolving in an ionic liquid a metal in an initial oxidation state below its maximum oxidation state, characterized in that the ionic liquid reacts with the metal and oxidizes it to a higher oxidation state. The initial metal may be in the form of a compound thereof and may be irradiated nuclear fuel comprising UO2 and/or PuO2 as well as fission products. The ionic liquid typically is nitrate-based, for example a pyridinium or substituted imidazolium nitrate, and contains a Bronstead or Franklin acid to increase the oxidizing power of the nitrate. Suitable acids are HNO3, H2SO4 and [NO+]. Imidazolium nitrates and certain pyridinium nitrates form one aspect of the invention.Type: GrantFiled: July 2, 1999Date of Patent: April 30, 2002Assignee: British Nuclear Fuels PlcInventors: Mark Fields, Graham Victor Hutson, Kenneth Richard Seddon, Charles Mackintosh Gordon
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Patent number: 6328782Abstract: The present invention provides a novel process for the removal and recovery of radionuclides from waste waters and process streams. The process of the present invention utilizes a combination of a supported liquid membrane (SLM) and a strip dispersion to improve extraction of the target species while increasing membrane stability and reducing processing costs. Additionally, the invention provides a family of new extractants, alkyl phenylphosphonic acids, for the removal and recovery of radionuclides and/or metals, including the use of the new extractants in the process. The new extractant selectively removes radionuclides and metals from the feed stream to provide a concentrated strip solution of the target species.Type: GrantFiled: February 4, 2000Date of Patent: December 11, 2001Assignee: Commodore Separation Technologies, Inc.Inventor: W. S. Winston Ho
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Patent number: 6270737Abstract: Cesium and strontium are extracted from aqueous acidic radioactive waste containing rare earth elements, technetium and actinides, by contacting the waste with a composition of a complex organoboron compound and polyethylene glycol in an organofluorine diluent mixture. In a preferred embodiment the complex organoboron compound is chlorinated cobalt dicarbollide, the polyethylene glycol has the formula RC6H4(OCH2CH2)nOH, and the organofluorine diluent is a mixture of bis-tetrafluoropropyl ether of diethylene glycol with at least one of bis-tetrafluoropropyl ether of ethylene glycol and bis-tetrafluoropropyl formal. The rare earths, technetium and the actinides (especially uranium, plutonium and americium), are extracted from the aqueous phase using a phosphine oxide in a hydrocarbon diluent, and reextracted from the resulting organic phase into an aqueous phase by using a suitable strip reagent.Type: GrantFiled: March 3, 2000Date of Patent: August 7, 2001Assignee: The United States of America as represented by the United States Department of EnergyInventors: Boris N. Zaitsev, Vyacheslav M. Esimantovskiy, Leonard N. Lazarev, Evgeniy G. Dzekun, Valeriy N. Romanovskiy, Terry A. Todd, Ken N. Brewer, Ronald S. Herbst, Jack D. Law
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Method for the simultaneous recovery of radionuclides from liquid radioactive wastes using a solvent
Patent number: 6258333Abstract: The present invention relates to solvents, and methods, for selectively extracting and recovering radionuclides, especially cesium and strontium, rare earths and actinides from liquid radioactive wastes. More specifically, the invention relates to extracting agent solvent compositions comprising complex organoboron compounds, substituted polyethylene glycols, and neutral organophosphorus compounds in a diluent. The preferred solvent comprises a chlorinated cobalt dicarbollide, diphenyl-dibutylmethylenecarbamoylphosphine oxide, PEG-400, and a diluent of phenylpolyfluoroalkyl sulfone. The invention also provides a method of using the invention extracting agents to recover cesium, strontium, rare earths and actinides from liquid radioactive waste.Type: GrantFiled: October 7, 1999Date of Patent: July 10, 2001Assignee: The United States of America as represented by the United States Department of EnergyInventors: Valeriy Nicholiavich Romanovskiy, Igor V. Smirnov, Vasiliy A. Babain, Terry A. Todd, Ken N. Brewer -
Patent number: 6238566Abstract: Proposed is an improvement in a multi-stage solvent extraction process of a metal value such as rare earth elements from an acidic feed solution containing the metal value in the form of a water-soluble salt by bringing the aqueous solution into contact with a water-immiscible organic extractant solution containing an extractant compound which releases an acid when combined with the metal ions.Type: GrantFiled: February 17, 1998Date of Patent: May 29, 2001Assignee: Shin-Etsu Chemical Co., Ltd.Inventors: Norifumi Yoshida, Jun-ichi Nakayama
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Patent number: 6093375Abstract: A spent fuel reprocessing method includes at least the formation of an aqueous solution and at least one solvent extraction step. Formohydroxarmic acid is used to reduce any Np(VI) to Np(V) and/or to form a complex with Np(IV). As a result, substantially all the neptunium present is retained in the aqueous phase during solvent extraction.Type: GrantFiled: August 7, 1998Date of Patent: July 25, 2000Assignee: British Nuclear Fuels PLCInventors: Robin John Taylor, Iain Stewart Denniss, Andrew Lindsay Wallwork
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Patent number: 5966584Abstract: Trivalent actinides can be separated from trivalent lanthanides in aqueous solutions at H.sup.+ concentrations of 2 mol/l to 0.001 mol/liter by extraction with bis(aryl)dithiophosphinic acid and a synergist such as TBP, TOPO and TBPO in an organic solvent. A high separation efficiency results. The method is applicable to high-level liquid waste from reactors and nuclear-material processing plants.Type: GrantFiled: September 17, 1997Date of Patent: October 12, 1999Assignee: Forschungszentrum Julich GmbHInventors: Giuseppe Modolo, Reinhard Odoj
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Patent number: 5965025Abstract: A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent is described. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated .beta.-diketone. In especially preferred embodiments the extraction solvent is supercritical carbon dioxide, and the chelating agent comprises a fluorinated .beta.-diketone and a trialkyl phosphate, or a fluorinated .beta.-diketone and a trialkylphosphine oxide. Although a trialkyl phosphate can extract lanthanides and actinides from acidic solutions, a binary mixture comprising a fluorinated .beta.-diketone and a trialkyl phosphate or a trialkylphosphine oxide tends to enhance the extraction efficiencies for actinides and lanthanides.Type: GrantFiled: January 21, 1998Date of Patent: October 12, 1999Assignee: Idaho Research Foundation, Inc.Inventors: Chien M. Wai, Kenneth E. Laintz
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Patent number: 5928616Abstract: In a solvent extraction method a contactor comprises a forward extraction section comprising sub-sections thereof and a back extraction section comprising sub-sections thereof. To enable higher concentrations of solute to be obtained in the backwash liquor, the contactor is operated with recycle of partially-loaded solvent, via a line from a back extraction sub-section to a forward extraction sub-section.Type: GrantFiled: May 22, 1995Date of Patent: July 27, 1999Assignee: British Nuclear Fuels PLCInventor: Geoffrey Horrocks Bailey
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Patent number: 5926687Abstract: The invention relates to crown calix.vertline.4.vertline.arenes, their preparation process and their use for the selective extraction of cesium and actinides. These crown calixl4larenes comply with the formula: ##STR1## in which R.sub.1 represents a group of formula X(C.sub.2 H.sub.4 X).sub.m and X(C.sub.2 H.sub.4 X).sub.n YX(C.sub.2 H.sub.4 X).sub.n with X=O or N(R.sub.4), m=3, 4, 5 or 6, Y=cycloalkylene or arylene and n=1, 2 or 3. These crown.vertline.4.vertline.arenes, whose benzene nuclei are optionally substituted by alkyl groups, can be used as extractants, e.g. in liquid membrane form, for separating cesium from acid solutions containing sodium in a large quantity compared with the cesium quantity, e.g. irradiated fuel reprocessing plant effluents.Type: GrantFiled: October 4, 1995Date of Patent: July 20, 1999Assignee: Commissariat a l'Energie AtomiqueInventors: Jean-Fran.cedilla.ois Dozol, Helene Rouquette, Rocco Ungaro, Alessandro Casnati
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Patent number: 5888397Abstract: A solid/liquid process for the separation and recovery of chaotropic anions from an aqueous solution is disclosed. The solid support comprises separation particles having surface-bonded poly(ethylene glycol) groups, whereas the aqueous solution from which the chaotropic anions are separated contains a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved salt (lyotrope). A solid/liquid phase admixture of separation particles containing bound chaotropic anions in such an aqueous solution is also contemplated, as is a chromatography apparatus containing that solid/liquid phase admixture.Type: GrantFiled: June 7, 1995Date of Patent: March 30, 1999Assignees: ARCH Develop. Corp., The Board of Regents for Northern Illinois UniversityInventors: Robin Rogers, E. Philip Horwitz, Andrew H. Bond
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Patent number: 5881358Abstract: A composition for extracting a transition metal which comprises as an active ingredient a cyclic phenol sulfide represented by the following formula (1): ##STR1## wherein X represents a hydrogen atom, a hydrocarbon group, an acyl group, a carboxyalkyl group, or a carbamoylalkyl group; Y represents a hydrocarbon group; Z represents a sulfide group, a sulfinyl group, or a sulfonyl group; and n is an integer of 4 to 8; and a method for extracting a transition metal using the compositionType: GrantFiled: December 24, 1997Date of Patent: March 9, 1999Assignees: Cosmo Research Institute, Cosmo Oil Co., Ltd.Inventors: Sotaro Miyano, Nobuhiko Iki, Fumitaka Narumi, Naoya Morohashi, Hitoshi Kumagai
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Patent number: 5863439Abstract: A process for preconcentrating and separating radium from a contaminated solution containing at least water and radium includes the steps of adding a quantity of a water-soluble macrocyclic polyether to the contaminated solution to form a combined solution. An acid is added to the combined solution to form an acidic combined solution having an ?H.sup.+ ! concentration of about 0.5M. The acidic combined solution is contacted with a sulfonic acid-based strong acid cation exchange medium or a organophilic sulfonic acid medium having a plurality of binding sites thereon to bind the radium thereto and to form a radium-depleted solution. The radium-depleted solution is separated from the strong acid cation exchange medium or organophilic sulfonic acid medium. The radium remaining bound to the exchange medium or organophilic reagent is then stripped from the exchange medium or organophilic medium and the activity of the radium is measured.Type: GrantFiled: June 6, 1997Date of Patent: January 26, 1999Assignee: Arch Development CorporationInventors: Mark Dietz, E. Philip Horwitz, Renato Chiarizia, Richard A. Bartsch
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Patent number: 5826161Abstract: The present invention relates to a process for the selective separation of actinides (III) and lanthanides (III) from a reaction medium containing them. More specifically, the invention permits a selective extraction of actinides (III) by using an aqueous reaction medium containing TcO.sub.4.sup.- pertechnetate ions. The preferred extracting agents are chosen from among picolinamides and their derivatives. A particular use of the process is in the separation of actinides (III) from high activity raffinates produced during the reprocessing of nuclear fuels according to the solvent-based extraction process known as the PUREX process.Type: GrantFiled: May 15, 1997Date of Patent: October 20, 1998Assignees: Commissariat a l'Energie Atomique, Compagnie Generale des Matieres NucleairesInventors: Charles Madic, Pierre-Yves Cordier
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Patent number: 5792357Abstract: A method of extracting metal and metalloid species from a solid or liquid substrate using a supercritical fluid solvent containing one or more chelating agents followed by back-extracting the metal and metalloid species from the metal and metalloid chelates formed thereby. The back-extraction acidic solution is performed utilizing an acidic solution. Upon sufficient exposure of the metal and metalloid chelates to the acidic solution, the metal and metalloid species are released from the chelates into the acid solution, while the chelating agent remains in the supercritical fluid solvent. The chelating agent is thereby regenerated and the metal and metalloid species recovered.Type: GrantFiled: July 26, 1996Date of Patent: August 11, 1998Assignee: Idaho Research Foundation, Inc.Inventors: Chien M. Wai, Neil G. Smart, Yuehe Lin
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Patent number: 5766478Abstract: A process of selectively separating a target metal contained in an aqueous solution by contacting the aqueous solution containing a target metal with an aqueous solution including a water-soluble polymer capable of binding with the target metal for sufficient time whereby a water-soluble polymer-target metal complex is formed, and, separating the solution including the water-soluble polymer-target metal complex from the solution is disclosed.Type: GrantFiled: May 30, 1995Date of Patent: June 16, 1998Assignee: The Regents of the University of California, Office of Technology TransferInventors: Barbara F. Smith, Thomas W. Robison
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Patent number: 5758255Abstract: A method of reducing the entrainment of aqueous mineral acid solutions in organic extractants used in the solvent extraction of metals from the aqueous fluid is disclosed. The method comprises adding an effective, entrainment prevention amount of a water soluble cationic polymer having a molecular weight of from about 10,000 to about 500,000 to a metal rich aqueous mineral acid solution, immediately prior to, or during mixing with a metal poor organic extractant, and then recovering a metal poor aqueous mineral acid phase, and a metal rich organic extractant phase having a reduced level of entrainment of the aqueous mineral acid solution. In a preferred embodiment the metal is copper, and the polymer is poly(diallyldimethylammonium) chloride.Type: GrantFiled: August 19, 1996Date of Patent: May 26, 1998Assignee: Nalco Chemical CompanyInventors: E. Michael Kerr, Kenneth M. Smith, II
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Patent number: 5750081Abstract: A method of extracting metal species from a metal species containing medium which comprises contacting the medium with an extractant solvent which comprises a supercritical fluid and a complexant for solubilizing metal species in the said medium and also a conditioning agent for changing the oxidation state of the metal species.Type: GrantFiled: January 31, 1996Date of Patent: May 12, 1998Assignee: British Nuclear Fuels plcInventor: Neil Graham Smart
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Patent number: 5708958Abstract: A method is provided for separating trivalent actinides and rare earth elements in the TRUEX method using a CMPO-TBP mixed solvent. The method of separating trivalent actinides and rare earth elements comprises a trivalent actinide/rare earth extraction step wherein trivalent actinides and rare earth elements are extracted by a solvent from highly acid waste generated by reprocessing of spent nuclear fuel, a nitric acid removal step wherein the nitric acid concentration of the solvent used to extract the trivalent actinides and rare earth elements is reduced, and a separation step wherein the trivalent actinides and rare earth elements contained in the solvent of low nitric acid concentration, are separated from each other.Type: GrantFiled: August 12, 1996Date of Patent: January 13, 1998Assignee: Doryokuro Kakunenryo Kaihatsu JigyodanInventors: Yoshikazu Koma, Masayuki Watanabe, Shinichi Nemoto
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Patent number: 5666642Abstract: Methods and agents for extracting cesium and strontium ions from aqueous solutions, including aqueous fission product waste solutions, are disclosed using substituted metal dicarbollide ions containing one or more chemical groups that increase solubility of the substituted metal dicarbollide ion in non-nitrated, non-chlorinated solvents, or using metal dicarbollide ion-substituted silicones.Type: GrantFiled: April 21, 1995Date of Patent: September 9, 1997Assignee: Coremetals Research, Inc.Inventors: M. Frederick Hawthorne, Gary B. Dunks
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Patent number: 5463177Abstract: The extraction process includes supplying solvent under gas pressure for introduction of the solvent adjacent the bottom of a vessel containing the sample. The vessel lies in a water bath and ultrasonic energy is applied to the bath and hence to the sample to facilitate interaction between the solvent and the sample. Because the solvent is immiscible in the sample and of lesser density, the solvent and solubilized material rise to the top of the vessel. An extraction tube under vacuum pressure continuously removes the solvent with the solubilized material.Type: GrantFiled: August 23, 1994Date of Patent: October 31, 1995Assignee: General Electric CompanyInventor: John K. Youngs
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Patent number: 5422084Abstract: The invention relates to a process for dissolving plutonium dioxide by means of OH.sup.- radicals produced by radiolysis of water and usable for the treatment of dissolving fines and plutoniferous waste.To this end, contacting takes place in a reactor (1) of solid products containing PuO.sub.2 coming from the hopper (5) with an aqueous nitric solution (3) irradiated by radiation or charged particles for producing OH.sup.- radicals by radiolysis of said solution, in the presence of a reagent such as N.sub.2 O, able to trap the solvated electrons and the H.sup.- radicals produced in simultaneous manner and optionally a redox mediator such as silver.Irradiation can take place by an alpha or beta emitter present in the solution or by an external source such as an irradiator or an electron accelerator.Type: GrantFiled: March 5, 1993Date of Patent: June 6, 1995Inventor: Charles Madic
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Patent number: 5419887Abstract: The isotopes of boron, .sup.10 B and .sup.11 B, are separated by means of a gas-liquid chemical exchange reaction involving the isotopic equilibrium between gaseous BF.sub.3 and a liquid BF.sub.3 . donor molecular addition complex formed between BF.sub.3 gas and a donor chosen from the group consisting of: nitromethane, acetone, methyl isobutyl ketone, or diisobutyl ketone.Type: GrantFiled: January 25, 1994Date of Patent: May 30, 1995Assignee: Research & Development Institute, Inc.Inventors: Frank P. McCandless, Ronald S. Herbst
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Patent number: 5344624Abstract: The invention concerns the recovery of Pu (IV) by using crown compounds.According to the invention, the aqueous solution containing the plutonium (IV) is placed in contact with at least one crown compound, for example DCH 18C6, dissolved in an organic diluting agent, such as benzonitrile. In the case where the solution only contains traces of Pu, it is possible to use a crown compound secured to a solid phase, such as silica.The aqueous solution is a concentrated solution of fission products, an effluent originating from an irradiated nuclear fuel reprocessing installation or a concentrated solution of plutonium with americium.Type: GrantFiled: August 25, 1992Date of Patent: September 6, 1994Assignee: Cogema-Compagnie Generale des Matieres NucleairesInventors: Jacques Foos, Marc Lemaire, Alain Guy, Vincent Guyon, Rodolphe Chomel, Andre Delo Ge, Pierre Doutreluigne, Henri Le Roy
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Patent number: 5183645Abstract: The invention concerns the recovery of Pu (IV) by using crown compounds.According to the invention, the aqueous solution containing the plutonium (IV) is placed in contact with at least one crown compound, for example DCH 18C6, dissolved in an organic diluting agent, such as benzonitrile. In the case where the solution only contains traces of Pu, it is possible to use a crown compound secured to a solid phase, such as silica.The aqueous solution is a concentrated solution of fission products, an effluent originating from an irradiated nuclear fuel reprocessing installation or a concentrated solution of plutonium with americium.Type: GrantFiled: December 11, 1990Date of Patent: February 2, 1993Assignee: Cogema-Compagnie Generale des Matieres NucleariesInventors: Jacques Foos, Marc Lemaire, Alain Guy, Vincent Guyon, Rodolphe Chomel, Andre Deloge, Pierre Doutreluigne, Henri Le Roy
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Patent number: 5171546Abstract: The invention relates to the use of thioether ligands in accordance with the formula: ##STR1## in which R.sup.1 and R.sup.2, which can be the same or different, represent alkyl radicals, R.sup.3 is an alkyl radical and A represents a divalent radical chosen from among the radicals of formula:--(CH.sub.2).sub.m ----(CH.sub.2).sub.n --X--(CH.sub.2).sub.p -- ##STR2## in which m is equal to 0 or is an integer from 1 to 6, n and p are integers between 1 and 6 and X represents O or S, for recovering the palladium present in a nitric aqueous solution (A.sub.0) for dissolving irradiated nuclear fuel elements.For example, it is possible to use the ligand of formula (I) with A representing CH.sub.2 --S--CH.sub.2 and R.sup.1 and R.sup.2 representing C.sub.10 H.sub.21.Type: GrantFiled: May 14, 1991Date of Patent: December 15, 1992Assignee: Cogema-Compagnie Generale des Matieres NucleairesInventors: Alain Guy, Marc Lemaire, Jacques Foos, Gerard Le Buzit, Vincent Guyon, Thierry Moutarde, Rodolph Chomel, Micheline Draye
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Patent number: 5085834Abstract: A method for separating plutonium from uranium and from fission products with the aid of crown ether compounds comprising contacting an aqueous solution A0 containing Pu, U and fission products with an organic solvent O0 containing at least one crown ether compound to obtain an organic solution O1 containing Pu and U; extracting U from the organic solution O1 with an aqueous solution A4 such as water or nitric acid to obtain an aqueous solution A5 containing U and an organic solution O3 containing mainly of Pu and recovering Pu from the organic solution using an aqueous solution A6 such as sulfuric acid.Type: GrantFiled: December 11, 1990Date of Patent: February 4, 1992Assignee: Cogema-Compaignie Generale des Matieres NucleairesInventors: Marc Lemaire, Alain Guy, Jacques Foos, Rodolphe Chomel, Pierre Doutreluigne, Thierry Moutarde, Vincent Guyon, Henri Le Roy
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Patent number: 5057289Abstract: A process for the separation of uranium and plutonium as well as fission ducts including technetium from a nitric acid feed solution (fuel solution) in which said solution is treated with an extraction agent in an organic solvent to charge said agent with U, Pu and fission products including technetium by the counterflow process. The charged extraction agent containing U, Pu and fission products including technetrium is treated with a washing solution and subsequently with a reducing agent for the separation of the uranium from the plutonium and from fission products including technetium not previously washed out. To improve the separation of uranium and obtain a cleaner uranium end product, the treatment of the organic solvent containing said charged agent with reducing agent is effected in one or more stages by the crossflow process instead of by the counterflow process.Type: GrantFiled: March 9, 1989Date of Patent: October 15, 1991Assignee: Deutsche Gesellschaft fur Wideraufarbeitung von Kernbrennstoffen mbHInventors: Wolfgang Issel, Werner Knoch, Hartmut Ramm
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Patent number: 5035840Abstract: A process for removing metal salts from an H.sub.4 EDTA precipitate by esterification with an esterification reagent to produce an esterification mixture comprising a solid metal salt an EDTA ester and thereafter separating the solid metal salt from the esterification mixture.Type: GrantFiled: October 1, 1990Date of Patent: July 30, 1991Assignee: Chemical Waste Management, Inc.Inventor: Yuval Halpern
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Patent number: 5028402Abstract: Process for separating plutonium from uranium contained in a nitric acid aqueous solution from the reprocessing of irradiated fuels comprising plutonium, uranium and fission products by means of crown ethers. Nitric acid aqueous solution (5) containing plutonium, uranium and fission products is contacted at (2) with an organic liquid membrane (3) containing a crown ether. The uranium and plutonium are extracted in the liquid membrane (3) and then transferred by said membrane into a receiving solution (7), which becomes enriched with uranium, because the latter is transferred more rapidly than the plutonium. The crown ether can be DCH 18 C6 or DB 18 C6.Type: GrantFiled: June 16, 1989Date of Patent: July 2, 1991Assignee: Cogema Compagnie General des Matieres NucleairesInventors: Jacques Foos, Pierre Epherre, Alain Guy, Marc Lemaire, Rodolph Chomel, Gerard Cauquil, Pierre Patigny, Alain Vian
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Patent number: 4968504Abstract: The separation of uranium, iron and scandium is achieved by the following process wherein a material containing these values is dissolved in mineral acid to form an aqueous solution, thereafter, an iminodiacetic acid cationic ion exchange resin is used to retain a major portion of the scandium and uranium. A raffinate containing the iron is formed. The ion exchange resin having said scandium and uranium retained thereon is rinsed with a dilute acid to remove residual metals other than scandium and uranium. The resin is eluted with an aqueous solution of an organic chelating acid to remove a major portion of the scandium from said resin and to form an aqueous solution containing scandium. The resin is then eluted with an aqueous solution of a mineral acid to remove a major portion of the uranium from the resin to form an aqueous solution containing the uranium. The scandium and uranium are recovered as solids.Type: GrantFiled: October 19, 1989Date of Patent: November 6, 1990Assignee: GTE Laboratories IncorporatedInventor: William J. Rourke
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Patent number: 4954293Abstract: Thorium and rare earth values are separated from a fluoride concentrate thereof, by decomposing such concentrate with aqueous sodium hydroxide under conditions such that the amount of sodium hydroxide is at least 1.4 times the stoichiometric amount and the initial sodium hydroxide/water ratio in the medium of decomposition ranges from 1 to 40% by weight, whereby a precipitate of thorium hydroxide and rare earth hydroxides is produced, together with a solution of sodium fluoride, and then separating the NaF solution therefrom.Type: GrantFiled: November 28, 1988Date of Patent: September 4, 1990Assignee: Rhone-Poulenc ChimieInventors: Francinet Cailly, Frederic Fabre
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Patent number: 4941998Abstract: The invention is directed to a method of washing a solvent in the reprocessing of irradiated nuclear fuel. The solvent is washed with an aqueous solution in a mixer-settler having at least one stage which includes a mixing chamber and a settling chamber. The pH of the dispersion in the mixing chamber is measured and an amount of washing solution is added which influences the pH toward the desired operational value. An apparatus for carrying out the method is also disclosed.Type: GrantFiled: May 18, 1988Date of Patent: July 17, 1990Assignee: Deutsche Gesellschaft fur Wiederaufarbeitung von Kernbrennstoffen mbHInventors: Klaus Eiben, Heinz Evers
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Patent number: 4913884Abstract: This is an improvement to a process for making zirconium metal from uranium-containing zircon ore. The process being improved is of the type which utilizes a fluidized bed carbochlorination process of the zircon ore in which uranium chloride is volatilized at the ore chlorinator temperature and follows as an impurity in the zirconium-hafnium tetrachloride stream, and in which removal of iron impurities is performed by liquid-liquid iron extraction with methyl isobutyl ketone, and the zirconium-hafnium stream is further processed by a separations step to reduce the hafnium content to low levels by liquid-liquid hafnium extraction. The improvement comprises adding 1-9 weight percent quaternary ammonium halide (e.g. tricaprylmethylammonium chloride) to the methyl isobutyl ketone in the liquid-liquid iron extraction.Type: GrantFiled: November 9, 1988Date of Patent: April 3, 1990Assignee: Westinghouse Electric Corp.Inventor: Robert J. Feuling
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Patent number: 4871478Abstract: A process for the extraction of uranium and plutonium from spent nuclear fuels or breeder reactor materials. The spent nuclear fuels or breeder reactor materials are dissolved in nitric acid to provide an aqueous acid solution containing uranium, plutonium, neptunium, other transuranium elements, fission products, corrosion products, activation products and other contamination products. This aqueous acid solution is fed, as an aqueous phase, at a controllable flow rate into a liquid-liquid extraction apparatus also having an organic solvant phase flowing at a controllable rate. The organic phase contains an extraction agent. The temperature of solutions in the extraction apparatus and/or the concentration of the aqueous acid solution before the said aqueous acid solution is fed into the extraction apparatus, is adjusted to satisfy the following inequality: ##EQU1## where T.sub.E =the temperature of the solutions in the extractor (.degree.C.);U.sub.f =the uranium concentration of the feed solution (g/l);Pu.Type: GrantFiled: November 9, 1987Date of Patent: October 3, 1989Assignee: Kernforschungszentrum Karlsruhe GmbHInventors: Georg Petrich, Helmut Schmieder
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Patent number: 4867951Abstract: An organic extracting solution and an extraction method useful for separating elements of the actinide series of the periodic table from elements of the lanthanide series, where both are in trivalent form. The extracting solution consists of a primary ligand and a secondary ligand, preferably in an organic solvent. The primary ligand is a substituted monothio-1,3-dicarbonyl, which includes a substituted 4-acyl-2-pyrazolin-5-thione, such as 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione (BMPPT). The secondary ligand is a substituted phosphine oxide, such as trioctylphosphine oxide (TOPO).Type: GrantFiled: March 31, 1988Date of Patent: September 19, 1989Assignee: The United States of America as represented by the United States Department of EnergyInventors: Barbara F. Smith, Gordon D. Jarvinen, Robert R. Ryan
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Patent number: 4855081Abstract: A method 20 for decontaminating plastic products and materials which have become radioactively contaminated. The treatment method 20 involves dissolving such plastics in a dissolution tank 28 in an organic solvent and treating the resulting solution by a solvent extraction technique in column 36 to remove particulate and dissolved radioactive contaminants from the plastic. The contaminants can be buried in a low level radioactive waste site and the separated plastic material can be disposed of in a sanitary landfill or recycled into other plastic products.Type: GrantFiled: June 7, 1988Date of Patent: August 8, 1989Assignee: Nutech, Inc.Inventor: James M. Wallace
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Patent number: 4855080Abstract: A method 20 for decontaminating specially selected plastic materials comprised of polymers and copolymers of unsaturated organic acids and other specially selected plastic materials, which have become radioactively contaminated, includes dissolving such plastic materials in an aqueous solvent 34 and treating the resulting solution selectively via filtration 36, ion-exchange absorption 40, and precipitation 44 processes to remove particulate and dissolved radioactive contaminants. The treated aqueous stream may be discharged to a sewage stream and the separated plastic materials can be disposed of in a sanitary landfill or recycled into other plastic products.Type: GrantFiled: June 7, 1988Date of Patent: August 8, 1989Assignee: Nutech, Inc.Inventors: William J. McConaghy, James M. Wallace