Group Va Metal Or Arsenic (sb, Bi, Or As) Patents (Class 423/87)
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Publication number: 20010005495Abstract: A process for preparing a nanocrystalline material comprising at least a first ion and at least a second ion different from the first ion, and wherein at least the first ion is a metal ion, is described. The process comprises contacting a metal complex comprising the first ion and the second ion with a dispersing medium suitable to form the nanocrystalline material and wherein the dispersing medium is at a temperature to allow formation by pyrolysis of the nanocrystalline material when contacted with the metal complex.Type: ApplicationFiled: September 9, 1998Publication date: June 28, 2001Applicant: Paul O'BrienInventors: PAUL O'BRIEN, TITO TRINDADE
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Patent number: 6165426Abstract: Disclosed is a method of removing a soluble antimony compound from a liquid in which it is dissolved. The liquid is contacted with a hydrated compound, particularly a hydrated compound that forms carbonate ions, bicarbonate ions, or both in the liquid, such as carbonic acid or hydrates of sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, ammonium carbonate, or ammonium bicarbonate. An antimony compound is formed that is insoluble in the liquid and it is separated from the liquid.Type: GrantFiled: July 16, 1999Date of Patent: December 26, 2000Assignee: Occidental Chemical CorporationInventor: Sanjay K. Mandal
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Patent number: 6153155Abstract: The invention relates to a process for recovering the transition metal component of catalysts used in the hydroconversion of heavy hydrocarbonaceous materials. In accordance with the invention, a slurry of a transition metal catalyst and hydrocarbon is catalytically desulfurized resulting in a desulfurized product and a solid residue containing the transition metal. The transition metal may be recovered by coking the residue and then dividing the coker residue into two portions are combusted with the flue dust from the first combustion zone being conducted to the second combustion zone. The flue dust from the second combustion zone is treated with ammonia and ammonium carbonate in order to obtain ammonium molybdate.Type: GrantFiled: December 15, 1998Date of Patent: November 28, 2000Assignee: Exxon Research and Engineering CompanyInventors: Michael Y. Wen, Georgui S. Golovin, Mikhail Ja. Shpirt, Leonid A. Zekel, Andrew Sullivan, Stephen Mark Davis
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Patent number: 6153081Abstract: A method of recovering antimony and bismuth from copper electrolyte comprises the steps of immersing a pure copper material in the copper electrolyte, so that the iron ions are reduced from Fe.sup.3+ ions to Fe.sup.2+ ions, using a mixture of dilute sulfuric acid and sodium chloride adjusting the acidity or acidic concentration, to selectively elute the bismuth and antimony wherein if the final concentration of bismuth is adjusted to be 0.02 g/l or less in the bismuth election, it is possible to keep the maximum concentration of bismuth in the antimony eluate in the elution of antimony after selective bismuth elution to 0.01 g/l or less.Type: GrantFiled: January 11, 1996Date of Patent: November 28, 2000Inventors: Atsushi Fukui, Naoyuki Tsuchida, Kouji Ando
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Patent number: 6117209Abstract: A hydrometallurgical method involves treating a dross source containing typically both antimony and tin and treating the dross to a series of chemical operations to yield a soft lead precursor, suitable for making soft lead for lead-based alloys for batteries or other applications, which method includes utilizing sulfuric acid to decompose the dross source to provide a slurry in which the liquid contains the principal tin values and the solid phase contains the antimony and lead values, followed by treating of the separated solid phase so as to either separate the lead values from the antimony values via an antimony leach and a solid/liquid separation or by desulfurizing the solid phase, carrying out a solid/liquid separation, treating the solid phase with a lead leach to solubilize the lead values and carrying out a further solid/liquid separation to recover the lead-rich phase as the filtrate, separated from the antimony-rich solid phase.Type: GrantFiled: November 2, 1998Date of Patent: September 12, 2000Assignee: GNB Technologies, Inc.Inventor: Prosper K. Adanuvor
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Patent number: 6117333Abstract: A process is disclosed which involves removing hydrocarbons, arsenic and mercury from wastewater produced in oil and gas fields. An oxidant, ferric ions, and flocculent are sequentially added to the wastewater to form a removable sludge containing the arsenic, hydrocarbon, and mercury contaminants. The Oxidation-Reduction Potential of the wastewater is controlled by oxidant addition to allow the required arsenic oxidation to occur while maintaining the mercury in elemental form. The process requires relatively short residence times between chemical additions and provides for large wastewater throughputs. The cleaned wastewater is suitable for discharge to the environment.Type: GrantFiled: April 22, 1997Date of Patent: September 12, 2000Assignee: Union Oil Company of CaliforniaInventors: Theodore C. Frankiewicz, John Gerlach
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Patent number: 6113868Abstract: Tungstate solutions are purified by a precipitation process followed by two anion exchange processes to reduce molybdenum and arsenic impurity content. The precipitation involves acidification of the original highly basic tungstate solution to pH of 7 to 10 without addition of precipitating agents and separates out the bulk of impurities other than Mo, As. The first anion exchange process removes As. Then a remaining filtrate from the latter process is treated with sulfides to form thiomolybdates from impurity Mo content and the thiomolybdates are then separated out from the tungstate solution in a second anion exchange process.Type: GrantFiled: December 31, 1998Date of Patent: September 5, 2000Assignee: H. C. Starck GmbH & Co. KGInventors: Wolfgang Mathy, Wilfried Gutknecht
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Patent number: 6093328Abstract: Arsenic and TOC are removed from drinking water or wastewaters by use of finely-divided metallic iron in the presence of powdered elemental sulfur or other sulfur compounds such as manganese sulfide, followed by an oxidation step. A premix may be produced for this process, by adding the iron, sulfur and oxidizing agent to water in a predetermined pH range. The iron and sulfur are mixed for a period of time dependent upon the temperature and pH of the water and the presence of complexing or sequestering minerals and organic acids in the water. An oxidizing agent is added to the mixture and agitating is continued. In a preferred embodiment the oxidizing agent is hydrogen peroxide. Water is decanted from the mixture after a sufficient reaction time, to produce a concentrated premix. This premix can be added to water intended for drinking or to industrial effluents containing toxic materials.Type: GrantFiled: February 1, 1999Date of Patent: July 25, 2000Inventor: Peter F. Santina
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Patent number: 6090353Abstract: A process for removing impurities contained in the crystal lattice of minerals, comprising the steps of forming a mixture of a mineral capable of structurally reorganizing its crystal lattice which contains an impurity in its crystal lattice and a halogen anion, and water; heating the mixture to the mineral's structural reorganization transition temperature; holding the mixture at the structural reorganization transition temperature for a sufficient period of time to allow the impurity to freely migrate from the lattice to combine with the halogen anion; and separating the combined impurity and anion from the mixture to render the mineral essentially free of the impurity. The process is applicable to numerous minerals and impurities, but is especially useful to remove arsenic from fluorspar. Numerous halogen anions can be employed, such as chlorides, fluorides, bromides and iodides, but the preferred halogen anion is a metal chloride such as calcium chloride.Type: GrantFiled: April 1, 1998Date of Patent: July 18, 2000Assignee: Svedala Industries, Inc.Inventors: Bobby P. Faulkner, John M. Paustian
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Patent number: 6030433Abstract: A method for extracting metals from metal-containing materials, especially waste, by pyrohydrolysis. The metal-containing materials which contain at least one or more of the metals from the group consisting of Zn, Cd, Pb, Hg, Cu, Sn (as Sn(0) and Sn(II)), As, Sb, Au, Ag and Bi, are made to react at 700-1100.degree. C., advantageously 800-900.degree. C., with a gas composition which at least comprises 25-45% by volume of water vapor, 0-12% by volume of carbon dioxide, 2-20% by volume of hydrogen chloride, 0-15% by volume of carbon monoxide, the remainder being nitrogen and possibly oxygen. The metals from the above-mentioned group are extracted in the form of volatile metal chlorides.Type: GrantFiled: February 5, 1997Date of Patent: February 29, 2000Assignee: Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek (TNO)Inventors: Hendrik Jan Luggenhorst, Edgar Manfred Lawrence Peek
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Patent number: 5989430Abstract: In a method for recovering antimony from the electrolyte of copper electro-refining process, the antimony is adsorbed on the chelating resin and is then eluted by acid. The eluate is then neutralized to recover antimony. In a conventional method, a large amount of acid and alkali is used. In the inventive eluting method, the antimony concentration in the acidic eluting solution is adjusted to 4 g/L or more in the first step and 3 g/L or less in the second step.Type: GrantFiled: June 30, 1998Date of Patent: November 23, 1999Assignee: Nippon Mining & Metals Co., Ltd.Inventors: Kazuhiko Motoba, Katutoshi Narita
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Patent number: 5972073Abstract: The present invention is directed to a method for separating the group III element component of a group III-V material from an aqueous waste containing a group III-V material to allow for their recovery and beneficial use. The method includes adjusting the pH of an aqueous waste containing a group III-V material to a pH from about 9.5 to about 12.5 by adding an alkali metal hydroxide base to the aqueous waste; precipitating a group V element oxyanion by adding a soluble alkaline metal salt to the aqueous waste; separating the group V element oxyanion from the aqueous waste; adjusting the pH of the aqueous waste to form a group III element hydroxide precipitate by adding a mineral acid to the aqueous waste; separating the group III element hydroxide precipitate from the aqueous waste; and recovering the group III element from the group III element hydroxide precipitate.Type: GrantFiled: October 2, 1997Date of Patent: October 26, 1999Assignee: The University of DaytonInventors: Jeffrey Allen Sturgill, Joseph Thomas Swartzbaugh
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Patent number: 5961940Abstract: Disclosed is a method of pretreating sulphide ores or sulphide ore concentrates having high bismuth contents that have a disturbing influence on further processing of the ores or concentrates, such as to enable the ores or concentrates to be further processed for the recovery of their valuable metal contents or at least to facilitate such processing. The method is characterized by leaching the ore or the concentrate with sulfuric acid over a predetermined time period while supplying heat at a pH below 2, and thereafter separating from the leachate a leaching residue in the form of a product which is leaner in bismuth and more enriched with regard to its valuable metal content than the input material.Type: GrantFiled: March 23, 1998Date of Patent: October 5, 1999Assignee: Boliden ABInventors: .ANG.ke Sandstrom, Jan-Erik Sundkvist
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Patent number: 5874374Abstract: A method for producing engineered materials from salt/polymer aqueous solutions in which an aqueous continuous phase having at least one metal cation salt is mixed with a hydrophilic organic polymeric disperse phase so as to form a metal cation/polymer gel. The metal cation/polymer gel is then treated to form a structural mass precursor, which structural mass precursor is heated, resulting in formation of a structural mass having predetermined characteristics based upon the intended application of the structural mass.Type: GrantFiled: September 8, 1997Date of Patent: February 23, 1999Assignee: Institute of Gas TechnologyInventor: Estela Ong
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Patent number: 5866014Abstract: Arsenic and TOC are removed from drinking water or wastewaters by use of finely-divided metallic iron in the presence of powdered elemental sulfur or other sulfur compounds such as manganese sulfide, followed by an oxidation step. A premix may be produced for this process, by adding the iron, sulfur and oxidizing agent to water in a predetermined pH range. The iron and sulfur are mixed for a period of time dependent upon the temperature and pH of the water and the presence of complexing or sequestering minerals and organic acids in the water. An oxidizing agent is added to the mixture and agitating is continued. In a preferred embodiment the oxidizing agent is hydrogen peroxide. Water is decanted from the mixture after a sufficient reaction time, to produce a concentrated premix. This premix can be added to water intended for drinking or to industrial effluents containing toxic materials.Type: GrantFiled: November 4, 1996Date of Patent: February 2, 1999Inventor: Peter F. Santina
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Patent number: 5820966Abstract: The process provides a method of removing arsenic from solutions containing sulfur dioxide in an environmentally acceptable manner. This process first oxidizes arsenic, iron and sulfur dioxide contained in an aqueous solution to prepare the solution for precipitation and to improve process control. Recycled neutralized precipitate seeds the oxidized aqueous solution. A calcium-containing base precipitates products of neutralization on the seeds. The final neutralized precipitate contains a stable ferric arsenate compounds.Type: GrantFiled: December 9, 1997Date of Patent: October 13, 1998Assignee: Inco LimitedInventors: Eberhard Krause, Yoshiaki Okita, Reichel Abelis Tenbergen, Brian Charles Blakely, Justin Raskauskas
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Patent number: 5788913Abstract: Solution precipitation processes for preparing antimony doped tin oxide having improved volumetric efficiency and improved wash efficiency involving use of concentrated base and metal salt solutions are disclosed.Type: GrantFiled: November 1, 1996Date of Patent: August 4, 1998Assignee: E. I. du Pont de Nemours and CompanyInventor: Donald Keith Swanson
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Patent number: 5766512Abstract: The object of the invention is to provide a zinc antimonate anhydride and a production method thereof. The invention relates to a particle having a ZnO/Sb.sub.2 O.sub.5 molar ratio in a range of from 0.8 to 1.2, a crystal structure of zinc antimonate anhydride (Znsb.sub.2 O.sub.6), and a primary particle size in a range of from 5 to 500 nm. The production method of these particles comprises the steps of mixing a zinc compound with a colloidal antimony oxide at a ZnO/Sb.sub.2 O.sub.5 molar rate in a range of from 0.8 to 1.2, followed by calcining the mixture within a temperature range of from 500.degree. to 1100.degree. C. The particles of this invention are applicable as a flame retardant for plastics, a smoke suppressant, antistatic agent for plastics and glasses, and resistor.Type: GrantFiled: December 3, 1996Date of Patent: June 16, 1998Assignee: Nissan Chemical Industries, Ltd.Inventors: Yoshitane Watanabe, Keitaro Suzuki, Yoshinari Koyama
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Patent number: 5762891Abstract: The present invention is a method to remove arsenic from arsenic-containing materials, such as an ore or concentrate, by roasting the arsenic-containing material to convert arsenic sulfides into arsenic oxides. The arsenic oxides are contained in the roasted arsenic-containing material. The roasted arsenic-containing material is contacted with a lixiviant to solubilize the arsenic in the oxide in a pregnant leach solution. Ferric arsenate, an environmentally stable compound, is formed in the lixiviant. The ferric arsenate can be removed to provide a treated solution complying with environmental regulations. The method provides a simple and effective technique for removing arsenic from arsenic-containing materials.Type: GrantFiled: February 27, 1996Date of Patent: June 9, 1998Assignee: Hazen Research, Inc.Inventors: Jerome P. Downey, Harry Mudgett
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Patent number: 5736071Abstract: The invention relates to a double oxide which is transparent and electrically conductive. This double oxide has a defective fluorite crystal structure and is represented by a formula of In.sub.3 Sb.sub.1-X O.sub.7-.delta. where X is in a range of from about -0.2 to about 0.2, and .delta. is in a range of from about -0.5 to about 0.5. The double oxide is good in electric conductivity and high in visible light transmittance, in particular in short wavelength region of visible light, as compared with conventional oxide materials.Type: GrantFiled: January 16, 1997Date of Patent: April 7, 1998Assignee: Central Glass Company, LimitedInventor: Keiji Sato
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Patent number: 5707552Abstract: The object of the invention is to provide a zinc antimonate anhydride and a production method thereof. The invention relates to a particle having a ZnO/Sb.sub.2 O.sub.5 molar ratio in a range of from 0.8 to 1.2, a crystal structure of zinc antimonate anhydride (Znsb.sub.2 O.sub.6), and a primary particle size in a range of from 5 to 500 nm. The production method of these particles comprises the steps of mixing a zinc compound with a colloidal antimony oxide at a ZnO/Sb.sub.2 O.sub.5 molar rate in a range of from 0.8 to 1.2, followed by calcining the mixture within a temperature range of from 500.degree. to 680.degree. C. The particles of this invention are applicable as a flame retardant for plastics, a smoke suppressant, antistatic agent for plastics and glasses, and resistor.Type: GrantFiled: September 11, 1996Date of Patent: January 13, 1998Assignee: Nissan Chemical Industries, Ltd.Inventors: Yoshitane Watanabe, Keitaro Suzuki, Yoshinari Koyama
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Patent number: 5698483Abstract: A process for producing nano size powders comprising the steps of mixing an aqueous continuous phase comprising at least one metal cation salt with a hydrophilic organic polymeric disperse phase, forming a metal cation salt/polymer gel, and heat treating the gel at a temperature sufficient to drive off water and organics within the gel, leaving as a residue a nanometer particle-size powder.Type: GrantFiled: March 17, 1995Date of Patent: December 16, 1997Assignee: Institute of Gas TechnologyInventors: Estela T. Ong, Vahid Sendijarevic
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Patent number: 5688378Abstract: The invention relates to methods and processes for the photoassisted oxidation of dissolved species such as arsenic, iron, phosphorous and sulphur. Each aspect of the invention involves supplying to a solution including the species to be oxidized, an oxidant and a photoabsorber, and then irradiating the resultant solution with UV/electromagnetic radiation. The resulting oxidised species can then be subsequently treated, used and/or removed (e.g. through precipation/co-precipitation).Type: GrantFiled: April 22, 1996Date of Patent: November 18, 1997Assignee: CRC for Waste Management & Pollution ControlInventors: Ging Hauw Khoe, Maree Therese Emett, Robert G. Robins
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Patent number: 5670434Abstract: Process for preparing a high-T.sub.c superconductor as a precursor material for the oxide-powder-in-tube method (OPIT). The present invention relates to a process for preparing a high-T.sub.c superconductor as a precursor material for the oxide-powder-in-tube method, which involves mixing the oxides of the elements Bi, Sr, Ca and Cu and completely melting them at temperatures of >1000.degree. C., then casting the melt onto a substrate which is kept at room temperature, and disintegrating the cooled melt block and grinding it into a powder.Type: GrantFiled: January 30, 1996Date of Patent: September 23, 1997Assignee: Hoechst AktiengesellschaftInventors: Marc Neubacher, Joachim Bock, Christoph Lang, Eberhard Preisler, Helga Weis
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Patent number: 5632963Abstract: A process is disclosed for removing impurity elements, such as arsenic, and if necessary antimony, iron or bismuth, from valuable metal containing, such as copper containing, strongly mineral acid solutions by way of solvent extraction with organic solutions of hydroxamic acids, and for selectively stripping the impurity elements therefrom. Antimony, iron or bismuth are stripped with complexing acids, and arsenic is stripped with an aqueous solution containing valuable metal ions at a pH value in the 1.5 to 5 range, a higher pH than the original valuable metal containing aqueous acid solution.Type: GrantFiled: October 19, 1994Date of Patent: May 27, 1997Assignee: Henkel Kommanditgesellschaft auf AktienInventors: Werner Schwab, Ralf Kehl
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Patent number: 5618503Abstract: A method of preparing antimony pentafluoride comprising converting antimony compounds to hydroxonium fluoroantimonates by reaction of the antimony compounds with fluorinating material, such as hydrogen fluoride, in the presence of an oxidizing agent, such as hydrogen peroxide, removing water from the reaction product to concentrate the hydroxonium fluoroantimonates and reacting the hydroxonium fluoroantimonates with carbonyl difluoride to produce antimony pentafluoride. In one embodiment the hydroxonium fluoroantimonates are prepared by recovering the antimony from spent alkylation catalyst comprising SbF.sub.5 deposited on silica. The silica can also be recovered and recycled to produce a remanufactured alkylation catalyst.Type: GrantFiled: June 28, 1996Date of Patent: April 8, 1997Assignee: Chemical Research & Licensing CompanyInventors: Alan Johnson, H. J. Woods, H. J. Connor
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Patent number: 5575919Abstract: Arsenic and TOC are removed from drinking water or wastewaters by use of finely-divided metallic iron in the presence of powdered elemental sulfur or other sulfur compounds such as manganese sulfide, followed by an oxidation step. A premix may be produced for this process, by adding the iron, sulfur and oxidizing agent to water in a predetermined pH range. The iron and sulfur are mixed for a period of time dependent upon the temperature and pH of the water and the presence of complexing or sequestering minerals and organic acids in the water. An oxidizing agent is added to the mixture and agitating is continued. In a preferred embodiment the oxidizing agent is hydrogen peroxide. Water is decanted from the mixture after a sufficient reaction time, to produce a concentrated premix. This premix can be added to water intended for drinking or to industrial effluents containing toxic materials.Type: GrantFiled: December 8, 1994Date of Patent: November 19, 1996Assignee: Peter F. SantinaInventor: Peter F. Santina
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Patent number: 5573739Abstract: The present invention is concerned with a process for selectively removing antimony, bismuth, or both, from acidic solution by submitting the solution to oxidizing conditions thereby causing the selective precipitation of antimony and bismuth; filtering precipitated antimony and bismuth; and submitting the oxidized solution to reducing conditions before it is returned to the electrorefining cell.Type: GrantFiled: October 28, 1994Date of Patent: November 12, 1996Assignee: Noranda, Inc.Inventors: Viken P. Baboudjian, Jack S. Stafiej
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Patent number: 5547588Abstract: A process for treatment of hazardous liquid waste comprising trace amounts of hazardous elements in solution as oxyanions by oxyanion fixation within ettringite and related minerals. In accordance with the disclosed process, reagents for forming ettringites are mixed with the waste stream resulting in the formation of oxyanion-substituted ettringite and related materials. The resulting ettringite and related minerals are separated by filtration from the liquid. Thereafter, the liquid, having an elevated pH, is neutralized by carbon dioxide sparging resulting in precipitation of excess reagents in the liquid. Thereafter, the precipitates are filtered, producing a clean liquid.Type: GrantFiled: October 25, 1994Date of Patent: August 20, 1996Assignee: Gas Research InstituteInventors: David J. Hassett, Jeffrey S. Thompson
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Patent number: 5545800Abstract: A reduction method is provided for the treatment of arsenic-containing organic compounds with simultaneous recovery of pure arsenic. Arsenic-containing organic compounds include pesticides, herbicides, and chemical warfare agents such as Lewisite. The arsenic-containing compound is decomposed using a reducing agent. Arsine gas may be formed directly by using a hydrogen-rich reducing agent, or a metal arsenide may be formed using a pure metal reducing agent. In the latter case, the arsenide is reacted with an acid to form arsine gas. In either case, the arsine gas is then reduced to elemental arsenic.Type: GrantFiled: July 21, 1994Date of Patent: August 13, 1996Assignee: Regents of the University of CaliforniaInventors: Ravindra S. Upadhye, Francis T. Wang
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Patent number: 5501767Abstract: Silicon is employed as a reducing agent in an acid bath to adsorb noble metals present as contaminants in the acid. In the manufacture of silicon devices for electronic memory and other devices, polonium-210 is adsorbed by silicon getters to reduce soft error rate attributable to alpha particle emissions from the radioactive polonium. The noble metals in addition to polonium which can be plated onto silicon using the disclosed method are gold, silver, platinum, copper, palladium, mercury, selenium and bismuth.Type: GrantFiled: November 13, 1992Date of Patent: March 26, 1996Assignee: Micron Technology, Inc.Inventors: Troy Sorensen, Eric Grieger
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Patent number: 5498398Abstract: Disclosed herein is a method for treating a spent copper-refining electrolyte to remove impurities such as copper (Cu), arsenic (As), antimony (Sb), bismuth (Bi), nickel (Ni) and the like by using a hydrogen sulfide gas. The method comprises the steps of: (a) blowing a hydrogen sulfide gas into the spent electrolyte to precipitate copper sulfide (CuS); (b) blowing air into the coprecipitates solution obtained in the above step (a) to oxidize arsenic, bismuth and antimony thereby redissolving them into the solution, and the solution is subjected to solid-liquid separation to separate copper sulfide from the liquid; (c) blowing a sulfur dioxide gas into the copper-depleted liquid to reduce arsenic, bismuth and antimony and blowing a nitrogen gas to purge the remaining sulfur dioxide gas; (d) blowing a hydrogen sulfide gas to precipitate arsenic, bismuth and antimony in the form of sulfides and blowing a nitrogen gas to purge the remaining hydrogen sulfide gas and separating arsenic sulfide (As.sub.2 S.sub.Type: GrantFiled: November 4, 1994Date of Patent: March 12, 1996Assignee: Lucky Metals CorporationInventors: Seong W. Kang, Yong H. Lee
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Patent number: 5494652Abstract: A fine metal oxide powder is prepared by a method comprising the steps of (1) preparing a hydroxide precursor of a metal oxide, (2) mixing the precursor with an inorganic compound having a melting point lower than the crystallization temperature of the metal oxide, and (3) subjecting the resulting mixture to a high temperature thermal treatment to form the fine metal oxide powder.Type: GrantFiled: March 23, 1994Date of Patent: February 27, 1996Assignee: Eastman Kodak CompanyInventor: Jean C. Robert
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Patent number: 5482534Abstract: A process suitable for the extraction or recovery of metal values from arsenic containing feeds and including the steps of: a) treating the feed with a nitric acid-containing leachant solution in order to dissolve the desired metals; b) adding a source of iron (III) to the leachant solution whereby to oxidise arsenic (III) in solution to arsenic (V); c) adding a neutralising agent to the leachant solution whereby to precipitate arsenic as arsenic (V); d) separating the arsenic (V) precipitate from the leachant solution; and e) recording metal values from the leachant solution.Type: GrantFiled: April 20, 1994Date of Patent: January 9, 1996Assignee: Sasox Processing Pty. LimitedInventors: Rodney L. Leonard, John G. Whellock
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Patent number: 5458867Abstract: A process for producing bismuth telluride including dissolving tellurium to form a first solution; heating the first solution to approximately 70.degree. C.; stirring the first solution; slowly and quantatively adding an amount of bismuth trioxide (Bi.sub.2 O.sub.3) to produce a Bi/Te second solution wherein the ratio of Bi: Te=2:3; cooling the second solution to approximately 25.degree. C.; preparing a solution of concentrated aqueous ammonia and distilled water; adding the solution of aqueous ammonia and distilled water dropwise to the second solution at approximately 25.degree. C. to form a third solution; rapidly stirring the third solution to produce a precipitate therefrom; separating the precipitate from the third solution by centrifugation; washing the separated precipitate in distilled water; drying the washed precipitate in air to produce a Bi.sub.2 Te.sub.3 O.sub.9.xH.sub.2 O, where x=1, precursor powder; heating predetermined quantities of the dried precursor powder to 250.degree. C.-275.degree.Type: GrantFiled: September 9, 1994Date of Patent: October 17, 1995Assignee: The United States of America as represented by the Secretary of CommerceInventor: Joseph J. Ritter
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Patent number: 5449660Abstract: A method of producing a compound oxide of elements including at least one of thallium, bismuth, lead, antimony, yttrium, each of rare earth elements, each of transition metal elements, each of alkali metal elements and each of alkaline earth metal elements. The method is comprised of the steps of (i) reacting at least one of carbonate, basic carbonate, hydroxide and co-precipitates of each of the above-mentioned elements with an amount of citric acid that is less than the weight equivalent of citric acid needed to form a completely citrated compound, and (ii) calcining the partly citrated compound. The co-precipitate can be one of a carbonate, a basic carbonate and a hydroxide of each of the above-mentioned elements.Type: GrantFiled: March 16, 1993Date of Patent: September 12, 1995Assignees: Nissan Motor Co., Ltd., Seimi Chemical Company, LimitedInventors: Fumio Munakata, Mitsugu Yamanaka, Susumu Hiyama
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Patent number: 5449503Abstract: The present invention provides a process for recovering arsenic acid from a starting mixture comprising sulfuric and arsenic acids and water. In step (a), the starting mixture is treated with a sulfur (IV) compound which will reduce the arsenic acid to arsenic (III) compound under conditions sufficient to substantially convert the arsenic acid to arsenic (III) wherein the resulting mixture comprises arsenic (III) compound, the sulfur (IV) compound, sulfuric acid, and water. In step (b), the resulting mixture is purged with gas to substantially remove the sulfur (IV) compound from the mixture wherein the purged mixture comprises the arsenic (III) compounds, sulfuric acid, and water. In step (c), the purged mixture is treated under conditions sufficient to substantially separate the arsenic (III) compounds from the purged mixture.Type: GrantFiled: August 26, 1994Date of Patent: September 12, 1995Assignee: AlliedSignal Inc.Inventors: Charles L. Redmon, Somanahalli N. Subbanna, Robert A. Smith
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Patent number: 5437849Abstract: To process vanadium-containing residues, the residues are leached in an aqueous slurry with introduction of SO.sub.2, the undissolved solids are removed. To effect a processing which is simple, economical and ecologically satisfactory, vanadium content is precipitated as a tetravalent vanadium compound from the sulfate solution at a pH from 7 to 9 by an addition of alkali metal hydroxide and the precipitate is removed from the alkali metal sulfate solution.Type: GrantFiled: May 20, 1993Date of Patent: August 1, 1995Assignee: Metallgesellschaft AktiengesellschaftInventor: Wolfgang Fennemann
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Patent number: 5419986Abstract: A method of making a rechargeable battery electrode material containing manganese oxide is provided. The method includes preparing an aqueous solution of manganese nitrate and dissolving bismuth nitrate into the solution. The mixture is heated to evaporate the water contained in the mixture and is further heated to facilitate decomposition of the nitrates in the mixture to form a compound containing manganese oxide and bismuth oxide. The compound is maintained at a temperature of between about 200 to 300 degrees Celsius for an additional 12 hours. Thereafter, the compound is cooled and ground to a desired particle size for use as a rechargeable battery electrode material. The compound may alto be mixed with commercially prepared electrolytic or chemical manganese dioxide to obtain a highly rechargeable battery electrode material. A related battery cell is also disclosed.Type: GrantFiled: October 15, 1993Date of Patent: May 30, 1995Assignee: Rechargeable Battery CorporationInventors: Ramesh C. Kainthla, David J. Manko, A. John Appleby
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Patent number: 5415847Abstract: A chemical process for treating pit waste contaminated with chromated copper arsenate (i.e. CCA). CCA is recovered for recycling, and remaining solids are decontaminated for safe disposal. Pit wastes are pulverized and reacted with concentrate sulfuric or phosphoric acid. Wood particles are partially decomposed and approximately 60% to 70% of the CCA is leached out. The acid-treated mixture is centrifuged or filtered to separate liquids from solids. Liquids are recycled for reuse in the CCA process. CCA-bearing solids enter a heated digester equipped with an air or water cooled condenser. Concentrated nitric and sulfuric acids are inputted into the digester and the ratio of nitric acid to sulfuric acid to solids is approximately six to two to one by volume. Nitric acid completely oxidizes all organic matter in the solids. Sulfuric acid serves as a dehydrating agent and liquid media for CCA. The initial oxidation is carried out at a temperature greater than 70.degree. C. and less than 100.degree. C.Type: GrantFiled: June 22, 1993Date of Patent: May 16, 1995Assignee: Gem, Inc.Inventor: Marguerite Robinson
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Patent number: 5378328Abstract: A process is provided for the recovery of bismuth from an ion exchange eluent solution consisting of at least 50% sulfuric acid maintained at a temperature of 95.degree.-100.degree. C. The process comprises the step of electrowinning bismuth from the sulfuric acid solution in an electrochemical cell at a current density up to 30 A/m.sup.2 using an insoluble anode and a cathode that is impervious to the highly corrosive environment of hot sulfuric acid, for a time interval such as to reduce the bismuth content of the solution down to about 3-5 g/L.Type: GrantFiled: August 4, 1993Date of Patent: January 3, 1995Assignee: Noranda Inc.Inventors: Varujan Baltazar, John L. Cromwell
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Patent number: 5366715Abstract: The present invention is concerned with a method for selectively removing antimony and bismuth from an impure sulphuric acid solution containing at least 50 g/L of acid and some concentration of ferric ion (for example copper refinery electrolyte), is disclosed. The method involves contacting the impure solution with a sufficient quantity of finely divided metallic copper so as to prereduce all ferric ion present in the solution to the ferrous oxidation state. The prereduced solution is then contacted with a chelating resin. The method avoids the deleterious loading of ferric iron onto the ion exchange resin and prevents the return of excessive amounts of chloride ion with the purified electrolyte.Type: GrantFiled: October 19, 1993Date of Patent: November 22, 1994Assignee: The University of British ColumbiaInventors: David B. Dreisinger, Brenna J. Y. Leong
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Patent number: 5348662Abstract: In the process of removing heavy metals from aqueous solutions (groundwater) by precipitation of a salt thereof, an oxidizing agent is optionally used to increase the valence of said metal, and a precipitation-enhancing agent is added to maximize particle size of the precipitate and to facilitate its separation from said solution.Type: GrantFiled: May 13, 1993Date of Patent: September 20, 1994Assignee: Elf Atochem North America, Inc.Inventors: Jeffrey H. Yen, Richard C. Spung
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Patent number: 5338460Abstract: A process is disclosed for the removal of dissolved heavy metals from aqueous solution contaminated therewith wherein at least one of said heavy metals is reacted with a water-soluble inorganic sulfide or hydrosulfide at a defined elevated temperature and a controlled pH of between about 2 to about 3.5 to thereby precipitate heavy metal sulfide, and thereafter separating the precipitate from the filtrate.Type: GrantFiled: April 22, 1993Date of Patent: August 16, 1994Assignee: Elf Atochem North America, Inc.Inventor: Jeffrey H. Yen
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Patent number: 5316683Abstract: Process for extracting Ge, Ga, In, As, Sb, Bi, Pt, Pd, Ni, and/or Co from an acid aqueous solution, wherein use is made of a resin with 8-hydroxyquinoline groups, resulting from the reaction of an aminated resin with an aldehyde and 8-hydroxyquinoline, characterized in that the aminated resin itself is obtained by imidoalkylation of a cross-linked styrene-copolymer and an ester or an ether of an N-hydroxyalkylimide and by hydrolysis of the imidoalkylation product.Type: GrantFiled: October 8, 1992Date of Patent: May 31, 1994Assignee: n.v. Union Miniere s.a.Inventors: Guy G. Haesebroek, Achille J. De Schepper
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Patent number: 5302360Abstract: A method for working up antimony halide catalysts containing inactivating organic impurities having high boiling points, in which anhydrous antimony trichloride can be isolated in a technically simple manner. The antimony trichloride can be chlorinated to obtain antimony pentachloride which can be re-used as a catalyst in a fluorination process.Type: GrantFiled: December 14, 1992Date of Patent: April 12, 1994Assignee: Kali-Chemie AGInventors: Guenter Fernschild, deceased, Sarah Fernschild, heir
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Patent number: 5290338Abstract: An antimony recovery process is disclosed in which antimony-containing material is leached in a solvent including elemental sulfur and a caustic to preferentially leach antimony. The antimony-containing leach liquor from the leaching step is separated from the insoluble residue by filtration, and the antimony compounds in the separated leach liquor are crystallized to separate the antimony compounds from impurities which are left in solution in the leach liquor. The crystals are then redissolved and treated to create marketable antimony products of high purity, such as antimony metal, sodium hydroxy antimonate, sodium antimonate, antimony pentoxide, and antimony pentasulfide. Alternatively, the crystallized antimony compounds comprising primarily sodium thioantimonate crystals may be recovered and sold without further treatment. Waste products may be treated with soluble iron compounds and lime to render the waste products safe for disposal.Type: GrantFiled: October 16, 1992Date of Patent: March 1, 1994Assignee: Sunshine Mining CompanyInventors: Corby G. Anderson, Suzzann M. Nordwick, Leo E. Krys
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Patent number: 5290528Abstract: An invention for removing arsenic from contaminated soil is described. The process of this invention involves contacting contaminated soil with a carbonated solution either formed by bubbling carbon dioxide through water or dissolving in alkali metal carbonate in water for contact of the contaminated soil. The supernatent solution resulting can then be treated to remove the arsenic, preferably with reverse osmosis, for further use of the water and the decontaminated soil returned to the environment.Type: GrantFiled: February 12, 1992Date of Patent: March 1, 1994Assignee: Texas Romec, Inc.Inventors: Mark A. O'Connor, Rodney J. O'Connor
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Patent number: 5264191Abstract: A quaternary ammonium trihalide, a novel compound, represented by the formula:[A--R'].sup.+ .multidot.X.sub.3.sup.-(wherein A stands for a trialkyl-amino radical or a pyridyl radical, R' for an alkyl radical of 6 to 22 carbon atoms, and X for a halogen atom) and a method for the dissolution of a metal with a liquid consisting essentially of an organic solvent and the quaternary ammonium trihalide.Type: GrantFiled: May 22, 1992Date of Patent: November 23, 1993Assignees: Agency of Industrial Science and Technology, Ministry of International Trade and IndustryInventors: Yukimichi Nakao, Kyoji Kaeriyama
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Patent number: 5262063Abstract: In the process of removing heavy metals from aqueous solutions by precipitation of a salt thereof at increased pH, multiple stage precipitation by upward stepwise pH adjustment and solid separation at each stage is used to facilitate the manufacture of a product of high purity.Type: GrantFiled: May 14, 1992Date of Patent: November 16, 1993Assignee: Elf Atochem North America, Inc.Inventor: Jeffrey H. Yen