Abstract: The present invention relates to an electrowinning cell adapted to recover metal ions from a solution as their corresponding elementary metals. The electrowinning cell includes a reservoir and a filter in fluid communication with the reservoir. The filter is operative to receive a solution containing metal ions from a location proximate to the cathode and to retain a first portion of the solution having a first concentration of metal ions and to remove a second portion of the solution having a second concentration of metal ions lower than the first concentration. The electrowinning cell additionally includes return means operative to return the first portion of the solution to the reservoir. The present invention also relates to a method of concentrating metal ions in a solution for use in an electrochemical cell and to a system for reducing metal ions in a solution to their corresponding elementary metals.
Abstract: A low temperature alkali metal electrolysis process is provided. The process comprises carrying out the electrolysis in the presence of a co-electrolyte and an alkali metal halide. The co-electrolyte comprises (1) a nitrogen-containing compound and optionally one ore more Group IB halides, Group IIIA halides, Group VIII halides; (2) a Group IIIA halide, a Group VB halide, or combinations of a Group IIIA halide and a Group VB halide; or (3) water. Also provided is a low temperature electrolysis process, which comprises carrying out the process using a cathode that comprises (1) a liquid alkali metal; (2) an alloy of two or more metals selected from the group consisting of bismuth, lead, tin, antimony, indium, gallium, thallium, and cadmium; or (3) an electrically conductive liquid solvated alkali metal.
Type:
Grant
Filed:
January 14, 2002
Date of Patent:
May 4, 2004
Assignee:
E. I. du Pont de Nemours and Company
Inventors:
Jeffery S. Thompson, Howard M. Blank, Walter John Simmons, Oswald Robert Bergmann
Abstract: Device (1) to conduct current to or from the electrodes of an electrolysis cell, which device in the direction towards the electrolysis cell comprises three types of segments; at least one outer segment (2) joined with at least one intermediate segment (3) which again is joined with at least one inner segment (4); where the outer segment (2) has at least one end (5) which is to/shall extend out from an electrode body (6) towards an outer current circuit, and the outer segment is coupled to at least one intermediate segment (3) which again is coupled to at least one inner segment with at least one section (4) or end (7) in the electrode body; where the inner segment (4) is manufactured from steel, the intermediate segment is manufactured with a steel lining (8) over an inner core of a material (9) with better electrical and thermal conductivity than steel, and the outer segment is manufactured from a material (9) with better electrical and thermal conductivity than steel.
Abstract: A method of electrochemically reducing a metal oxide to the metal in an electrochemical cell is disclosed along with the cell. Each of the anode and cathode operate at their respective maximum reaction rates. An electrolyte and an anode at which oxygen can be evolved, and a cathode including a metal oxide to be reduced are included as is a third electrode with independent power supplies connecting the anode and the third electrode and the cathode and the third electrode.
Abstract: A galvanic cell system (50) in fluid communication with a dewatering system (40) of an inhibited oxidation scrubber (20) removes an oxidation catalyst, i.e., solution phase iron (98), from the process liquor (42) produced by the dewatering system (40) and replaces the iron (98) with magnesium (104) in an oxidation-reduction reaction. An electrolytic cell system (154) in fluid communication with a dewatering system (144) of a forced oxidation scrubber (128) removes an oxidation inhibitor, i.e., solution phase aluminum (174), from the process liquor (146) produced by the dewatering system (144) and replaces the aluminum (174) with iron (170) in an oxidation-reduction reaction. The process liquor (42, 146) is subsequently returned to the scrubber (20, 128) with the solution phase metal (98, 174) selectively removed, thereby enhancing the scrubbing efficiency of the scrubber (20, 128).
Type:
Grant
Filed:
July 10, 2001
Date of Patent:
February 3, 2004
Assignee:
Pinnacle West Capital Corporation
Inventors:
Bruce A. Salisbury, Kelly L. Baird, Calvin C. Webb
Abstract: The present invention relates to a method for treating spent tin or tin/lead stripping solution used in the electronic industry, particularly in the manufacture of printed circuit boards or a lead frames. Said method comprises (i) electrolytically reducing copper ions in the solution to copper at a low temperature; (ii) electrolytically oxidizing Sn2+ and Pb2+ in the solution at a high temperature to form solid tin and lead oxides and hydroxides; (iii) separating solid tin and lead oxides and hydroxides from the solution; (iv) dissolving tin and lead oxides and hydroxides obtained in step (iii) in a strong alkali or acidic solution; and (v) electrolytically reducing the alkali or acidic solution obtained in step (iv) at a high temperature to recover metallic tin and lead. Also, the filtrate obtained in step (iii) above is useful for preparing fresh tin or tin/lead stripping solution.
Type:
Grant
Filed:
April 26, 2002
Date of Patent:
February 3, 2004
Assignees:
Amia Co., Ltd., Persee Chemical Co., Ltd.
Abstract: A process for purification of molten salt electrolytes containing magnesium chloride in which oxygen-containing impurities such as magnesium hydroxychloride are destroyed both electrolytically and chemically. The process comprises passing a direct current through a magnesium chloride-containing molten salt electrolyte, thereby electrolyzing a portion of the oxygen-containing impurities at the anode. In addition, the voltage and current of the direct current are sufficiently high to cause electrolysis of a small proportion of the magnesium chloride present in the electrolyte to thereby produce finely dispersed droplets of elemental magnesium in the electrolyte. The droplets of elemental magnesium react chemically with oxygen-containing impurities present in the electrolyte. The purified electrolyte is transferred to an electrolytic cell for the production of magnesium metal and chlorine gas.
Type:
Grant
Filed:
July 18, 2001
Date of Patent:
January 13, 2004
Assignee:
Hatch Associates Ltd.
Inventors:
Roger C. Urquhart, Roman Deshko, Sami Mourad
Abstract: The present invention is directed to a process for recovering metal values from metal-bearing materials. During a reactive process, a seeding agent is introduced to provide a nucleation site for the crystallization and/or growth of solid species which otherwise tend to passivate the reactive process or otherwise encapsulate the metal value, thereby reducing the amount of desired metal values partially or completely encapsulated by such material. The seeding agent may be generated in a number of ways, including the recycling of residue or the introduction of foreign substances. Processes embodying aspects of the present invention may be beneficial for recovering a variety of metals such as copper, gold, silver, nickel, cobalt, molybdenum, zinc, rhenium, uranium, rare earth metals, and platinum group metals from any metal-bearing material, such as ores and concentrates.
Type:
Grant
Filed:
September 9, 2002
Date of Patent:
September 30, 2003
Assignee:
Phelps Dodge Corporation
Inventors:
John O. Marsden, Robert E. Brewer, Joanna M. Robertson, David R. Baughman, Philip Thompson, Wayne W. Hazen, Roland Schmidt
Abstract: The electrolyte is supplied from a reservoir through at least one supply line to an electrolysis area including anodes and cathodes and at least one electric d.c. voltage source, and used electrolyte is at least partly recirculated from the electrolysis area back to the reservoir through at least one discharge line. Between a first contact point in the electrolyte of the supply line and a second contact point in the electrolyte of the discharge line there is a bridge line containing electrolyte, where the ohmic resistance R1 of the electrolyte in the bridge line between the first and the second contact point is not more than 10% of the ohmic resistance R2 which exists between the first and the second contact point in the electrolyte flowing through the reservoir. The amount of electrolyte flowing through the bridge line per unit time is not more than 5% of the amount of electrolyte flowing in the supply line in the vicinity of the first contact point.
Type:
Grant
Filed:
September 10, 2001
Date of Patent:
April 15, 2003
Assignee:
MG Technologies AG
Inventors:
Nikola Anastasijevic, Stefan Laibach, Friedhelm Münker, Markus Schweitzer, Walter Kühn
Abstract: The present invention relates to an electrowinning cell adapted to recover metal ions from a solution as their corresponding elementary metals. The electrowinning cell includes a reservoir and a filter in fluid communication with the reservoir. The filter is operative to receive a solution containing metal ions from a location proximate to the cathode and to retain a first portion of the solution having a first concentration of metal ions and to remove a second portion of the solution having a second concentration of metal ions lower than the first concentration. The electrowinning cell additionally includes return means operative to return the first portion of the solution to the reservoir. The present invention also relates to a method of concentrating metal ions in a solution for use in an electrochemical cell and to a system for reducing metal ions in a solution to their corresponding elementary metals.
Abstract: A method of producing a higher purity metal comprising the step of electrolyzing a coarse metal material by a primary electrolysis to obtain a primary electrodeposited metal, the step of electrolyzing the material with the primary electrodeposited metal obtained in the primary electrolysis step used as an anode to obtain a higher purity electrolyte for secondary electrolysis, and the step of further performing secondary electrolysis by employing higher purity electrolytic solution than said electrolytic solution with said primary electrodeposited metal as an anode, whereby providing an electro-refining method that effectively uses electrodes and an electrolyte produced in a plurality of electro-refining steps, reuses the flow of an electrolyte in the system, reduces organic matter-caused oxygen content, and can effectively produce a high purity metal.
Abstract: A galvanic cell system (50) in fluid communication with a dewatering system (40) of an inhibited oxidation scrubber (20) removes an oxidation catalyst, i.e., solution phase iron (98), from the process liquor (42) produced by the dewatering system (40) and replaces the iron (98) with magnesium (104) in an oxidation-reduction reaction. An electrolytic cell system (154) in fluid communication with a dewatering system (144) of a forced oxidation scrubber (128) removes an oxidation inhibitor, i.e., solution phase aluminum (174), from the process liquor (146) produced by the dewatering system (144) and replaces the aluminum (174) with iron (170) in an oxidation-reduction reaction. The process liquor (42, 146) is subsequently returned to the scrubber (20, 128) with the solution phase metal (98, 174) selectively removed, thereby enhancing the scrubbing efficiency of the scrubber (20, 128).
Type:
Application
Filed:
July 10, 2001
Publication date:
January 16, 2003
Inventors:
Bruce A. Salisbury, Kelly L. Baird, Calvin C. Webb
Abstract: An autonomous pushed liquid recirculation system (APLRS) is installed in a vessel, such as an electroplating tank. It situates around the interior perimeter and adjusts to changes in the level of liquid, maintaining the same location and orientation respective to the liquid's surface. It establishes a current near the surface that pushes liquid across the narrow horizontal dimension of the tank from a front wall to a rear wall. The current serves to push any bubbles resultant from operations within the tank to the rear wall. Over the rear wall is mounted an abbreviated exhaust hood covering only a short width of the surface of the tank along the rear wall. Because the exhaust system has to scavenge only a portion of the surface since all bubbles now burst along the rear wall, a much smaller air handling apparatus may be specified with an attendant savings in energy costs.
Abstract: A process for separating a first source of a heavy metal ion or mixtures of heavy metal ions, (Me1), from a solution comprising a complex of said Me1 and EDDS, (Me1-EDDS), by displacement of said Me1 with a second source of a heavy metal ion Me2 by addition to the solution of a salt of said Me2.
Type:
Grant
Filed:
February 28, 2001
Date of Patent:
November 26, 2002
Assignee:
The Procter & Gamble Company
Inventors:
Diederik Rudolf Schowanek, Tom Cornelis Jan Feijtel
Abstract: A drained-cathode cell for the electrowinning of aluminium comprises one or more anodes (14) suspended over one or more cathodes (16). The or each anode (14) and cathode (16) respectively have a sloped V-shaped active anode surface (22) and parallel sloped inverted V-shaped drained cathode surfaces (18) facing one another and spaced apart by two sloped inter-electrode gaps (20), arranged so the electrolyte circulates upwardly in the sloped inter-electrode gaps (20) assisted by anodically produced gas and then returns from a top part (22′) to a bottom part (22″) of each inter-electrode gap (20) along an electrolyte path (26,27,36,37).
Abstract: A method of preparing organic acids (fulvic, humic, and ulmic) for use as an electrolyte for producing high ionizations of precious metals (such as silver) which entails leaching out the organic acid from its source, stabilizing the organic acid first with ascorbic acid followed by sodium benzoate, removing cations, and using the organic acid as an electrolyte. A precious metal (such as silver) is used as a sacrificial electrode in this electrolyte. A non-sacrificial electrode could either be the same precious metal or an inert non-precious metal (titanium or graphite carbons). If the same material is used for the non-sacrificial electrode as for the sacrificial electrode, the size of each electrode may be about the same. If different material is used for the non-sacrificial electrode, its size should be larger that of the sacrificial electrode. Current at about 2 or more volts is applied to the electrodes and the ionization process begins yielding high concentrations of ionized precious metals.
Abstract: Lightweight and reactive metals can be produced from ore, refined from alloy, and recycled from metal matrix composites using electrolysis in electrolytes including an ionic liquid containing a metal chloride at or near room temperature. Low electric energy consumption and pollutant emission, easy operation and low production costs are achieved.
Type:
Application
Filed:
October 19, 2001
Publication date:
June 13, 2002
Applicant:
THE UNIVERSITY OF ALABAMA
Inventors:
Banqiu Wu, Ramana G. Reddy, Robin D. Rogers
Abstract: The present invention is directed to an improved process for the recovery of metal ions from metal-containing aqueous solutions using a supported liquid membrane (SLM) whereby the pH of the metal-containing solution is preferably adjusted to between 5.5 and 8 and ammonia or other weak base is present in the metal-containing solution in a concentration sufficient to form a complex between the weak base and metal ions present in the solution. The present invention permits enhanced recovery of metal in the solution without any need to adjust the pH of the solution during the SLM process.
Type:
Application
Filed:
May 23, 2001
Publication date:
May 23, 2002
Inventors:
Nikolai Kocherginsky, Andrew Grischenko
Abstract: Municipal solid waste is classified as to density as well as size in a perforated inclined trommel through which a gas stream is flowed inwardly through the perforations and downwardly to entrain and remove paper and plastics through the lower end. Ferrous and non-ferrous metals are removed from the residue which is digested anaerobically in two stages with an intermediate steam explosion treatment to expose cellulose fibers coated with lignin. Mercury may be removed as a vapor phase in an initial stage of the steam heating and condensed and collected. An aqueous phase of the anaerobic digestate may be treated to remove heavy metals and may be discarded or reused to slurry solid phase incoming to a digester. The solids phase of the anaerobic digestate may be acidified to solubilize heavy metals which are recovered by electrodeposition from the solution. The depleted residue can be neutralized and disposed of.
Type:
Grant
Filed:
February 22, 2000
Date of Patent:
April 30, 2002
Assignee:
Eastern Power Limited
Inventors:
Gregory M. Vogt, Hubert S. Vogt, Herman K. Walter
Abstract: A low temperature alkali metal electrolysis process for carrying out the electrolysis in the presence of a co-electrolyte and an alkali metal halide. The co-electrolyte comprises (1) a nitrogen-containing compound and optionally one ore more Group IB halides, Group IIIA halides, Group VIII halides; (2) a Group IIIA halide, a Group VB halide, or combinations of a Group IIIA halide and a Group VB halide; or (3) water. Further provided is an electrolyte comprising an alkali metal halide and a co-electrolyte that comprises (1) a nitrogen-containing compound and optionally one ore more Group IB halides, Group IIIA halides, Group VIII halides or (2) a Group IIIA halide, a Group VB halide, or combinations of a Group IIIA halide and a Group VB halide.
Type:
Grant
Filed:
March 28, 2000
Date of Patent:
April 9, 2002
Assignee:
E. I. du Pont de Nemours and Company
Inventors:
Jeffrey S. Thompson, Howard M. Blank, Walter John Simmons, Oswald Robert Bergmann
Abstract: A method and apparatus is utilized for producing colloidal dispersions of nanoparticles of electrically conducting materials. The colloidal dispersions are produced in a dense media plasma reactor comprising at least one static electrode and at least one rotating electrode. The plasma reaction sputters off minute particles of the electrically conducting material from which the electrodes are made. Methods of using the colloidal dispersions thus made are also described. Colloidal dispersions of silver produced in this manner are highly effective for bactericidal purposes.
Type:
Application
Filed:
June 13, 2001
Publication date:
March 28, 2002
Inventors:
Ferencz S. Denes, Sorin O. Manolache, Noah Hershkowitz
Abstract: A method and a device for recovering metals from a metal-containing flow, wherein: a) the metal-containing flow (7) and a solvent (8) are supplied to a dissolving unit (1), whereby a metal-containing solution is formed; b) the metal-containing solution is then supplied to a concentration unit (2); c) the metal-containing solution is separated in the concentration unit into a small-volume flow (14) containing a high concentration of metal salts and/or metal hydroxides, and a large-volume flow (13) containing a low concentration of metal salts and/or metal hydroxides; d) the small-volume flow (14) containing a high concentration of metal salts and/or metal hydroxides is supplied to an electrochemical unit (5); and e) the small-volume flow containing a high concentration of metal salts and/or metal hydroxides is separated in said electrochemical unit into a flow (16) containing one or more metals, and a flow (15) containing a low concentration of metal salts and/or metal hydroxides.
Type:
Grant
Filed:
March 22, 2000
Date of Patent:
March 12, 2002
Assignee:
Rafel Beheer B.V.
Inventor:
Michael Wilhelmus Hendrikus Maria DeWaart
Abstract: The present invention provides methods and compositions for use in recovery of metal from waste solutions minimally comprising tin as a dispersed insoluble oxide and iron as ferric ion. In general, the invention involves increasing the pH of the waste solution using a strong alkali to solubilize the tin, and adding a complexing agent(s) for other metal ionsin the solution, e.g., ferric ion, and/or cupric ion, and/or plumbous ion, so as to maintain the iron and other metal ions in a soluble state in the treated waste solution. The treated waste solution can then be used in an electroplating system to recover the tin and other metals. The electroplated, treated waste solution that is produced after tin recovery is environmentally safe, and, after pH adjustment, can generally be disposed of in most sanitary sewage systems.
Type:
Grant
Filed:
February 7, 2000
Date of Patent:
September 18, 2001
Assignee:
RD Chemical Company
Inventors:
Douglas W. McKesson, Jr., Rudolf P. Sedlak
Abstract: A process for producing metallic lithium starting from an aqueous solution of at least one lithium salt comprises the following steps:
(I) Production of a lithium amalgam from an aqueous solution of at least one lithium salt; and
(II) Electrolysis using an anode comprising the lithium amalgam, a solid electrolyte which conducts lithium ions, and liquid lithium as cathode, wherein the lithium amalgam as anode is kept in motion.
Type:
Grant
Filed:
March 20, 2000
Date of Patent:
September 11, 2001
Assignee:
BASF Aktiengesellschaft
Inventors:
Kerstin Schierle-Arndt, Hermann Pütter, Günther Huber, Dieter Schläfer, Josef Guth
Abstract: The present invention concerns a composition and method for separating heavy metals from contaminated substrates with compositions containing active agent selected from the group consisting of [S,S]-ethylene diamine disuccinic acid and [S,S]-di-imine butane dioic acid.
Type:
Grant
Filed:
July 21, 1999
Date of Patent:
July 24, 2001
Assignee:
The Procter & Gamble Co.
Inventors:
Diederik Rudolf Schowanek, Tom Cornelis Jan Feijtel
Abstract: The present invention relates to a process for obtaining metals from oxides using shuttle alloys, particularly titanium metal from titanium dioxide in the form of illmenite rutile. The process can be adapted to obtain elemental metal or alloys of metals such as zirconium, chronium, molybdenum, tungsten, tantalum, lithium, cobalt and zinc. The process of the present invention comprises two stages, a first stage in which a metal oxide is reduced in the presence of primary shuttle material, which forms a shuttle alloy with the reduced metals, and a second stage wherein the reduced metal is separated from the shuttle alloy as a metal or alloy. Typically the primary shuttle material comprises bismuth or antimony or a mixture of the two and optionally lead. The reduction reaction may be carried out by chemical means or electrochemical means or by a combination of the two.
Abstract: A procedure for the generation of organosulfonic acids from solutions of corresponding metal organosulfonate compounds by electrowinning, electrolytically driven hydrolysis or chemically driven hydrolysis is described. Appropriate organosulfonate compounds include the water soluble salts of alkanesulfonic and aromatic sulfonic acids which incorporate metals from Group VIB, VIIB, VIIIB, IB, IIB or VA of the periodic table. The electrowinning and electrolytic techniques described can be applied in divided or undivided cells and can be operated in continuous fashion to provide the greatest efficiency. Hydrolysis based methods can employ either anodic oxidation or oxidation both of which function to oxidize the metal cation(s) present to hydrolytically unstable higher oxidation states.
Type:
Grant
Filed:
April 8, 1999
Date of Patent:
February 13, 2001
Assignee:
ATOFINA Chemicals, Inc.
Inventors:
Michael D. Gernon, Nicholas M. Martyak, Martin Nosowitz, Gary S. Smith
Abstract: The present invention relates to a process for separating technetium from a nitric solution of technetium through cathodic electrodeposition of said technetium by electrolysis. According to the process of the invention, the nitric solution of technetium is denitrified and its pH is adjusted to a value of approximately 5.5 to 7.5 before electrolysis. Electrolysis is conducted at galvanostatic rate, and the cathode potential is approximately −1.36 V/SHE to −1.16/SHE. The ratio of the cathode surface area (S) to the volume of the technetium solution to be electrolyzed may be in the region of 0.25 to 0.50 cm−1.
Type:
Grant
Filed:
June 7, 1999
Date of Patent:
January 30, 2001
Assignees:
Commissariat a l'Energie Atomique, Compagnie Generale des Matieres Nucleaires
Inventors:
Michel Masson, Micha{umlaut over (e)}l Lecomte, Alexandre Masslennikov, Vladimir Peretroukhine
Abstract: Copper is extracted from a heap of low-grade ore by transforming the heap into an electrolytic cell, and imposing a voltage thereon. Anodic conditions of redox and pH cause the sulphide to break down, and the copper to pass into solution. The copper can be recovered elsewhere if the electrolyte is drawn off, or in-situ if allowed to plate onto the cathode. Electrodes are formed as grids of conductors, or as layers of e.g. graphite.
Abstract: The present invention is directed to a process for removing various contaminants (e.g., organic collectors, contaminant metals or spectator ions, and/or suspended and colloidal solids) from process streams in leaching processes. The contaminant removal is performed by one or more membrane filtration systems (e.g., nanofilters, ultrafilters, and/or microfilters) treating process streams including, the pregnant leaching solution, the barren raffinate, and the lean and rich electrolytes.
Abstract: A high performance method for recovery of metal from aqueous solutions is carried out using an electrochemical cell having a cathode assembly that includes a nonporous support member, a primary cathode, and a nonconductive or conductive porous material covering the primary cathode. An anode is spaced apart from the cathode assembly. Fluid is caused to flow through the porous material to the primary cathode, through openings or fluid collection channels in the nonporous support member, and uniformly out of the cell. Uniform and efficient deposition of metal is accomplished over the entire cathode assembly because of modulation of fluid flow and increased mass transfer.
Type:
Grant
Filed:
October 27, 1998
Date of Patent:
November 21, 2000
Assignee:
Eastman Kodak Company
Inventors:
James J. Carey, Gary P. Wainwright, Stephen N. Lowery, Robert B. Call, Peter J. Kelch
Abstract: A method for extracting and reclaiming metals from scrap CdTe photovoltaic cells and manufacturing waste by leaching the waste with a leaching solution comprising nitric acid and water, skimming any plastic material from the top of the leaching solution, separating the glass substrate from the liquid leachate and electrolyzing the leachate to separate Cd from Te, wherein the Te is deposits onto a cathode while the Cd remains in solution.
Type:
Grant
Filed:
June 16, 1998
Date of Patent:
December 7, 1999
Assignee:
Drinkard Metalox, Inc.
Inventors:
Robert E. Goozner, Mark O. Long, William F. Drinkard, Jr.
Abstract: Disclosed is a method for reducing metal acid or salt evolved from electrolytic baths housed in electrolytic tanks during electrolytic operations. This method involves covering all of the surface of the electrolytic bath with a layer of shredded foam (e.g., polymeric foam, metal foam, glass foam, or vitreous material foam). The shredded foam is irregular in shape, lacking in uniform particle size, is inert to the electrolytic operation, and floats at the surface of the electrolytic bath. Desirably, the layer of shredded foam is about 3 to 4 inches (76-102 mm) in thickness. Examples of specific processes benefiting from the present invention are anodizing, electroplating, electrowinning, and electrophoresis operations.
Abstract: A method and apparatus for electrolytically extracting lithium at high purity and high efficiency are disclosed, in which the apparatus 1 includes a partition 2 constituted mainly of a perovskite-type Li ion conducting solid electrolyte, a feed chamber formed on one side of the partition in which a crude liquid containing a lithium component and impurities is introduced so as to come into contact with the partition, a recovery chamber formed on the other side of the partition in which a liquid for recovery is introduced so as to come into contact with the partition, and a means for applying an electrical field to the partition in such a manner that the crude liquid side is positive and the recovery liquid side is negative. On applying an electrical field to the partition, the lithium component of the crude liquid selectively passes through the partition in the form of Li ions into the recovery side.
Abstract: A method is provided for the hydrometallurgical recovery of metal values from metal sources containing more than one metal such as antimony, lead, copper, zinc, bismuth, tin, cadmium and other metals by leaching the metal containing source with a ferric fluoborate/fluoboric acid solution to provide a metal containing leach solution. The leach solution is extracted with organic extractants, ion exchange resins and the like to provide a loaded extract and a raffinate which contains fluoboric acid produced in the extraction step. The fluoboric acid concentration is controlled (reduced) in the raffinate by adding to the raffinate a metal oxide of a metal in the raffinate to form an acid adjusted raffinate. The acid adjusted raffinate is then electrowon or otherwise treated to form the desired metal and to provide a ferric fluoborate solution which is recycled for leaching additional metal containing material.
Type:
Grant
Filed:
March 26, 1998
Date of Patent:
August 10, 1999
Assignee:
ASARCO Incorporated
Inventors:
Michael G. King, Shijie J. Wang, Venkoba Ramachandran
Abstract: A radioactive waste stream (12) is of high pH and contains a wide variety of different fission products and also organic materials which act as complexants. Technetium and/or ruthenium are removed by first electrolytically oxidising the organic materials at an anodically stable anode (26), and then electrolytically reducing the technetium and/or ruthenium at a porous fluid-permeable cathode (42). The cathode (42) might for example be of lead wool.
Type:
Grant
Filed:
October 21, 1997
Date of Patent:
April 13, 1999
Assignee:
AEA Technology plc
Inventors:
Christopher Peter Jones, Paul Antony Harry Fennell, Patrick Alan Fletcher
Abstract: Ores containing copper, zinc, silver in the form of sulfides are treated by a solution of sulfurated sulfite ions and ammonium ions in order to remove most of the metals from the sulfide ores. This treatment renders the resulting gold bearing ores much more amenable to cyanide extraction. Dissolved metals are reclaimed by appropriate techniques, such as electrowinning or liquid-liquid extraction, and the solution of sulfurated sulfites and ammonia is recycled for further lixiviation of fresh ores.
Type:
Grant
Filed:
January 17, 1997
Date of Patent:
March 2, 1999
Assignee:
UG Plus International Inc.
Inventors:
Jean-Marc Lalancette, Hugues Menard, Regina Zamojska
Abstract: An inexpensive electrowinning electrode has a cathode that is a porous form made from conductive filaments, and an anode. The electrowinning process dissolves a contaminated metal stream into an electrolyte to form a solution flow of dissolve metal and contaminants. Next, the solution is oxidized. Then, the dissolved metals in the solution are plated onto the porous cathode.
Type:
Grant
Filed:
April 21, 1997
Date of Patent:
November 17, 1998
Assignee:
The Scientific Ecology Group, Inc.
Inventors:
Thomas Stephen Snyder, John Gregorie Wagner
Abstract: A method for extracting and reclaiming metals from scrap CIS photovoltaic cells and associated photovoltaic manufacturing waste by leaching the waste with dilute nitric acid, skimming any plastic material from the top of the leaching solution, separating glass substrate from the leachate, electrolyzing the leachate to plate a copper and selenium metal mixture onto a first cathode, replacing the cathode with a second cathode, re-electrolyzing the leachate to plate cadmium onto the second cathode, separating the copper from selenium, and evaporating the depleted leachate to yield a zinc and indium containing solid.
Type:
Grant
Filed:
May 12, 1997
Date of Patent:
July 14, 1998
Assignee:
Drinkard Metalox, Inc.
Inventors:
William F. Drinkard, Jr., Mark O. Long, Robert E. Goozner
Abstract: An electrochemical cell is provided for removal of metals such as copper, lead, silver, tellurium, platinum, palladium or nickel from dilute solutions of the metal. The cell comprises a porous tubular support (18) which is provided with a cathode comprising a porous carbon fiber material (19), a current feeder (15) for the cathode, a tubular anode (12) spaced from said cathode, a current feeder (16) for the anode, the anode and the cathode being enclosed by a non-porous outer casing (11). In use the dilute solution from which the metal is to be removed is introduced into the cell through an inlet (13) and flows through the porous carbon fiber cathode to an outlet (14). The cell is useful for removing harmful metals from wastes so that they are environmentally acceptable for disposal and for recovery of valuable metals.
Type:
Grant
Filed:
March 7, 1996
Date of Patent:
November 25, 1997
Assignee:
EA Technology Ltd.
Inventors:
John Garry Sunderland, Ian McCrady Dalrymple
Abstract: The anode comprises a substantially horizontal carrying bar, which is disposed outside the electrolyte and serves to supply electric current. Two substantially parallel metal surfaces (anode grids) are electrically conductively connected to the carrying bar and with at least one-half of their surface extending into the electrolyte. The carrying bar comprises a copper conductor, to which at least one vertical copper rod is joined. There is a direct electrically conducting connection between the copper conductor and the copper rod. The copper rod is surrounded by a titanium sheath and is an interference fit in that sheath. The copper rod provided with the titanium sheath is disposed between the two anode grids and is electrically conductively connected to said grids.
Type:
Grant
Filed:
July 11, 1996
Date of Patent:
October 21, 1997
Assignee:
Metallgesellschaft Aktiengesellschaft
Inventors:
Nikola Anastasijevic, Gerhard Jedlicka, Karl Lohrberg
Abstract: Process for the production of pure tungsten and/or molybdenum solutions from sources, such as alkaline decomposition solutions, which are contaminated with tantalum, niobium, titanium, aluminium, tin, arsenic, phosphorus and/or silicon, by application of a three stage purification process of pH reduction, anion exchange and membrane electrolysis.
Abstract: Zinc metal is deposited on mobile seed particles in an electrowinning process. Exceptionally favorable results in terms of production rate, current efficiency and energy consumption are achieved by using a unique combination of design parameters and operating conditions achieved by selected ranges for particle size, current density, particle bed thickness, and acid content of the electrolyte.
Type:
Grant
Filed:
August 30, 1995
Date of Patent:
June 3, 1997
Assignee:
The Regents of the University of California
Inventors:
Juan C. Salas-Morales, Stanley C. Siu, James W. Evans, Oliver M. G. Newman
Abstract: The method of removing sulfurous compounds (organic and inorganic) from any fluid (gas or liquid) phase by contacting said fluid (gas or liquid) with the reactive metal to form a metal sulfide recovering said fluid (gas or liquid) free from said sulfurous compound and containing compounds free from sulfur and recovering electrochemically said reactive metal from said sulfur to return said metal to elemental form to release elemental sulfur, said separating being done at temperatures above melting point of sulfur.
Abstract: An electrochemical system for the recovery of metals from metal ores in which reactions are carried out in separate anode and cathode tanks with the liquid product from the anode tank being separated and purified before being returned to the cathode tank for metal deposition. The separation includes thickening such as liquid solid separation with the liquid proceeding to the cathode tank. A reaction stage may be included before the thickening stage. Purification may include removal of impurities, adjustment of chemical and physical conditions and the addition of cathode reaction enhancers.
Abstract: A non-aqueous electrolyte secondary battery having a long cycle life and a high reliability with substantially no internal short-circuit is provided by incorporating crystalline metal lithium as its negative electrode. The crystalline metal lithium is electrochemically deposited on a metal substrate in an electrolyte including a tetrahydrofran derivative or a 1,3-dioxolan derivative as a solvent.
Type:
Grant
Filed:
October 7, 1994
Date of Patent:
September 24, 1996
Assignee:
Matsushita Electric Industrial Co., LTD.
Abstract: The conditions for electrowinning Zn, Ni, Co and Cd metals from baths based on chlorinated ammino complexes of Me(NH.sub.3).sub.n Cl.sub.m type are substantially improved by the addition of small levels of dissolved Br, which considerably reduce the cell voltage without exerting any negative effects on cathodic current yields.
Abstract: The invention relates to a process for obtaining a fine powder of dendritic cadmium, characterized in that it comprises the following steps:(a) electrolytic production of cadmium metal on an electrode, under conditions such that there is formed a sponge consisting of tangled polymorphic dendrites,(b) removal and washing of the sponge,(c) disintegration of the sponge in a pulpy medium under conditions such that the dendrites are released in order to obtain a dendritic powder of particle size essentially less than a specified limit.
Abstract: A process for producing one or more metals from a mineral feedstock (12) is defined. The mineral is fed to a leaching apparatus (10) wherein it is contacted with electrolyte (14). The leaching apparatus has zones of decreasing oxidation potential (17, 18, 19, 20) respectively. A stream of electrolyte (14A) is removed from zone (20) and is treated to remove impurities and unwanted metals in treatment unit (25A), prior to metal recovery by electrolysis. The electrolyte after electrolysis is then returned to the leaching unit (10). A second electrolyte stream (14B) may be removed from zone (19) for recovery of additional metals. The electrolyte (14B) is treated to remove impurities and any unwanted metals in treatment unit (25B), prior to metal recovery by electrolysis. The electrolyte after electrolysis is returned to leaching unit (10). The process enables the leaching of difficult to leach minerals, including gold, and can produce one or more metals of high purity.