Group Vib Metal (cr, Mo, Or W) Patents (Class 423/53)
  • Patent number: 4162295
    Abstract: A method for producing alkali metal chromates by double roasting chrome ores without the use of alkaline earths is disclosed. The pollution and hygiene problems associated with the use of lime are substantially eliminated and only negligible amounts of alumina are found in the product chromate liquors without employing steps previously thought necessary. These advantages are achieved by controlling (1) the Bichromate Equivalent: aluminum oxide ratio in the mix, (2) the amount of alkali metal salts added to the mix, (3) the roasting time, (4) the composition and alkalinity of the liquor used for leaching the roast, and (5) the temperature employed, in both roasts.
    Type: Grant
    Filed: November 14, 1977
    Date of Patent: July 24, 1979
    Assignee: Allied Chemical Corporation
    Inventors: Somanahalli N. Subbanna, Thomas R. Morgan, Douglas G. Frick
  • Patent number: 4159309
    Abstract: Reducible pollutants can be detoxified by reduction and metals can be recred by reduction of the corresponding metal ions by bringing into contact a catalyst with the solution which is suitable for the electrochemical reduction of the ions in question, and mixing into the solution (or bubbling therethrough in the case of a gas) a reducing agent that has a redox potential in the redox system of the reducing agent and its oxidation product that is more negative than the redox potential of the substance to be reduced and its reduction product. The catalyst is a material that is suitable for use as an anode material at which hydrogen can be oxidized in a fuel cell. Such catalysts include finely divided platinum, activated carbon coated with platinum, tungsten carbide and activated carbon coated with tungsten carbide, particularly. Hydrogen is a good reducing agent for the purpose.
    Type: Grant
    Filed: March 24, 1978
    Date of Patent: June 26, 1979
    Assignee: Kernforschungsanlage Julich Gesellschaft mit beschrankter Haftung
    Inventors: Wolfgang Faul, Bertel Kastening
  • Patent number: 4151257
    Abstract: A method for recovering nonferrous metal values from hydroxide sludge wastes containing same by first chlorinating the aqueous waste to oxidize the chromium therein, separating the insoluble components therefrom and treating the resulting Cr(VI) solution in a fixed bed anion exchanger to separate the Cr(VI) from the solution, separating the copper from the aqueous solution by liquid-liquid extraction, separating the zinc from the copper-free solution by liquid-liquid extraction, precipitating and separating the aluminum in the form of hydroxide from the zinc-free solution and then separating the nickel from the aluminum-free solution by liquid-liquid extraction, and recovering the nonferrous metals from the respective solutions and precipitates by conventional procedures.
    Type: Grant
    Filed: January 16, 1978
    Date of Patent: April 24, 1979
    Assignee: Th. Goldschmidt AG
    Inventors: Wolfgang Muller, Lothar Witzke
  • Patent number: 4144310
    Abstract: An energy efficient process is disclosed for the hydrometallurgical oxidation of sulfidic minerals containing copper, silver, nickel, cobalt, molybdenum, or zinc values. A high density slurry, e.g., 67% by weight solids, is prepared from a particulate sulfide mineral and water. Nitrogen dioxide and preferably also oxygen are added to the slurry to oxidize the sulfidic minerals and to produce solubilized cations and nitric oxide. The nitric oxide is oxidized to nitrogen dioxide, thereby regenerating the principal oxidant. If oxygen is added to the slurry along with NO.sub.2, then the regeneration occurs in-situ.
    Type: Grant
    Filed: November 30, 1977
    Date of Patent: March 13, 1979
    Assignee: Kennecott Copper Corporation
    Inventors: Theodore C. Frankiewicz, Robert E. Lueders
  • Patent number: 4138248
    Abstract: A process for the recovery of copper, molybdenum, gold and elemental sulfur in tailings from hydrometallurgical processing of copper sulfide ores, the process comprising concentrating the tailings containing elemental sulfur and copper, gold and molybdenum to a small bulk volume by froth flotation to reject barren gangue including jarosite, if present, and other impurities, separating the liquids and solids in the float concentrate, leaching the resulting residue with a solvent for sulfur followed by liquid-solids separation and recovering elemental sulfur from the liquid, leaching the residue from the sulfur solvent leach with ferric chloride to selectively dissolve copper and iron therein followed by liquid-solids separation and recovering copper from the liquid or sending it back to the hydrometallurgical circuit, leaching the residue from the ferric chloride leach with cyanide to selectively solubilize gold followed by liquid-solids separation and recovering of solubilized gold from the liquid, recovering
    Type: Grant
    Filed: April 10, 1978
    Date of Patent: February 6, 1979
    Assignee: Cyprus Metallurgical Processes Corporation
    Inventor: Kartik A. Narain
  • Patent number: 4138466
    Abstract: In the recovery of chromium from a residue containing chromate and vanadate, by oxidative decomposition of a chromium and vanadium-containing ore in the presence of an alkali at temperatures of about 600 to 1200.degree. C., and leaching such residue with water, the improvement which comprises adding titanium dioxide to the residue and heating, whereby upon leaching the chromium enters the water while the vanadium is substantially left in the residue.
    Type: Grant
    Filed: October 11, 1977
    Date of Patent: February 6, 1979
    Assignee: Bayer Aktiengesellschaft
    Inventors: Johann N. Meussdoerffer, Wolfgang Bockelmann, Hans Niederprum
  • Patent number: 4132758
    Abstract: Sulfidic minerals containing metal values such as copper, silver, nickel, cobalt, molybdenum, zinc, iron, or mixtures thereof are oxidized with nitrogen dioxide to enable the metal values to be solubilized in an aqueous acidic leach liquor. In practicing the invention, the minerals are added to an aqueous acidic leach liquor and a nitrogen dioxide containing gas is sparged through the slurry to oxidize the metal values. During the reaction, the nitrogen dioxide is reduced to nitric oxide. The nitric oxide is oxidized to nitrogen dioxide by oxygen, either in-situ, or in a separate off-gas oxidizer.
    Type: Grant
    Filed: November 30, 1977
    Date of Patent: January 2, 1979
    Assignee: Kennecott Copper Corporation
    Inventors: Theodore C. Frankiewicz, Robert E. Lueders
  • Patent number: 4119696
    Abstract: Titanium metal values may be recovered from a metal bearing source by subjecting the source to an oxidation step. The oxidized source is then divided, one portion being set to a reductive roast followed by leaching with hydrochloric acid. Thereafter, the remaining portion of the oxidized source is brought into contact with the leached solution whereby titanium dioxide is precipitated. The precipitated titanium dioxide is separated and recovered while the soluble metal values are treated for recovery thereof with a concurrent formation of hydrogen chloride, the latter being recycled back to the leaching zone.
    Type: Grant
    Filed: November 14, 1977
    Date of Patent: October 10, 1978
    Assignee: UOP Inc.
    Inventor: William K. Tolley
  • Patent number: 4115110
    Abstract: A process for recovering vanadium values from carbonaceous type vanadium ores, and vanadium scrap, such as vanadium contaminated spent catalyst, is disclosed which comprises roasting the vanadium containing material in air at a temperature less than about 600.degree. C to produce a material substantially devoid of organic matter, subjecting said roasted material to a further oxidizing roast in an oxygen atmosphere at a temperature of at least about 800.degree. C for a period sufficient to convert substantially all of the vanadium to the soluble form, leaching the calcine with a suitable dilute mineral acid or water at a pH of neutral to about 2 to recover vanadium values, precipitating vanadium values as iron vanadate from the leach solution with a soluble iron compound at a pH from neutral to about 1, and recovering ferrovanadium from the iron vanadate by a reduction vacuum smelting operation.
    Type: Grant
    Filed: April 8, 1977
    Date of Patent: September 19, 1978
    Assignee: Earth Sciences, Inc.
    Inventors: Roman Z. Pyrih, Robert S. Rickard
  • Patent number: 4113471
    Abstract: A process for extracting non-ferrous metal values from an oxide ore. The process comprises leaching the ore with a solution containing at least one alkali metal chloride or alkaline earth chloride salt in the presence of an oxygen-containing gas at a temperature and pressure sufficient to solubilize the non-ferrous metal values into the solution of the metal chloride salt.
    Type: Grant
    Filed: December 2, 1976
    Date of Patent: September 12, 1978
    Assignee: The Dow Chemical Company
    Inventors: Martin A. Langhorst, Gerard C. Sinke, Elmer H. Mossner
  • Patent number: 4112046
    Abstract: In the disintegration of at least one chromium source selected from the group consisting of a SiO.sub.2 -containing chromite and a chromium-containing residue with an alkali compound at a temperature above about 800.degree. C in the presence of atmospheric oxygen and a lime-free diluent, followed by leaching of the mixture with at least one of water and/or a chromium (VI)-containing aqueous solution, the improvement which comprises including in the mixture to be disintegrated an aluminum compound and at least sufficient alkali to form alkali chromate and to convert the SiO.sub.2 into an alkali-aluminum silicate corresponding to the formula nMe.sub.2 O . mSiO.sub.2 . Al.sub.2 O.sub.3, wherein Me is at least one of sodium and potassium, 0.8 .ltoreq. n .ltoreq. 1.2 and 1.3 .ltoreq. m .ltoreq. 4.3.
    Type: Grant
    Filed: December 3, 1976
    Date of Patent: September 5, 1978
    Assignee: Bayer Aktiengesellschaft
    Inventors: Hans Niederprum, Johann-Nikolaus Meussdoerffer, Hans-George Nieder-Vahrenholz, Wolfgang Bockelmann
  • Patent number: 4107262
    Abstract: A process in which copper, nickel, cobalt and molybdenum are recovered by reducing comminuted raw manganese nodules with an aqueous solution containing cuprous ions. An improvement is disclosed in which copper is oxidized to provide a starting solution of cuprous ions for the process. In one important embodiment of the invention wet copper cement is added to a solution of carbon dioxide and ammonia and ground manganese nodules are then added to the mixture. As a result, a starting solution containing cuprous ions is produced. A major advantage gained from utilizing manganese nodules as an oxidizing agent is that the manganese nodule is itself reduced and its metal values are added to the reaction solution.
    Type: Grant
    Filed: August 26, 1974
    Date of Patent: August 15, 1978
    Assignee: Kennecott Copper Corporation
    Inventors: Robert E. Lueders, Roger N. Kust, David S. Davies
  • Patent number: 4087510
    Abstract: Vanadium and molybdenum are recovered from a spent desulfurization catalyst containing the same by a process involving intimately admixing with comminuted catalyst an amount of a solid alkali metal carbonate, such as calcined sodium carbonate, sufficient to convert the vanadium and molybdenum present into water-soluble compounds, heating the mixture in the solid state in the presence of air at a temperature between about 650.degree. C and about 850.degree. C for a period of about 1 to 2 hours, and extracting the vanadium and molybdenum compounds with water.
    Type: Grant
    Filed: December 18, 1975
    Date of Patent: May 2, 1978
    Assignee: Akzona Incorporated
    Inventor: Gerhard E. W. K. Steenken
  • Patent number: 4086319
    Abstract: A process is disclosed for incinerating tannery waste solids containing organic material and chromium which comprises burning at least one ton per day of said waste in the combustion zone of an industrial furnace at a low temperature, preferably between about 800.degree. F. and 1200.degree. F., to convert at least a portion of the organic material to gases and the chromium to ash, removing the gases from the combustion zone and subjecting them to further oxidation, and removing the ash from the furnace. The waste solids include sludge separated from liquid waste, leather scrap, or preferably both. By controlling temperature, waste composition, or both, the chromium in the ash can be obtained in either trivalent or hexavalent form. The hexavalent chromium can be extracted with solvent for reuse in the tanning process. Trivalent chromium, with or without carbon, can be recovered as chromic oxide in an improved stable form for landfill, storage or shipment to a reprocessing center.
    Type: Grant
    Filed: November 8, 1976
    Date of Patent: April 25, 1978
    Inventor: Bradford H. Jones
  • Patent number: 4085188
    Abstract: A process for extracting metal values from sea nodules is provided in which nickel, cobalt and copper values are selectively extracted by leaching raw sea nodules in an aqueous ammoniacal medium in the presence of a reducing agent for tetravalent manganese and carbonate to precipitate the reduced manganese as manganous carbonate.
    Type: Grant
    Filed: March 8, 1976
    Date of Patent: April 18, 1978
    Assignee: The International Nickel Company, Inc.
    Inventors: Kohur Nagaraja Subramanian, Gerald Vernon Glaum
  • Patent number: 4083922
    Abstract: A process is provided for the manufacture of a tungstate salt, especially ammonium tungstate. The process comprises treating finely divided metallic tungsten and/or intermetallic iron/tungsten species with an aqueous solution in the presence of an oxidizing agent, such as oxygen or hydrogen peroxide. The solution contains cations which are ammonium and/or alkali-metal ions and anions which are hydroxide, carbonate and/or bicarbonate ions. The finely divided material generally contains no more than impurity quantities of alkaline earth metals. The process is useful in deriving tungsten values from wolframite ores, which are reduced prior to the aqueous treatment.
    Type: Grant
    Filed: January 27, 1977
    Date of Patent: April 11, 1978
    Assignee: Du Pont of Canada Limited
    Inventor: Hans Peter Kasserra
  • Patent number: 4083921
    Abstract: Copper, iron, and lead impurities are removed from molybdenum flotation concentrates by mixing the feed concentrates with a nonvolatile chloride salt, heating the mixture to a temperature of from about 200.degree. to 350.degree. C for a time sufficient to activate the lead impurities in the concentrates so that they can be leached therefrom during the subsequent leach step, and leaching copper, iron, and lead impurities from the heat-treated concentrates with a mildly oxidizing leach solution containing chloride ions and having a pH of no more than 4. Preferably, the mixing of the chloride salt and the feed concentrates is achieved by thoroughly mixing an aqueous solution of the salt with the feed concentrates.
    Type: Grant
    Filed: January 3, 1977
    Date of Patent: April 11, 1978
    Assignee: Kennecott Copper Corporation
    Inventor: Rolf Jurgen Wesely
  • Patent number: 4083920
    Abstract: A process is provided for extracting tungsten values from tungsten compositions. The process comprises treating a tri (alkaline earth metal) tungstate, especially tricalcium tungstate, at a temperature of preferably no greater than 50.degree. C. with a aqueous solution of hydrochloric and/or nitric acid, preferably having a concentration of no greater than 5 molar. The acid is supplied in excess of te stoichiometric amount required to convert the tungstate to tungstic acid and sufficient to maintain the thusly formed tungstic acid insoluble in the solution. The tungstic acid can then be separated from the solution and converted to soluble ammonium tungstate, which in turn can be converted into tungsten trioxide and finally into metallic tungsten. The tri (alkaline earth metal) tungstate starting material can be prepared from iron tungstate, manganese tungstate, and/or an alkaline earth metal tungstate or from ores or concentrates of these tungstates, by a high temperature treatment with calcium oxide.
    Type: Grant
    Filed: January 27, 1977
    Date of Patent: April 11, 1978
    Assignee: Du Pont of Canada Limited
    Inventors: Stephen Peter Beaton, Hans Peter Kasserra
  • Patent number: 4080421
    Abstract: A process is provided for preparing ammonium tungstate. In the process, a reduced calcium tungstate is treated in the presence of an oxidizing agent with an aqueous solution having at least ammonium cations and carbonate and/or bicarbonate anions, at a temperature of 10.degree. C to the boiling point of the solution. The reduced calcium tungstate reacts with the ammonium cations to form the ammonium tungstate which is soluble in the solution and with the anions to form a calcium compound which is insoluble in the solution. Oxygen and/or hydrogen peroxide are preferred oxidizing agents. The process is especially useful in separating tungsten values from scheelite ores or concentrates.
    Type: Grant
    Filed: January 27, 1977
    Date of Patent: March 21, 1978
    Assignee: Du Pont of Canada Ltd.
    Inventor: Hans Peter Kasserra
  • Patent number: 4080420
    Abstract: A process is provided for treating tri (alkaline earth metals) tungstates with an aqueous solution containing cations selected from ammonium, sodium and potassium ions and mixtures thereof, and anions selected from hydroxide, carbonate, bicarbonate, and phosphate ions and mixtures thereof, to form a tungstate salt which is soluble in the solution and an alkaline earth metal compound which is insoluble in the solution. The tri (alkaline earth metal) tungstate can be prepared from iron tungstate, manganese tungstate, and/or an alkaline earth metal tungstate or from ores or concentrates of these tungstates, by a high temperature treatment with an alkaline earth metal donor compound, such as calcium oxide. A preferred soluble tungstate is ammonium tungstate, which can be further processed to yield tungsten trioxide and/or tungsten.
    Type: Grant
    Filed: January 27, 1977
    Date of Patent: March 21, 1978
    Assignee: Du Pont of Canada Ltd.
    Inventors: Hans Peter Kasserra, Denis Bertram Kelly, Isaac Obadia
  • Patent number: 4075277
    Abstract: A process of recovering molybdenum in the form of molybdic acid from waste products and particularly from spent catalysts containing a support based on gamma-alumina wherein the molybdenum is in the form of molybdenum oxide or molybdenum sulfide comprising treating the waste products with sodium carbonate and heating to convert the molybdenum present to sodium molybdate, and converting the sodium molybdate to molybdic acid by treatment with concentrated nitric acid to produce molybdic acid high in purity that is suitable for the production of molybdenum compounds as well as for the recovery of the pure metal.
    Type: Grant
    Filed: January 31, 1977
    Date of Patent: February 21, 1978
    Assignee: Metaux Speciaux S.A.
    Inventors: Herman Castagna, Guy Gravey, Andre Roth
  • Patent number: 4075278
    Abstract: A process of recovering molybdenum from waste products and particularly from spent catalyst based on active alumina and containing molybdenum compounds comprising mixing the spent catalyst with sodium carbonate powder, adding water and remixing to absorb the water in the catalyst particles, baking the mixture to convert the molybdenum present to sodium molybdate, treating the mixture at ambient temperature with carbon dioxide gas, treating the resultant mixture with hot water to dissolve the sodium molybdate, neutralizing and clarifying with concentrated nitric acid, and precipitating to produce molybdic acid high in purity that is suitable for the production of molybdenum compounds as well as for the recovery of the pure metal.
    Type: Grant
    Filed: February 3, 1977
    Date of Patent: February 21, 1978
    Assignee: Metaux Speciaux S.A.
    Inventors: Guy Gravey, Paul Grolla, Andre Roth
  • Patent number: 4066733
    Abstract: A process is disclosed for extracting nickel, copper, cobalt and molybdenum from a complex ore containing copper, nickel, cobalt, molybdenum, manganese and iron. The process features treatment of the ore with gaseous compound followed by leaching with an aqueous ammonia/ammonium salt solution into which is additionally introduced sulfite.
    Type: Grant
    Filed: September 30, 1976
    Date of Patent: January 3, 1978
    Assignee: Ethyl Corporation
    Inventors: Michael Dubeck, Gordon G. Knapp
  • Patent number: 4065544
    Abstract: Finely-divided metal oxides are prepared by the steps of (a) contacting a compound of a metal with a carbohydrate material to obtain an intimate mixture thereof, (b) igniting this mixture to oxidize the same and to insure conversion of substantially all of said metal compound to a fragile agglomerate of its metal oxide, and (c) pulverizing the product of step (b) to form a finely-divided metal oxide powder having a mean particle size below about 1.0 micron. Certain of the finely-divided metal oxide powders produced by this process have the useful property of sinterability at temperatures significantly lower than metal oxide powders heretofore readily available. The powders are useful in the preparation of high strength compacted shapes for use in high temperature and/or corrosive environment, in the preparation of refractory cements, catalysts, catalysts supports and the like.
    Type: Grant
    Filed: June 20, 1974
    Date of Patent: December 27, 1977
    Assignee: Union Carbide Corporation
    Inventors: Bernard H. Hamling, Alfred W. Naumann
  • Patent number: 4049438
    Abstract: Manganiferous deep sea nodules containing non-ferrous metal values are selectively reduced to reduce manganic oxides to manganous oxide (MnO) and the non-ferrous metal values to the metallic state, and the selectively reduced nodules are then smelted to produce a molten metallic alloy containing the non-ferrous metal values and a slag containing most of the manganese. The molten alloy is blown with a free-oxygen-containing gas to eliminate most of the manganese, and the substantially manganese-free metal is then sulfided to produce a matte suitable for separation and recovery of the non-ferrous metal values. After sulfiding the matte can be blown with a free-oxygen-containing gas to lower the iron content thereof. Not all the iron is removed if it is advantageous to keep a high proportion of cobalt in the matte.
    Type: Grant
    Filed: February 14, 1975
    Date of Patent: September 20, 1977
    Assignee: The International Nickel Company, Inc.
    Inventors: Ramamrithan Sridhar, John Stuart Warner, Malcolm Charles Evert Bell
  • Patent number: 4046852
    Abstract: A process for purifying an impure molybdenum oxide concentrate feed material to remove therefrom the predominant portion of contaminating metals present by autoclaving at an elevated temperature under an oxygen partial pressure of at least about 100 psi, a slurry of the particulated feed material in an aqueous acid solution containing a mineral acid for a period of time sufficient to convert the predominant portion of molybdenum compounds to molybdenum trioxide and to convert the contaminating metal compounds present to aqueous acid soluble compounds. The autoclaved slurry is thereafter filtered and the solids are subjected to an aqueous alkali hydroxide leach treatment to extract the molybdenum trioxide constituent therein in the form of alkali metal molybdate compounds, which subsequently are recovered from the leach liquor in the form of a high purity alkali metal molybdate product.
    Type: Grant
    Filed: May 19, 1976
    Date of Patent: September 6, 1977
    Assignee: Amax Inc.
    Inventors: Michael A. Vertes, Richard A. Ronzio, Tommy C. Kearns
  • Patent number: 4044116
    Abstract: A method for the complete dissolution of "hard to dissolve" mineral samples, such as lunar and geological samples, wherein milligram amounts of a sample in particulate form is successively mixed while heating with small amounts of hydrofluoric acid and a mixture of sulfuric acid and distilled, demineralized water. Heating of the resulting solution is continued until its volume is reduced to about 2 milliliters after which the solution is rapidly cooled to room temperature. After adding a small amount of distilled, demineralized water, it is heated while swirling to provide a crystal clear solution. When dissolving lunar or other samples containing beryllium and chromium, an amount of a solution of sodium hydroxide is added to the crystal clear solution that is sufficient to bring the pH of the solution to about 2.5. The method makes it possible to completely dissolve mineral samples rapidly and efficiently for subsequent accurate chemical analysis.
    Type: Grant
    Filed: June 4, 1976
    Date of Patent: August 23, 1977
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Kent J. Eisentraut, Shib C. Chattoraj
  • Patent number: 4042474
    Abstract: A finely divided product containing Ni and Fe is dissolved in a sulfate-containing solvent in at least two stages and in the presence of an alkali metal and an oxidant for preciptating the Fe as alkali jarosite while Ni remains in solution which is subjected to an after-treatment. Similar processes can be used to separate cobalt and/or chromium from products containing either or both of these metals as well as iron.
    Type: Grant
    Filed: June 26, 1975
    Date of Patent: August 16, 1977
    Assignee: Pako Corporation
    Inventor: Heimo Unto August Saarinen
  • Patent number: 4040519
    Abstract: This invention relates to a froth flotation process for recovering scheelite from scheelite ores. This invention comprises adding a sulphonate collector or a mixture of a sulphonate collector and a fatty acid collector to a pulp containing the ores, selectively floating the scheelite from the ores and recovering the flotation concentrate thus obtained.
    Type: Grant
    Filed: February 20, 1975
    Date of Patent: August 9, 1977
    Assignee: Nittetsu Mining Company, Ltd.
    Inventor: Koji Fukazawa
  • Patent number: 4038363
    Abstract: Upgrading of titanium values in a slag such as Sorelslag by working up the lag such as by alkali salt roasting to render the slag leachable in a plurality of leaching stages to recover titania (and other) values of 94 to 97 percent purity useful in a sulphate or a chloride process for producing titanium dioxide.
    Type: Grant
    Filed: October 21, 1975
    Date of Patent: July 26, 1977
    Assignee: Quebec Iron & Titanium Corporation-Fer et Titane due Quebec, Inc.
    Inventor: Basil Jarish
  • Patent number: 4020143
    Abstract: A metal recovery process in which copper, nickel, cobalt and molybdenum are recovered by reducing comminuted raw manganese nodules and leaching the reduced nodules with an aqueous ammoniacal solution to obtain a leach solution containing these metal values. In order to recover copper from leach solutions by techniques such as ion exchange extraction, it is desirable to oxidize the copper to the cupric state.In another embodiment, oxidation is required to bring about the solution of reduced metallic metal values of copper, nickel and cobalt or to convert lower valence ions of these metals to a more highly oxidized state. The present invention is an improvement in the foregoing metal recovery processes. In the present invention manganese nodules are used as the oxidizing agent to oxidize slurries containing pre-reduced manganese nodules which have lower valence ions of metals such as copper or the metal itself.
    Type: Grant
    Filed: August 26, 1974
    Date of Patent: April 26, 1977
    Assignee: Kennecott Copper Corporation
    Inventors: Robert E. Lueders, Roger N. Kust, Lester J. Szabo
  • Patent number: 4018866
    Abstract: A process in which copper, nickel, cobalt and molybdenum are recovered by direct leaching of comminuted raw manganese nodules after the nodules are reduced in a reduction circuit with an aqueous ammoniacal leach solution containing cuprous ions. An improvement is disclosed which results from recycling a portion of the metal values recovered back to the reduction circuit as a solid basic metal carbonate. The metal carbonate recycle enables the size of the reactors in the reduction circuit to be reduced. The recycle also increases the efficiency of the process by facilitating the solubilization of copper. Another aspect of the invention resides in the advantages of maintaining solubilized copper in amounts between 10 grams per liter and the solubility limit in the reduction circuit.
    Type: Grant
    Filed: November 3, 1975
    Date of Patent: April 19, 1977
    Assignee: Kennecott Copper Corporation
    Inventor: Lester J. Szabo
  • Patent number: 4012484
    Abstract: A method is provided for separating chromium from lateritic ore. The ore which generally also contains nickel and cobalt along with other metal values is leached with a strong sulfuric acid solution of about 10 to 30 normal concentration at an acid to ore ratio of at least 3:1 by weight. The leaching is carried out at a temperature of at least 100.degree. C ranging as high as about 300.degree. C at above atmospheric pressure. An oxidant, such as manganese dioxide, is preferably added to oxidize the chromium to the hexavalent state, the manganese dioxide, or its equivalent, being advantageous in improving the chromium yield at the lower end of the leaching temperature range.
    Type: Grant
    Filed: September 23, 1974
    Date of Patent: March 15, 1977
    Assignee: Amax Inc.
    Inventor: Guy W. Lussiez
  • Patent number: 4006212
    Abstract: In the recovery of molybdenum and rhenium values from sulfide ores, silica impurity is reduced to low levels by adding alumina to a carbonate fusion mix in an amount sufficient to combine with the silica present to form insoluble aluminum silicates, thus preventing its removal from the fusion mass during removal of soluble molybdenum and rhenium values by leaching, and thereby avoiding the necessity for conventional subsequent precipitation and filtration removal steps.
    Type: Grant
    Filed: September 10, 1975
    Date of Patent: February 1, 1977
    Assignee: GTE Sylvania Incorporated
    Inventors: Allen Myron Alper, Carl William Boyer, Brice Eugene Martin
  • Patent number: 4005173
    Abstract: Organic acids are added to ammoniacal leach liquors containing base metals such as copper, nickel and cobalt. Ammonia and carbon dioxide are then stripped from the leach liquor by heating the leach liquor sufficiently to drive off the ammonia and carbon dioxide. The resulting loss of ammonia and carbon dioxide causes the pH of the leach liquor to drop and enables the metal values to load onto the organic acid. Metal values are selectively stripped from the loaded organic acid.
    Type: Grant
    Filed: March 3, 1975
    Date of Patent: January 25, 1977
    Assignee: Kennecott Copper Corporation
    Inventors: J. Paul Pemsler, John K. Litchfield
  • Patent number: 3999981
    Abstract: Metal values present as oxides, hydroxides or carbonates in ores or processed concentrates thereof are converted to the corresponding carbide by a solid state reaction with carbon, the carbide then is separated in substantially pure form and may be used directly as ferroalloy or may be converted to the metal.
    Type: Grant
    Filed: April 22, 1975
    Date of Patent: December 28, 1976
    Assignee: Ontario Research Foundation
    Inventor: Hans G. Brandstatter
  • Patent number: 3991156
    Abstract: A simple, efficient and economical process for purifying molybdenum disulfide concentrates by contacting and digesting the molybdenum disulfide feed material with an aqueous acid solution containing a controlled combination of hydrofluoric acid and sulfuric acid in a manner to convert substantially all of the contaminating silica bearing minerals therein to aqueous soluble fluoride and sulfate compounds and any contaminating lead sulfide compounds to lead sulfate compounds, and thereafter washing, neutralizing and drying the purified molybdenum disulfide powder product. In accordance with a preferred practice, when the molybdenum disulfide feed material contains in excess of about 0.1% iron as an indication of pyrite concentration, the concentrate is calcined at an elevated temperature in a nonoxidizing atmosphere prior to the digestion step to effect a conversion of the pyrites to synthetic pyrrhotites, which are softer and less abrasive and are more acid soluble.
    Type: Grant
    Filed: May 1, 1975
    Date of Patent: November 9, 1976
    Assignee: Amax Inc.
    Inventors: Richard A. Ronzio, Joseph G. Brown, Robert C. Ziegler
  • Patent number: 3988418
    Abstract: An improved hydrometallurgical method is provided for producing technical grade molybdic oxide from molybdenite concentrates. According to this method, the molybdenite concentrates are leached in an acid medium having a nitric acid concentration between about 25 gpl and about 50 gpl and an initial sulphuric acid concentration of nil to about 750 gpl, under oxygen pressure of about 100 - 250 psig and at a temperature above 115.degree. C so as to produce technical grade molybdic oxide having not more than 0.1% sulphur. Then a liquid-solid separation of the reaction mixture is effected and the obtained leach liquor is recycled back to the leaching stage optionally after partial neutralization with a basic reagent. The solid is washed and recovered as technical grade molybdic oxide.This invention relates to a novel method of producing hydrometallurgically technical grade molybdic oxide from molybdenite concentrates.
    Type: Grant
    Filed: August 18, 1975
    Date of Patent: October 26, 1976
    Assignee: Noranda Mines Limited
    Inventors: Derek G. E. Kerfoot, Robert W. Stanley
  • Patent number: 3988416
    Abstract: A process in which copper, nickel, cobalt and molybdenum are recovered by direct leaching of comminuted raw manganese nodules with an aqueous ammoniacal leach solution containing cuprous ions. During the process cuprous ions are consumed and are oxidized to cupric ions. The cuprous ions are regenerated by reducing the cupric ions with a reducing gas. An improvement is disclosed which results from increasing the pressure of the reducing gas. This increased pressure facilitates maintaining a high cuprous ion concentration in each reaction vessel, by increasing the rate at which the cuprous ions are regenerated from the cupric ions without affecting the rate at which the metal values are recovered from the nodules, which in turn, increases the efficiency of each reactor thus enabling the size of reactors to be reduced.
    Type: Grant
    Filed: June 13, 1974
    Date of Patent: October 26, 1976
    Assignee: Kennecott Copper Corporation
    Inventors: Herbert E. Barner, Roger N. Kust, Robert P. Cox
  • Patent number: 3983017
    Abstract: A process in which copper, nickel, cobalt and molybdenum are recovered by direct leaching of comminuted raw manganese nodules with an aqueous ammoniacal leach solution containing cuprous ions. During the process cuprous ions reduce the nodules, are consumed, and are oxidized to cupric ions. The cuprous ions are regenerated by reducing the cupric ions with a reducing gas.
    Type: Grant
    Filed: February 10, 1975
    Date of Patent: September 28, 1976
    Assignee: Kennecott Copper Corporation
    Inventor: Lester J. Szabo
  • Patent number: 3981964
    Abstract: Chrome saltcake has stable free flowing properties imparted to it by subjecting the sodium dichromate impurity present in chrome saltcake to reaction to form a product that is less susceptible to absorption of moisture than sodium dichromate.
    Type: Grant
    Filed: December 3, 1974
    Date of Patent: September 21, 1976
    Assignee: British Chrome & Chemicals Limited
    Inventor: Danvers A. Swales
  • Patent number: 3963824
    Abstract: Process of extracting chromium from a chromium ore or concentrate by oxidation, which comprises suspending the chromium ore or concentrate in a bath of molten salts and introducing an oxygen-containing gas into the suspension in a sufficient amount and for a sufficient amount of time to oxidize chromium therein.
    Type: Grant
    Filed: June 10, 1975
    Date of Patent: June 15, 1976
    Assignee: Produits Chimiques Ugine Kuhlmann
    Inventor: Roland Bachelard
  • Patent number: 3950488
    Abstract: Method for treating basic salts to preferentially extract copper without using a base to maintain the required pH. The liberation of unreacted hydrogen ions during the ion exchange reaction is eliminated by partially dissolving the basic salt mixture with an amount of acid that is equivalent to the non-copper content of the basic mixture. An amount of organic ion exchange extractant is selected so that the exchangeable hydrogen ion on the extractant is equivalent to or in excess of the amount of copper in the metal bearing liquor.
    Type: Grant
    Filed: November 4, 1974
    Date of Patent: April 13, 1976
    Assignee: Kennecott Copper Corporation
    Inventors: Roald R. Skarbo, David L. Natwig
  • Patent number: 3941867
    Abstract: Molybdenite or MoS.sub.2 materials, particularly finely divided flotation concentrates, are oxidized (roasted) to form molybdenum trioxide in a continuous composite fluidized bed containing non-elutriated refractory solids. A relatively high recycle ratio of oxidized calcine to feed is maintained for best results. The temperature of the circulated oxidized solids is maintained high to avoid sticking and deposition problems. High throughputs and high conversions have been achieved, with the product having a low sulfur content.
    Type: Grant
    Filed: September 4, 1974
    Date of Patent: March 2, 1976
    Assignee: Canadian Patents and Development Limited
    Inventors: Igor A. Wilkomirsky, Alan Paul Watkinson, J. Keith Brimacombe
  • Patent number: 3937794
    Abstract: An improved method of making finely divided, dry metal halides and sulfides, such as chromium chloride and chromium sulfide which are suitable for use as lubricants and wear-proof and corrosion-proof agents for metals.
    Type: Grant
    Filed: August 2, 1973
    Date of Patent: February 10, 1976
    Assignee: Kabushiki Kaisha Kito
    Inventors: Norio Kanetake, Ikuo Maruyama, Katsuyuki Morita
  • Patent number: 3937785
    Abstract: Method for treating solid ore residue obtained by production of chromium chemicals from chromite ore, to reduce leaching of chromium compounds therefrom after disposal, which involves reducing the particle size of the residue prior to disposal so that at least about 20 percent by weight of the residue passes through a 200 mesh (U.S.) screen.
    Type: Grant
    Filed: September 17, 1974
    Date of Patent: February 10, 1976
    Assignee: Allied Chemical Corporation
    Inventors: Alan Brian Gancy, Christian Albert Wamser
  • Patent number: 3936362
    Abstract: Ammonium tungstate, ammonium paratungstate, ammonium metatungstate or hydrated tungsten trioxide is produced by passing tungstate anions through an anion exchange membrane into an aqueous solution containing ammonium cations under the driving force of an electrical potential for a time sufficient to achieve a pH within the range in which the desired tungsten compound will form.
    Type: Grant
    Filed: June 10, 1974
    Date of Patent: February 3, 1976
    Assignee: GTE Sylvania Incorporated
    Inventors: Clarence D. Vanderpool, Martin B. MacInnis, James C. Patton, Jr.
  • Patent number: 3932598
    Abstract: An improved process for producing alkali metal chromates and dichromates wherein ferrochrome alloy containing at least 1% carbon by weight is reacted with a molten mixture of an alkali metal nitrate and an alkali metal carbonate at a temperature of at least 350.degree.C. The ferrochrome alloy can be prepared by smelting chromite ore in the presence of carbon.
    Type: Grant
    Filed: April 24, 1970
    Date of Patent: January 13, 1976
    Inventors: Hugh S. Cooper, deceased, Henry J. Rand, executor