Subjecting Mixture To Pressure, Vacuum, Or Steam Patents (Class 423/123)
  • Patent number: 9751775
    Abstract: A method comprising contacting high-purity acid, high-purity aluminum, and high-purity water to form a first solution in a heated non-contaminating vessel, wherein the aluminum is employed in at least a stoichiometric amount relative to the acid, heating the first solution in a non-contaminating container, to provide a mother liquor and solid aluminum salts, separating the solid aluminum salts from the mother liquor, heating the solid aluminum salts in a non-contaminating crucible, to provide alpha aluminum oxide, and, optionally, washing the alpha aluminum oxide with high-purity water after some or all of the heating of the solid aluminum salts to provide the alpha aluminum oxide.
    Type: Grant
    Filed: December 17, 2013
    Date of Patent: September 5, 2017
    Assignee: Polar Sapphire Ltd.
    Inventor: Scott Nichol
  • Patent number: 9382600
    Abstract: There are provided processes for preparing alumina. These processes can comprise leaching an aluminum-containing material with HCl so as to obtain a leachate comprising aluminum ions and a solid, and separating said solid from said leachate; reacting said leachate with HCl so as to obtain a liquid and a precipitate comprising said aluminum ions in the form of AlCl3, and separating said precipitate from said liquid; and heating said precipitate under conditions effective for converting AlCl3 into Al2O3 and optionally recovering gaseous HCl so-produced. These processes can also be used for preparing various other products such as hematite, MgO, silica and oxides of various metals, sulphates and chlorides of various metals, as well as rare earth elements, rare metals and aluminum.
    Type: Grant
    Filed: September 17, 2012
    Date of Patent: July 5, 2016
    Assignee: Orbite Technologies Inc.
    Inventors: Richard Boudreault, Joël Fournier, Denis Primeau, Marie-Maxime Labrecque-Gilbert
  • Publication number: 20150075328
    Abstract: There are provided processes for treating fly ash. For example, the processes can comprise leaching fly ash with HCl so as to obtain a leachate comprising aluminum ions and a solid, and separating the solid from the leachate; reacting the leachate with HCl so as to obtain a liquid and a precipitate comprising the aluminum ions in the form of AlCl3, and separating the precipitate from the liquid; and heating the precipitate under conditions effective for converting AlCl3 into Al2O3 and optionally recovering gaseous HCl so-produced.
    Type: Application
    Filed: March 11, 2013
    Publication date: March 19, 2015
    Inventors: Richard Boudreault, Joël Fournier, Denis Primeau
  • Patent number: 8628738
    Abstract: Process for manufacturing alumina trihydrate by alkaline attack of bauxite, following the general steps of the Bayer process, and during which, after settling and before decomposition, the aluminate liquor undergoes a filtration, known as security filtration, so that at the end of the filtration it contains less than 10 mg/l of insoluble particles, characterized in that, during said security filtration, a filtration device is used that comprises a zone in which the liquor is subjected, after passing through said filtration media, to a pressure greater than 2 bar, preferably greater than 3 bar. Preferably, this device also comprises a zone in which the liquor is subjected, before passing through the filtration media, to a pressure greater than 5 bar, preferably greater than 6, typically in the vicinity of 7 bar. In this way, the aluminate liquor can be kept at a high temperature during the security filtration, typically greater than 130° C., preferably greater than 140° C.
    Type: Grant
    Filed: July 29, 2009
    Date of Patent: January 14, 2014
    Assignee: Rio Tinto Alcan International Limited
    Inventors: Luc Fortin, Guy Forte, Henri Thomas, El Kadi Bassam
  • Patent number: 8268269
    Abstract: As population density increases, the transportation of hazardous chemicals, including acids and disinfectants, lead to an increased incidence of spills while the consequences of spills become more serious. While solutions of halide acids, hypohalites and halites are safer disinfectants for transportation, handling, storage and use than traditional gaseous chlorine, the manufacturing cost of these disinfectants has here-to-fore limited their use. Economical processes are presented for the manufacture of O2, halogen oxides, halide acids, hypohalites, and halates; as well as polynucleate metal compounds, metal hydroxides and calcium sulfate hydrate (gypsum). The instant invention presents methods and processes that incorporate the use of sulfur. This is while environmental regulators, such as the US EPA, require an increased removal of sulfur from hydrocarbon fuels, thereby creating an abundance of sulfur, such that the refining industry is in need of a way to dispose of said abundance of sulfur.
    Type: Grant
    Filed: July 23, 2007
    Date of Patent: September 18, 2012
    Inventors: Richard Alan Haase, John Smaardyk
  • Publication number: 20120051988
    Abstract: A process for the recovery of high purity boehmite with controlled pore size from spent hydroprocessing catalyst includes the step of treating the spent hydroprocessing catalyst composition in order to get recovery of the aluminas after extracting the valuable metals. The process permits easy and resourceful recovery of high quality boehmite from waste catalyst, which can be further used as hydroprocessing catalyst carrier having a pore structure almost identical or better than that used in heavy oil hydroprocessing catalysts. Such catalyst carrier is required to have high pore volume, macro-porosity, high strength and optimum surface area for active metal dispersion. The treating steps include process steps such as decoking, roasting, leaching, dissolving, digestion, precipitation, washing, stripping, and the like. The recovery steps include digestion, hydrothermal treatment, flocculation or precipitation, filtration, drying, calcination and the like.
    Type: Application
    Filed: August 25, 2010
    Publication date: March 1, 2012
    Inventor: Meena Marafi
  • Patent number: 8038979
    Abstract: Disclosed is a method of manufacturing a metal oxide nano powder comprising preparing a first dispersed solution by adding a nano-sized metal powder to water and dispersing the metal powder within the water, performing a hydration reaction of the first dispersed solution at a temperature of about 30 to about 70° C. to generate a precipitation, and filtering and drying the precipitation to prepare a metal oxide powder. Also, disclosed is a metal oxide nano powder manufactured by the method described above, and having any one of a bar-form, a cube-form, and a fiber-form.
    Type: Grant
    Filed: November 6, 2007
    Date of Patent: October 18, 2011
    Assignee: Korea Atomic Energy Research Institute
    Inventors: Chang Kyu Rhee, Min Ku Lee, Young Rang Uhm, Jin Ju Park, Byung Sun Han, Hi Min Lee, Seung-Hee Woo
  • Patent number: 7922996
    Abstract: This invention relates to novel compositions of zeolites or microporous metallosilicates characterized by a continuous spatial distribution of the metal and silicon in the crystals and characterized by a crystal surface enriched in silicon relative to the internal part of the same crystals. This invention also relates to a synthesis method of producing these metallosilicates with spatial distribution of the constituting elements. These novel zeolitic compositions can be used in various hydrocarbon conversion reactions. The crystalline metallosilicates can be selected from the group consisting of aluminosilicates, gallosilicates, ferrosilicates, titanosilicates and borosilicates.
    Type: Grant
    Filed: November 25, 2005
    Date of Patent: April 12, 2011
    Assignee: Total Raffinage Marketing
    Inventors: Walter Vermeiren, Jean-Pierre Dath, Valérie Buono
  • Patent number: 7922995
    Abstract: This invention relates to novel compositions of zeolites or microporous metallosilicates characterized by a continuous spatial distribution of the metal and silicon in the crystals and characterized by a crystal surface enriched in silicon relative to the internal part of the same crystals. This invention also relates to a synthesis method of producing these metallosilicates with spatial distribution of the constituting elements. These novel zeolitic compositions can be used in various hydrocarbon conversion reactions. The crystalline metallosilicates can be selected from the group consisting of aluminosilicates, gallosilicates, ferrosilicates, titanosilicates and borosilicates.
    Type: Grant
    Filed: November 25, 2005
    Date of Patent: April 12, 2011
    Assignee: Total Raffinage Marketing
    Inventors: Walter Vermeiren, Jean-Pierre Dath, Valérie Buono
  • Patent number: 7807119
    Abstract: A process for the production of alumina trihydrate by alkaline digestion of bauxite using the Bayer process in which aluminate liquor and insoluble residues are separated using a solid/liquid separation device (E; W2; DC) characterised in that the said slurry (21a; 41; 230?) is at least partially passed through a hydrocyclone (H1; H21; H22; H3) to improve and accelerate the separation of the sodium aluminate liquor from the insoluble residues in the slurry (21a; 41; 230?) containing the said liquor and the said residues and that supplies or is derived from the said liquid-solid separation device. In a first embodiment, at least one hydrocyclone is used at the upstream side of the settler-thickener, as clarifier of the pregnant liquor. In a second embodiment, at least one hydrocyclone is used as a thickener of insoluble residue mud. In a third embodiment, a hydrocyclone is used in combination with the causticisation settler.
    Type: Grant
    Filed: September 19, 2005
    Date of Patent: October 5, 2010
    Assignee: Aluminium Pechiney
    Inventors: Jean-Marc Rousseaux, Gerard Pignol, Yves Magnan
  • Patent number: 7288241
    Abstract: A black composite oxide particle includes a composite oxide having Fe, Mg and Al as metal components. The particle contains Fe, Mg and Al in amounts of 30 to 55 mass %, 1 to 10 mass %, and 1 to 10 mass %, respectively, and has an atomic ratio of Fe3+/Fe2+ of 0.8 to 10. Also described is a method for producing the black composite oxide particle. In an embodiment, the particle includes a hydrated composite oxide represented by an empirical formula: Fe2+aFe3+bMgcAldOe·nH2O. The black composite oxide particle is suitable as a black pigment for a coating material, an ink, toner particles, a rubber and a plastic, and is reduced with respect to the load on the environment and excellent in blackness.
    Type: Grant
    Filed: December 12, 2002
    Date of Patent: October 30, 2007
    Assignee: Mitsui Mining and Smelting Co., Ltd.
    Inventors: Koji Aga, Hiroyuki Shimamura
  • Patent number: 7052798
    Abstract: The present invention concerns a device for mounting a source of electric energy (100), preferably a button-type battery, for a portable electronic apparatus including a housing (3, 44), closed by a cover (14, 49), for said energy source. The housing includes, in proximity to its periphery, tongues (5, 32) that can be deformed for holding the energy source axially in the housing. Further, the cover includes a wall (15, 50) projecting into the housing and arranged between the periphery of the housing and the tongues retaining the energy source. The wall of the cover thus ensures that the tongues are held properly against the energy source when the latter is arranged in the housing, in particular in the event of a violent shock.
    Type: Grant
    Filed: December 11, 2003
    Date of Patent: May 30, 2006
    Assignee: ETA SA Manufacture Horlogere Suisse
    Inventors: Laurent Kaelin, Fabien Henriet, Jean-Philippe Rebeaud
  • Patent number: 6616902
    Abstract: A process is disclosed for the treatment of an alumina process feedstock prior to transferring the treated feedstock to an alumina process for extracting refined alumina from the treated feedstock. The treatment process includes the following steps: (a) heating the alumina process feedstock to a temperature of 400C. to 650C. by direct contact with combustion gases, and (b) cooling the heated feedstock to a temperature at which it can be handled and fed to the alumina process. The treatment process is characterised by controlling the contact time of the solid alumina process feedstock at temperatures in the above range in step (a) to less than 5 minutes.
    Type: Grant
    Filed: April 25, 2001
    Date of Patent: September 9, 2003
    Assignee: Comalco Aluminium Limited
    Inventors: Michael Hollitt, Stephen Grocott, Gerard Roe
  • Patent number: 6582670
    Abstract: A process is provided for the treatment of an alumina process feedstock prior to transferring the treated feedstock to an alumina process for extracting refined alumina from the treated feedstock. The treatment process includes: (a) heating the alumina process feedstock to a temperature of 400° C. to 650° C. by direct contact with combustion gas, and (b) cooling the heated feedstock to a temperature at which it can be handled and fed to the alumina process. The treatment process also includes controlling the contact time of the alumina process feedstock at temperatures in step (a) to ensure decomposition of alumina trihydrate and alumina monohydrate. The process also includes: (i) limiting the maximum temperature of incoming gas to a stage of the process in which the alumina process feedstock reaches the above temperature range of 400° C. to 650° C.
    Type: Grant
    Filed: June 18, 2001
    Date of Patent: June 24, 2003
    Assignee: Comalco Aluminum Limited
    Inventors: Michael Hollitt, Stephen Grocott, John Peter Kisler, Colin John Beeby
  • Patent number: 6555076
    Abstract: The process according to the invention to raise simultaneously to an optimum level the temperature and concentration of an aqueous medium intended for use in bauxite ore digestion in an alumina production plant according to the Bayer process, which includes successive phases (a) to (f) in which: a) the aqueous medium coming from digestion containing pregnant liquor is cooled and evaporated in a multiple staged flash evaporation zone; b) the sterile residue is separated, the aluminium trihydroxide is precipitated and the aqueous medium, consisting of spent liquor, intended for use in digestion is recovered; c) if need be, the required quantity of water, additional to that already evaporated in phase (a) is eliminated by evaporation in a specific evaporation section; d) the aqueous medium intended for use in digestion is heated in several stages; e) the flash vapour generated in each of the stages of the evaporation phase (a) is used in each of the stages of the heating phase (d); f) the aqueous medium in
    Type: Grant
    Filed: September 22, 2000
    Date of Patent: April 29, 2003
    Assignee: Gea Kestner
    Inventors: Bernard Droy, Dany Michaux
  • Patent number: 6004519
    Abstract: The recovery of aluminum chloride from deactivated alkylation catalyst complexes by hydrogenation using hydrogen gas and an aluminum catalyst is disclosed. Using aluminum to catalyze the hydrogenation allows the reaction to proceed at a lower temperature and pressure while reducing the amount of hydrogen chloride present in the reactor thus reducing the corrosiveness and cost of the aluminum chloride recovery. Methods for batch, batchwise continuous, and continuous aluminum chloride recovery are disclosed.
    Type: Grant
    Filed: January 2, 1997
    Date of Patent: December 21, 1999
    Assignee: Kerr-McGee Corporation
    Inventors: Elliott P. Doane, Jim Yuen-Fong Low, Larry G. Sherman, William A. Yuill
  • Patent number: 5997828
    Abstract: A process for extraction of alumina from ore bodies containing aluminum is disclosed. The process comprises the steps of acid leaching an aluminum bearing ore to produce a leach liquor that includes aluminum values and silicon values. Any ferrous sulfate in the leach liquor is oxidized with an oxidizing agent comprising ozone to ferric sulfate. The oxidized leach liquor is hydrolyzed at about 130.degree. C. to form a gel of ferric values which are then removed. Any ferric sulfate remaining in the leach liquor after hydrolyzing is reduced to ferrous sulfate. The reduced leach liquor is then hydrolyzed at 165-180.degree. C. to remove precipitated basic aluminum alkali sulfate. The basic aluminum alkali sulfate is then dried and calcined at around 950.degree. C. to produce alumina and alkali sulfate which releases any SO.sub.2 and any SO.sub.3. The alumina is washed to remove any alkali sulfate and the washed alumina is then agglomerated and dried.
    Type: Grant
    Filed: September 30, 1998
    Date of Patent: December 7, 1999
    Inventor: John S. Rendall
  • Patent number: 5902560
    Abstract: A new and improved method for inhibiting the precipitation of sodium oxalate crystals in a Bayer process liquor is provided. In an embodiment, the method comprises the step of adding to the Bayer process liquor, after red mud separation, a minor effective amount of a liquor oxalate stabilizer selected from hydrocarbon-substituted amine oxide compounds and/or hydrocarbon-substituted betaine compounds.
    Type: Grant
    Filed: August 28, 1997
    Date of Patent: May 11, 1999
    Assignee: Nalco Chemical Company
    Inventor: Graeme J. Farquharson
  • Patent number: 5885536
    Abstract: A process for alkaline leaching of a titaniferous material containing silica and alumina impurities in which spent leachant is recycled by treating to remove the silica and alumina impurities therefrom, by heating, maintaining the leachant at leaching temperature, or treating with an additive. The removal of the silica and alumina impurities by the method of the invention enables further use of the leachant.
    Type: Grant
    Filed: January 6, 1997
    Date of Patent: March 23, 1999
    Assignee: Technological Resources Pty Ltd
    Inventor: Michael John Hollitt
  • Patent number: 5869020
    Abstract: Process for the production of aluminium hydroxide by digesting bauxite with alkali solution and precipitating aluminium hydroxide from the digestion solution, comprising:a combining bauxite and alkali solution having a caustic concentration of at least 180 grams per liter expressed as sodium carbonate and digesting partly the bauxite in the combined product in a first digestion step at relatively low temperature,b separating reaction product obtained in step a into a liquid phase and a solids/liquid slurry,c combining liquid phase and solids/liquid slurry obtained in step b and digesting the combined product in a second digestion step at relatively high temperature,d releasing heat from the reaction product obtained in step c to preheat liquid phase obtained in step b,e separating the reaction product obtained in step d into a supersaturated sodium aluminate solution and undissolved material,f precipitating aluminium hydroxide from the supersaturated sodium aluminate solution obtained in step e and separating
    Type: Grant
    Filed: April 22, 1992
    Date of Patent: February 9, 1999
    Assignee: Shell Internationale Research Maatschappij B.V.
    Inventors: Albert Rijkeboer, Roelof Den Hond
  • Patent number: 5795559
    Abstract: A method for the preparation of new semi-crystalline, porous inorganic oxide compositions possessing uniform framework-confined mesopores in the range 2.0-10.0 nm. The method uses an interaction between various nonionic polyethylene oxide based surfactants (N.degree.) and neutral inorganic oxide precursors (I.sup..quadrature.) at ambient reaction temperatures. The materials formed exhibit a disordered assembly of worm-like channels of regular diameter owing to the specific mechanism of self-assembly, producing highly stable materials and particles incorporating large numbers of the channels. This (N.degree. I.degree.) templating approach introduces several new concepts to mesostructure synthesis. The application of the low-cost, non-toxic and biodegradable surfactants and ambient reaction temperatures, introduces environmentally clean synthetic techniques to the formation of mesostructures. Recovery of the template can be achieved through solvent extraction where the solvent may be water or ethanol.
    Type: Grant
    Filed: May 2, 1996
    Date of Patent: August 18, 1998
    Assignee: Board of Trustees operating Michigan State University
    Inventors: Thomas J. Pinnavaia, Stephen A. Bagshaw
  • Patent number: 5720868
    Abstract: A method of making activated alumina includes beginning with a leach liquor of potassium and aluminum sulphates that is subjected to a surface-cooled crystallizer with a heat-exchanger input temperature of 160.degree. F. and a surface-chilled temperature of 60.degree. F. Crystals of aluminum sulphate are precipitated and recrystalized by evaporation in a vacuum and at an elevated temperature. Purified crystals of aluminum sulphate are then dried at 50.degree.-60.degree. C. The dried aluminum sulphate crystals are then dehydrated at 400.degree.-450.degree. C. after a rise rate of 50.degree.-60.degree. C. per minute to drive off most of the water. A roasting and recalcination step at 1000.degree. C.-1050.degree. C. after a rise rate of 50.degree.-60.degree. C. per minute is used drive off the sulphate. The remaining alumina is smelted by electrolysis for aluminum.
    Type: Grant
    Filed: April 19, 1996
    Date of Patent: February 24, 1998
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar, Stephen J. Lane
  • Patent number: 5545384
    Abstract: A process for the production of aluminum hydroxide from an alumina-containing ore comprising, in a process for the production of aluminum hydroxide involving extraction of alumina from an alumina-containing ore by an aqueous alkaline solution, supplying a slurry containing the alumina-containing ore at a high solid content which is prepared from a small amount of an alkaline solution together with an aqueous alkaline solution which is so preheated to a temperature that a preheated temperature is enough high to have a temperature after the mixing with the slurry which is higher than an extraction temperature of alumina, simultaneously or after the mixing them, to an extraction apparatus comprising of a tube reactor, extracting alumina from the alumina-containing ore under extraction conditions of a temperature of 120.degree.-160.degree. C.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: August 13, 1996
    Assignee: Sumitomo Chemical Co., Ltd.
    Inventors: Takuo Harato, Takahiro Ishida, Yoshio Kumagae, Michikazu Inami, Kazuhisa Ishibashi, Mitsuaki Murakami
  • Patent number: 5436088
    Abstract: A battery cradle (130) is provided for securing a battery (117)within a battery compartment (120). The battery cradle (130) includes a frame member (131) having a cavity (141) to receive the battery (117). The frame member (131) is formed to fit a portion of the battery compartment (120) and has a peripherally located seal (146) to seal the battery compartment (120).
    Type: Grant
    Filed: May 2, 1994
    Date of Patent: July 25, 1995
    Assignee: Motorola, Inc.
    Inventors: Julio C. Castaneda, Stuart A. Heilsberg, Joseph R. Rauch
  • Patent number: 4994253
    Abstract: A process for the production of large boehmite crystal aggregates, useful for soft polishing applications is provided herein. A caustic aluminate liquor is contacted with an oxygen-containing gas at elevated temperatures and pressures in the presence of about 1-50 mg/L of copper ions. The liquor is oxidized until a molar ratio of Na.sub.2 O.sub.free to Al.sub.2 O.sub.3 of less than or equal to 1 is achieved, and the oxidized liquor is cooled under quiescent conditions of little or no agitation which causes the crystallization and precipitation or novel large boehmite particles.
    Type: Grant
    Filed: August 30, 1988
    Date of Patent: February 19, 1991
    Assignee: Vereinigte Aluminium-Werke AG
    Inventor: Neil Brown
  • Patent number: 4861371
    Abstract: A nickel-containing ore is leached with sulfuric acid to dissolve nickel and associated metallic values into the sulfuric acid to form a leachate, the sulfuric acid further containing a source of the monovalent cations sodium, potassium or ammonium to suppress solubilization of aluminum ions in the ore. The leaching process is conducted at elevated temperatures of from about 200.degree. C. to about 300.degree. C., and at elevated pressures. In such leaching process, the monovalent cations are present in the leaching liquid prior to the initiation of leaching, to achieve an aluminum content of the leachate of less than about 0.5 grams per liter.
    Type: Grant
    Filed: December 28, 1988
    Date of Patent: August 29, 1989
    Assignee: California Nickel Co.
    Inventor: Harris Lowenhaupt
  • Patent number: 4853205
    Abstract: Process of using supercritical fluid to selectively separate, purify and recover metal halides.
    Type: Grant
    Filed: March 12, 1987
    Date of Patent: August 1, 1989
    Assignee: The United states of America as represented by the Secretary of the Interior
    Inventors: William K. Tolley, Alton B. Whitehead
  • Patent number: 4769351
    Abstract: A process for preparing a zirconia-alumina base composite ultra-fine powder is described, including the steps of: mixing an aluminum salt or an alumina hydrate with an aqueous zirconium oxychloride solution, with or without metal salt acting as a stabilizer; mixing urea or a substance capable of generating ammonia by hydrolysis with the resulting mixture; and allowing the mixture to react at a temperature of 140.degree. to 300.degree. C. and a pressure of 4 to 150 kg/cm.sup.2 in a high-temperature and -pressure vessel. The reaction product is further dried, calcined and crushed to obtain an ultra-fine powder.
    Type: Grant
    Filed: May 4, 1987
    Date of Patent: September 6, 1988
    Assignees: Chichibu Cement Co., Ltd., Shigeyuki Soumiya
    Inventors: Shigeyuki Soumiya, Masahiro Yoshimura, Zenjiro Nakai, Kazumitsu Hishinuma, Takao Kumaki
  • Patent number: 4729881
    Abstract: Beryllium is efficiently recovered from silicate ores in a hydrometallurgical, single solvent, process which avoids the complexities, high costs and hazards ofpyrolytic, fluorination and acid leach methods, by contacting the ore in a closed reactor at elevated temperature and autogenous pressure with a concentrated caustic solution and lime or lime hydrate to form a slurry containing dissolved beryllium, reducing the pressure to about one atmosphere and the temperature to below the boiling point of the caustic solution, separating by-product solids to leave a pregnant leach liquor, diluting and digesting the leach liquor to precipitate the beryllium and to leave a caustic mother liquor, and separating the beryllium. The caustic mother liquor can be recycled to the ore contacting step in a closed loop version of the process.
    Type: Grant
    Filed: December 16, 1986
    Date of Patent: March 8, 1988
    Assignee: FMC Corporation
    Inventor: William C. Copenhafer
  • Patent number: 4647439
    Abstract: A process for the continuous production of alumina by means of the Bayer process by alkaline attack in reactors on bauxites which primarily consist of aluminum monohydrates and contain silica in a free state or combined in the form of aluminum silicate, the essential aim of which is to delay scaling of the reactors by deposits of sodium silico-aluminate on the reactor walls. The process comprises the following steps: (1) the bauxite is put into suspension by crushing in a sodic liquor (aqueous solution of caustic soda); (2) the suspension is raised to a temperature of from 90.degree. to 108.degree. C. and held at that temperature for a period of time sufficient to convert at least 75% of the aluminum silicate contained in the bauxite into insoluble sodium silico-aluminate; (3) The suspension is then subjected to steam heating by passing through a tube-type heat exchanger under pressure at a temperature which is at least equal to 160.degree. C. and preferably is from 160.degree. to 230.degree. C.
    Type: Grant
    Filed: May 19, 1986
    Date of Patent: March 3, 1987
    Assignee: Aluminium Pechiney
    Inventor: Jean Lepetit
  • Patent number: 4617179
    Abstract: The invention concerns a process for the precipitation of aluminium hydroxide by seeding in two phases, which is intended to produce at a high level of productivity alumina with large grains, referred to as `sandy coarse`, by precipitation in a succession of tanks in cascade relationship of a supersaturated solution of sodium aluminate coming from alkaline attack on bauxite in accordance with the BAYER process. The process comprises three stages:in the first agglomeration stage, the supersaturated aluminate liquor is introduce into the tank, with an equivalent amount of terms of Na.sub.2 O of between 110 and 175 g/liter, at a temperature of between 65.degree. and 80.degree. C.
    Type: Grant
    Filed: November 19, 1985
    Date of Patent: October 14, 1986
    Assignee: Aluminium Pechiney
    Inventor: Maurice Veyrier
  • Patent number: 4548794
    Abstract: According to the present invention, processes are provided for recovery of nickel, cobalt and like metal values from laterite ores wherein the ores are separated into high and low magnesium containing fractions, the low magnesium fraction is leached with sulfuric acid at elevated temperatures and pressure to solubilize the metal values. The pregnant liquor resulting from the high pressure which also contains solubilized Fe, Al and acid is then contacted with a low magnesium fraction of the ore in a low pressure leach under conditions such that at least some of the acid is neutralized and substantially all of the solubilized Fe and Al is removed as hematite and alunite precipitate.In one embodiment, the pregnant liquor from the high pressure leach and the high magnesium fraction are contacted at atmospheric pressure and a temperature of about 80.degree. C. prior to low pressure leaching. In other embodiments, various process streams are separated by size and otherwise, and recycled to within the processes.
    Type: Grant
    Filed: July 22, 1983
    Date of Patent: October 22, 1985
    Assignee: California Nickel Corporation
    Inventors: E. Harris Lowenhaupt, John E. Litz, Dennis L. Howe
  • Patent number: 4541994
    Abstract: According to the present invention, Ni- and Co-rich, low Mg fines may be advantageously separated from the coarse fractions of lateritic ores by atmospheric or low pressure leaching. In particular, the process of the present invention comprises contacting a lateritic ore or ore fraction at temperatures from about 20.degree. C. to about 200.degree. C. and pressures from about atmospheric to about 200 psig with an aqueous acid solution to form a leach liquor, a leach residue and a fines fraction. The fines fraction which can be separated from the residue with the leach liquor by conventional means such as cycloning is found to be richer in Ni and Co and lower than the remainder of the residue.
    Type: Grant
    Filed: July 22, 1983
    Date of Patent: September 17, 1985
    Assignee: California Nickel Corporation
    Inventors: E. Harris Lowenhaupt, John E. Litz, Dennis L. Howe
  • Patent number: 4483830
    Abstract: A process for recovery of alumina and soda from materials containing sodium aluminosilicates, such as red mud and desilication products, comprises treating said materials with lime at elevated temperature and pressure. In a preferred embodiment of the invention, hydrothermal treatment of red mud with lime is integrated into a Bayer process to improve the overall efficiency of that process.
    Type: Grant
    Filed: September 3, 1982
    Date of Patent: November 20, 1984
    Assignee: Comalco Limited
    Inventors: Pearson J. Cresswell, David J. Milne
  • Patent number: 4415542
    Abstract: The scaling of autoclave and leaching-equipment surfaces during the high pressure leaching of nickeliferous oxide and silicate ores is controlled during leaching to favor the formation of scale containing substantial amounts of magnesium sulfate that is more easily removed by chemical dissolution using water or dilute sulfuric acid at temperatures ranging from about 50.degree. C. to 250.degree. C. than scale containing substantial amounts of alunite.
    Type: Grant
    Filed: June 21, 1982
    Date of Patent: November 15, 1983
    Assignee: Compagne Francaise D'Entreprises Minieres, Metallurgiques et D'Investissements
    Inventors: Paul B. Queneau, Robert E. Doane, Mark H. Berggren, Mark W. Cooperrider
  • Patent number: 4394368
    Abstract: Aqueous aluminum sulfate solution is hydrolyzed at temperatures above about 300.degree. C. to produce a basic aluminum sulfate product that is readily purified and converted to Al.sub.2 O.sub.3.
    Type: Grant
    Filed: December 4, 1981
    Date of Patent: July 19, 1983
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventor: Donald E. Shanks
  • Patent number: 4305913
    Abstract: A precipitation system is provided for the production of strong, coarse alumina hydrate (Al.sub.2 O.sub.3.3H.sub.2 O) from Bayer process aluminate liquors. In the system three distinct, but interconnected processing stages are utilized which comprise an agglomeration stage, a growth stage and a seed generation stage. In the agglomeration stage hydrate particles agglomerate to form coarse particles; in the growth stage these particles grow and acquire strength; while in the seed generation stage alumina hydrate seed is generated to be used in the agglomeration and growth stages.The precipitation system combines the advantages of both the American and European Bayer processes in that it results in the production of a strong, coarse product hydrate and an increased yield.
    Type: Grant
    Filed: August 6, 1980
    Date of Patent: December 15, 1981
    Assignee: Kaiser Aluminum & Chemical Corporation
    Inventor: Joseph L. Anjier
  • Patent number: 4282190
    Abstract: A process for the removal of iron and aluminum values from acidic solutions thereof with zinc chloride wherein the solution is subjected to pressure hydrolysis to precipitate the iron and aluminum as the hydroxides or oxide hydrates, and then the precipitate is removed and washed. Zinc chlorides which are particularly free from iron and aluminum can be rapidly and easily obtained with this process.
    Type: Grant
    Filed: November 8, 1979
    Date of Patent: August 4, 1981
    Assignee: Th. Goldschmidt AG
    Inventors: Wolfgang Muller, Lothar Witzke
  • Patent number: 4260589
    Abstract: Aluminum nitrate solutions are subjected to hydrolysis at elevated temperature and pressure, with the pressure being kept relatively low by continual bleeding of reactant gases from the reaction vessel. The resultant product is a noncrystalline alumina that may be readily converted to crystalline alumina by roasting.In addition, the discharged reactant gases are employed for leaching of clay to provide aluminum nitrate feed solution.
    Type: Grant
    Filed: July 10, 1979
    Date of Patent: April 7, 1981
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventors: Barlane R. Eichbaum, Judith A. Eisele, Donald J. Bauer
  • Patent number: 4244928
    Abstract: The invention concerns a process for sulfuric acid treatment of clays or aluminiferous minerals to obtain pure aluminum oxide via a basic intermediate. The process finds application in the production of aluminum through fusion electrolysis and for the production of different types of alumina. The process provides a mass production method which is economically and technically superior over the prior art methods.The mechanically and/or thermally pretreated raw material is subjected to a two-step pressure treatment with sulfuric acid solution. The aluminum sulfate solution is treated to reduce the iron with SO.sub.2 and hydrolytic precipitation of basic aluminum sulfates. After separation of the salts from the mother liquor, which is returned to the process, the aluminum sulfate is thermally decomposed. The SO.sub.2 /SO.sub.3 -containing waste gases from the decomposition are used to renew the treatment acid.
    Type: Grant
    Filed: June 8, 1979
    Date of Patent: January 13, 1981
    Assignee: VEB Mansfeld Kombinat William Pieck
    Inventors: Siegfried Ziegenbalg, Gerhard Haake, Gunter Geiler
  • Patent number: 4243429
    Abstract: A lime material and a siliceous material containing 10 to 40% by weight of alumina are admixed with an alkali solution, and the mixture is subjected to hydrothermal reaction with saturated water vapor at 4 to 40 kg/cm.sup.2 to form tobermorite. The reaction mixture is filtered to separate the tobermorite therefrom. A lime material and a gypsum material are added to the resulting filtrate, and the mixture is reacted at room temperature to a temperature of 90.degree. C. to form ettringite. The alkali filtrate separated from the ettringite is reused for the production of tobermorite.
    Type: Grant
    Filed: June 22, 1979
    Date of Patent: January 6, 1981
    Assignee: Kubota Ltd.
    Inventors: Hideo Tamura, Seiro Ibuki
  • Patent number: 4238458
    Abstract: The process of the present invention resides in the production of an extremely pure basic aluminum-sodium carbonate of the dawsonite type. In the process of the present invention, aluminum hydroxide is reacted with an aqueous sodium bi-carbonate solution at a temperature between 160.degree. and 240.degree. C. and at a pressure of 5-50 atm. The reagents from an aqueous suspension which is stirred throughout the duration of the reaction and the temperature of the reaction is chosen in accordance with the length of crystalline fiber which is to be produced.
    Type: Grant
    Filed: February 1, 1978
    Date of Patent: December 9, 1980
    Assignee: Swiss Aluminium Ltd.
    Inventor: Chanakya Misra
  • Patent number: 4224288
    Abstract: In a process for the production of alumina which comprises the steps of digesting bauxite to produce a precipitate of alumina trihydrate containing uncombined moisture, drying the alumina trihydrate to reduce the uncombined moisture content thereof, and feeding the dried alumina trihydrate to a calciner to convert the alumina trihydrate to alumina, improved economy is achieved by drying the alumina trihydrate in a fluidized bed in which the fluidized mass is heated indirectly by means of steam which is available from the digestion and recovery system. Drying of the alumina trihydrate in this manner prior to feeding it to the calciner also reduces the fuel requirement in the calciner and enables the throughput of the calciner to be increased.
    Type: Grant
    Filed: February 6, 1979
    Date of Patent: September 23, 1980
    Assignee: Monash University
    Inventor: Owen E. Potter
  • Patent number: 4215094
    Abstract: In the production of alumina from bauxite by the Bayer process, the present invention provides an improvement for effectively and economically removing organic substances from a circulating alkali aluminate solution by contacting the aluminate solution containing organic substances with molecular oxygen gas or a molecular oxygen-containing gas in the presence of copper ions as a catalyst at an elevated temperature, thereby oxidizing the organic substances, adding a chemical substance to the resulting aluminate solution which reacts with copper ions to deposit a water-insoluble precipitate, and separating the precipitate from the solution, and recycling the precipitate as a copper source to the above-mentioned wet oxidation procedure.
    Type: Grant
    Filed: February 12, 1979
    Date of Patent: July 29, 1980
    Assignee: Sumitomo Aluminum Smelting Company, Ltd.
    Inventors: Jun-ichi Inao, Koichi Yamada, Takuo Harato, Hisakatsu Kato
  • Patent number: 4112047
    Abstract: A pretreatment system is provided for transforming the goethite constituent [FeO(OH)] of goethitic bauxites to hematite and/or magnetite at high temperatures and pressures. The system employs a number of float-type, liquid displacement pressure pumps, both for charging caustic-containing bauxite slurries of high solids concentration to the system and for discharging the treated slurries. The system operates at temperatures in excess of 250.degree. C and up to temperatures required for the total conversion of the goethite content to hematite or magnetite which, in turn, significantly increases the yield of recoverable alumina. Since the slurry to be pretreated is of high solids concentration, e.g.
    Type: Grant
    Filed: June 8, 1977
    Date of Patent: September 5, 1978
    Assignee: Kaiser Aluminum & Chemical Corporation
    Inventor: Donald J. Donaldson
  • Patent number: 4094955
    Abstract: Alumina monohydrate is produced by leaching calcined clay and subjecting the leach liquor to pressure hydrolysis wherein the vapor and heat resulting from the pressure hydrolysis are directly utilized for leaching of the calcined clay. The aluminum monohydrate may be roasted to yield alumina.
    Type: Grant
    Filed: June 24, 1977
    Date of Patent: June 13, 1978
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventors: Donald J. Bauer, Judith A. Eisele, Barlane R. Eichbaum
  • Patent number: 4058542
    Abstract: A monovalent thallium compound is converted to a trivalent thallium compound by treating the thallium (I) compound with molecular oxygen in the presence of a Group VIII noble metal catalyst and in the presence of a promoter comprising a heterocyclic tertiary amine to oxidize the thallium (I) compound to a thallium (III) compound.
    Type: Grant
    Filed: November 8, 1976
    Date of Patent: November 15, 1977
    Assignee: Halcon International, Inc.
    Inventors: Nabil Rizkalla, Anthony N. Naglieri
  • Patent number: 4031182
    Abstract: A process for recovering aluminum from alunite ore directed to providing a residue for the Bayer leach step substantially free of impurities so that a high A/C ratio Bayer leach liquor is produced, which comprises roasting the ore in particulate form to drive off water and sulfur as SO.sub.2 and to convert aluminum sulfate to alumina, leaching the residue containing aluminum values with water and filtering to remove potassium sulfate and other soluble sulfates, hot leaching the residue with sulfuric acid to convert the alumina therein to soluble aluminum sulfate followed by filtering to remove silicon dioxide and other solid impurities, crystallizing the aluminum sulfate to further remove impurities, heating the residue to convert the aluminum sulfate to alumina and drive off any remaining sulfur as SO.sub.2, and digesting the alumina calcine with sodium hydroxide under standard Bayer conditions at a high A/C ratio to provide a high A/C ratio solution from which a "sandy" aluminum hydroxide is precipitated.
    Type: Grant
    Filed: March 24, 1976
    Date of Patent: June 21, 1977
    Assignees: Southwire Company, National Steel Corporation, Earth Sciences, Inc.
    Inventor: Kent W. Loest