Hydroxylating Or Hydrating Patents (Class 423/127)
  • Patent number: 7022305
    Abstract: Nanoscale corundum powders are obtained by first producing an Al2O3 precursor by adding seed crystals to an aqueous solution of an aluminium compound and adding a base and then converting the Al2O3 precursor into corundum by calcination at a high temperature. Before the calcination, the salts that are present in addition to the Al2O3 precursor are separated off. The resulting product is calcined at temperatures of 700 to 975° C. and any fines that may be present are removed. The resulting corundum powders can be sintered at temperatures of ?1200° C. to produce compacts or components of multiple layer systems.
    Type: Grant
    Filed: July 20, 2001
    Date of Patent: April 4, 2006
    Assignee: Leibniz-Institut fuer neue Materialien Gemeinnuetzige GmbH
    Inventors: Robert Drumm, Christian Goebbert, Kai Gossmann, Ralph Nonninger, Helmut Schmidt
  • Patent number: 6887454
    Abstract: Gibbsite type aluminium hydroxides are obtained by seeding a Bayer liquor with bayerite crystals. The gibbsite type aluminium hydroxide show excellent properties as fire retardant fillers in synthetic resins.
    Type: Grant
    Filed: June 27, 2000
    Date of Patent: May 3, 2005
    Assignee: Albemarle Corporation
    Inventors: Genoveva Bilandzic, Neil Brown, Norbert Putz
  • Patent number: 6835228
    Abstract: A process of recovering metals from waste lithium ion/Ni—H/Ni—Cd batteries, wherein the waste batteries are calcined and sieved to generate an ash containing metals and metal oxides. The process includes subjecting the ash to a first dissolution etching treatment, a first filtration treatment to obtain a filtrate containing Cd ions which are crystallized as cadmium sulfate, a second dissolution etching treatment for the filtered solid, and a second filtration treatment to obtain a second filtrate. Fe+3, Al+3 and rare earth metal ions in the second filtrate are precipitated as hydroxides by adding a base to the second filtrate. The remaining solution was extracted and counter-extracted to obtain aqueous solutions of Co and Ni ions, which were subjected separately to a electrolysis to deposit Co and Ni metals. Li ions in the residue solution from the electrolysis of Ni was precipitated as carbonate by adding a soluble carbonate salt.
    Type: Grant
    Filed: November 19, 2003
    Date of Patent: December 28, 2004
    Assignee: Industrial Technology Research Institute
    Inventors: Jiunn-Ren Lin, I-Long Chang, Yu-Lin Jiang, Jer-Yuan Shiu
  • Patent number: 6827923
    Abstract: Aluminium hydroxide of high whiteness is produced by (i) heating aluminium hydroxide obtained from the Bayer process to a temperature of 300 to 700° C. (ii) dissolving the soluble fraction of the thus obtained activated product at 85 to 275° C. in aqueous sodium hydroxide to form a sodium aluminate liquor containing an undissolved residue of very fine boehmite, (iii) filtering said sodium aluminate liquor to obtain a clear solution of sodium aluminate supersaturated with respect to dissolved alumina, (iv) cooling said clear solution to 50 to 80° C. and seeding with crystallized aluminium hydroxide to induce further crystallization, and (v) separating, washing and drying the produced aluminium hydroxide crystals.
    Type: Grant
    Filed: June 4, 2002
    Date of Patent: December 7, 2004
    Assignee: Albemarle Corporation
    Inventor: Neil Brown
  • Patent number: 6814947
    Abstract: The invention relates to the production of calcium compounds containing water of crystallization by means of a chemical reaction between an aqueous alkaline sodium aluminate solution and solid or dissolved or suspended calcium (hydr)-oxide in the presence of carbon dioxide or carbonate; and to the use of these compounds. The resulting precipitate is separated by sedimentation, dehydration, drying and/or clacination and/or grinding or suspending the resulting filter cake and reacted with at least one mineral acid and/or at least one salt of the same. The resulting precipitate, which contains water of crystallization, is separated by sedimentation, dehydration, drying and/or grinding.
    Type: Grant
    Filed: November 29, 2001
    Date of Patent: November 9, 2004
    Assignee: Rethmann Lippewerk GmbH
    Inventors: Josef Lehmkuhl, Ansgar Fendel, Hubert Bings
  • Patent number: 6800260
    Abstract: Processes for treating iron containing waste streams are provided. According to these processes, metal-containing compounds, particularly iron oxides are produced. These methods may, for example, be used in the processing of the waste streams from the chlorination of titanium-bearing raw materials and involve the use of certain combinations of neutralization and precipitation steps.
    Type: Grant
    Filed: February 11, 2002
    Date of Patent: October 5, 2004
    Assignee: Millennium Inorganic Chemicals, Inc.
    Inventors: Peter Carter, Christopher John Davis, Michael Robinson, Kirit Talati
  • Patent number: 6676910
    Abstract: An improved process for the causticisation of Bayer liquors in an alumina refinery includes a first step of reacting lime with aluminate ions in a Bayer liquor within a primary reactor operated at low to moderate temperature to form a hydrocalumite species and hydroxyl ions. In a second step, the hydrocalumite species is heated in contact with a Bayer liquor, which either includes or is a different liquor than the Bayer liquor of the first step, under controlled conditions to cause the hydrocalumite species to react with the liquor to form calcium carbonate, aluminate ions and hydroxyl ions. The principal advantages of the improved process include very high lime utilisation efficiencies (in excess of 90%) and a substantially increased C/S ratio (in excess of 0.955), allowing higher plant caustic concentrations and improved productivity. The loss of alumina due to the formation of unwanted calcium aluminate species is also greatly reduced.
    Type: Grant
    Filed: March 23, 2001
    Date of Patent: January 13, 2004
    Assignee: Worsley Alumina Pty LTD
    Inventors: Steven Philip Rosenberg, Darrel James Wilson, Catherine Ann Heath
  • Publication number: 20030202923
    Abstract: A reinforcing aluminum-based filler which can be used for reinforcing diene rubber compositions intended for the manufacture of tires, comprising an aluminum (oxide-)hydroxide corresponding, with the exception of any impurities and the water of hydration, to the general formula (a and b being real numbers):
    Type: Application
    Filed: April 30, 2003
    Publication date: October 30, 2003
    Applicant: Compagnie Generale des Etablissements, Michelin - Michelin & Cie.
    Inventors: Emmanuel Custodero, Laure Simonot, Jean-Claude Tardivat
  • 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: 6610261
    Abstract: A reinforcing aluminum-based filler which can be used for reinforcing diene rubber compositions intended for the manufacture of tires, comprising an aluminum (oxide-)hydroxide corresponding, with the exception of any impurities and the water of hydration, to the general formula (a and b being real numbers): Al(OH)aOb, with 0<a≦3 and b=(3-a)/2,  (I) the specific BET surface area of which is between 30 and 400 m2/g, the average particle size (by mass) dw of which is between 20 and 400 nm and the disagglomeration rate, &agr;, of which, measured via an ultrasound disagglomeration test at 100% power of a 600-watt ultrasonic probe, is greater than 5×10−3 &mgr;m−1/s is provided. A rubber composition suitable for the manufacture of tires comprising said aluminum-based filler as reinforcing filler.
    Type: Grant
    Filed: May 30, 2000
    Date of Patent: August 26, 2003
    Assignee: Compagnie Générale des Etablissements Michelin - Michelin & Cie
    Inventors: Emmanuel Custodero, Laure Simonot, Jean-Claude Tardivat
  • 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: 6485696
    Abstract: Ozone is used to rapidly oxidize specific metallic elements. The insoluble oxidized compounds of the metals formed by the ozonation are then recovered for industrial use in a conventional sedimentation/filtration tank or pool. There is no requirement for pre-treating or neutralizing the acid mine discharge, even when iron is the dominant metal. If the pH of the untreated acid mine discharge is less than about 2.5, metals other than iron precipitated first. After that, the pH is raised and the iron is precipitated as ferric hydroxide. Aluminum is removed as hydrated aluminum compounds after removal of the iron prior to discharging the acid mine discharge to streams. Both the ozonation and neutralization processes are monitored and controlled using electrochemical sensors and feedback controllers.
    Type: Grant
    Filed: October 29, 1999
    Date of Patent: November 26, 2002
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventors: Motoaki Sato, Eleanora I. Robbins
  • Publication number: 20010051121
    Abstract: A method for processing alumina-bearing ores such as bauxite to recover iron, aluminum, silicon and titanium metal values therefrom the method comprising the steps of adding the alumina-bearing ores to a digester containing an acid to provide a mixture of acid and alumina-bearing ores and heating the mixture to dissolve soluble compounds of at least one of iron, aluminum, silicon and titanium to provide a digest containing dissolved salts of the soluble compounds and to provide a gas component. Thereafter, the digest is treated with water to dissolve water soluble salts therein to provide a slurry comprised of a liquid containing water and the dissolved soluble salts and a solid component comprised of silica. The solid component is separated from the liquid and the pH of the liquid is adjusted to form an aluminate and an iron-containing precipitate.
    Type: Application
    Filed: May 3, 2001
    Publication date: December 13, 2001
    Inventors: Robert J. Barnett, Michael B. Mezner
  • Patent number: 6328938
    Abstract: A method for the integration of a manufacturing facility with a salt dome, which manufacturing facility is one for the production of high purity titanium dioxide using chlorine as a reactant. The metal chlorides produced as a by-product of titanium dioxide production are reacted with sodium hydroxide to produce metal hydroxide precipitates in an aqueous sodium chloride solution, which is then conducted into a reservoir of brine in a salt dome. The metal hydroxide precipitates are allowed to settle and the sodium chloride solution mixes with the brine. A portion of the brine is conducted to the surface where it is decomposed to produce chlorine, hydrogen, and sodium hydroxide. The chlorine and sodium hydroxide are recycled for use in the overall integrated process.
    Type: Grant
    Filed: May 23, 2000
    Date of Patent: December 11, 2001
    Inventors: Timothy L. Taylor, Tommy G. Taylor
  • Patent number: 6319483
    Abstract: It is possible to recover gallium and indium efficiently and at a low cost from solutions containing traces of gallium and indium. In particular, jarosite is produced by performing a specific treatment on a solution obtained by a two-stage neutralization treatment during the zinc leached residue treatment step of wet zinc refining, or on another solution containing traces of gallium and indium; the gallium and indium are separated and concentrated; an alkali is added to the jarosite; and the gallium is separated and concentrated by leaching. Calcium hydroxide or magnesium hydroxide is optionally added to the jarosite leached solution to perform purifying, sulfuric acid is added to the purified solution, neutralization is performed, basic gallium sulfate is precipitated, the precipitate is subjected to alkali leaching, and the gallium in the leached solution is electrolytically extracted, yielding metallic gallium.
    Type: Grant
    Filed: January 12, 2000
    Date of Patent: November 20, 2001
    Assignee: Dowa Mining Co., Ltd.
    Inventors: Yoshito Kudo, Yukiko Maruyama
  • Patent number: 6299846
    Abstract: The present invention provides a process for producing aluminum hydroxide with little contamination by silica at a high yield, while suppressing losses of consumed alumina and alkaline components. The process comprises the steps of mixing a first alumina-containing slurry with a preheated alkaline aqueous solution, extracting alumina from the mixture, separating a dissolution residue from the mixture to obtain a solution, mixing the solution with a second alumina-containing slurry, extracting alumina from the mixture, and precipitating aluminum hydroxide after a desilication treatment.
    Type: Grant
    Filed: November 15, 1999
    Date of Patent: October 9, 2001
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Takuo Harato, Toru Ogawa, Takahiro Ishida
  • Patent number: 6296819
    Abstract: A process for the manufacture of coarse aluminum hydroxide via the Bayer Process. The process involves the decomposition of a supersaturated alkaline aluminate liquor in a two stage precipitation process having an agglomeration stage and a growth stage. The agglomeration stage takes place in agglomeration tanks, where the liquor is seeded with fine aluminum hydroxide to induce precipitation and formation of a suspension, followed by a growth stage, where the suspension is seeded with a coarse aluminium hydroxide. Typically, the feed of the supersaturated alkaline aluminate liquor is split over a first agglomeration tank at a higher liquor temperature of 70° to 100° C. and a second agglomeration tank or one or more of a series of second agglomeration tanks at a lower liquor temperature of 50° to 80° C.
    Type: Grant
    Filed: October 20, 1999
    Date of Patent: October 2, 2001
    Assignee: Alusuisse Technology & Management Ltd.
    Inventors: Hans Jürg Schenk, Hans-Peter Breu, Arvind Bhasin
  • Patent number: 6296817
    Abstract: Disclosed is the recycling of aluminum dross. Aluminum dross is crushed into particles which are size-classified on the basis of 1 mm. The aluminum dross particles equal to or smaller than 1 mm in size are leached with an aqueous sodium hydroxide solution to give a leachate which contains sodium aluminate as a result of the reaction the aluminum metal of the aluminum dross particles with sodium hydroxide. The aluminum dross particles greater than 1 mm in size are remelted to recover aluminum metal. In the leachate, a small quantity of aluminum hydroxide is seeded, followed by hydrolyzing the sodium aluminate to obtain aluminum hydroxide. Meanwhile, the leachate is filtered to obtain a residue. This residue is subjected to washing, drying and roasting. The mixing of the roasted residue with aggregate and alumina cement gives alumina castable refractories.
    Type: Grant
    Filed: September 22, 1999
    Date of Patent: October 2, 2001
    Inventors: Hyung-Kyu Park, Hoo-In Lee, Eui-Pak Yoon
  • Patent number: 6296818
    Abstract: A process for treating an alumina monohydrate-based bauxite by high temperature caustic digestion includes the steps of introducing alumina trihydrate into the digested slurry at a temperature of less than 200° C., in order to obtain an aluminate liquor at atmospheric pressure having an alumina/caustic weight ratio between 1.20 and 1.30, and diluting the resultant aluminate liquor to result in a caustic concentration between 160 and 175 g Na2O/liter. After settling and filtration, the resulting supersaturated liquor undergoes a further dilution before or during a crystallization step. The alumina trihydrate product is filtered from the spent liquor, which is concentrated and recycled.
    Type: Grant
    Filed: June 16, 1999
    Date of Patent: October 2, 2001
    Assignee: Aluminium Pechiney
    Inventor: Jean-Michel Lamerant
  • Publication number: 20010012498
    Abstract: Process for treating alumina monohydrate-based bauxite by high-temperature caustic digestion characterized in the following series of operations:
    Type: Application
    Filed: June 16, 1999
    Publication date: August 9, 2001
    Inventor: JEAN-MICHEL LAMERANT
  • Patent number: 6231822
    Abstract: A method of recovering chloride and sulfate salts from spent potliner using acid digestion.
    Type: Grant
    Filed: November 30, 1998
    Date of Patent: May 15, 2001
    Assignee: Goldendale Aluminum Company
    Inventors: Robert J. Barnett, Michael B. Mezner
  • Patent number: 6221233
    Abstract: The smelting of aluminum from alumina in the Hall-Heroult process can be dramatically improved by lowering power consumption and in the use of carbon free anodes by using a feed of positively charged alumina. Laboratory experiments have shown that the apparent solubility and reactivity of alumina in molten fluoride baths is surprisingly increased by altering the negatively charged aluminum hydroxide Al(OH)4− particles, at about pH of nine, to positively charged particles containing Al+++ with a pH of less than two, by using acid solutions. The alumina thus produced is referred to as Al+++ alumina, or positively charged alumina. In particular, sulfuric acid is used to convert aluminum hydroxide using the Bayer process to a family of basic aluminum sulfates, 3Al2O3.4SO3.9H2O, which are dehydrated and calcined to produce Al+++ alumina.
    Type: Grant
    Filed: March 8, 1999
    Date of Patent: April 24, 2001
    Inventor: John S. Rendall
  • Patent number: 6217622
    Abstract: A method of forming and classifying a precipitate containing large, coarse and fine particles from a super-saturated precipitating mother slurry, e.g. sodium aluminate from the Bayer process. The method comprises separating the precipitating mother slurry into a plurality of separate streams, introducing each stream into a vessel provided with an agitated lower zone and a quiescent upper zone to form the precipitate, with the large and coarse particles remaining as a slurry in the agitated lower zone and the fine particles migrating to the quiescent zone, removing product slurry from the lower agitated zone, and removing spent liquor containing the fine particles from the quiescent upper zone. The invention also provides apparatus for carrying out the method. The combined precipitation and partial classification (separation of fine particles) makes it possible to deal with high solids charges increasingly encountered in industrial processes.
    Type: Grant
    Filed: October 22, 1998
    Date of Patent: April 17, 2001
    Assignee: Alcan International Limited
    Inventor: Bryan Hiscox
  • Patent number: 6168767
    Abstract: A process of recovering alumina from a pregnant Bayer process liquor by crystallisation after adding to the liquor a crystallisation modifier characterised in that the crystallisation modifier comprises: (a) a polyalkoxylated non-ionic surfactant, (b) a surfactant, or precursor thereof, which is not a polyalkoxylated non-ionic surfactant and (c) water. In a further aspect of the invention the composition may contain water but preferably contains substantially no water. Preferred compositions for the crystallisation modifier for use in this process contain a surfactant blend which consists essentially only of the polyalkoxylated non-ionic surfactant (a) and the surfactant (b) or precursor thereof. The process consistently gives excellent improvement in crystal size without decreased yield. Specifically the process results in a reduction in the percentage of undersized crystals.
    Type: Grant
    Filed: January 13, 1999
    Date of Patent: January 2, 2001
    Assignee: Ciba Specialty Chemicals Water Treatments Limited
    Inventors: Roger Welton, Philip McColl
  • Patent number: 6153157
    Abstract: A process which allows the conversion of clay minerals of the kalonite group, to a relatively pure form of alumina and silica respectively comprising the steps of (a) heating the kaolinite group minerals to greater than 500.degree. C., which causes dehydroxylation of the crystallographic lattice and formation of an intermediate meta-kaolin; (b) reacting the intermediate with only one of a selection of reagents including acids, alkalines or metalliferous compounds followed by heating of the mixture to form an aluminium salt in solution and residue of silica; (c) separation of the aluminium salt solution from the residue of silica by filtration and further treatment of the silica residue to produce a relatively pure form of fine particled silica; (d) formation of an alum by addition of ammonium sulphate in solution to the aluminium salt solution and further treatment of the alum to produce a relatively pure form of aluminium hydroxide.
    Type: Grant
    Filed: December 31, 1998
    Date of Patent: November 28, 2000
    Assignee: McLaughlin Geosurveys Pty. Limited
    Inventor: Robert Joseph McLaughlin
  • Patent number: 6123908
    Abstract: A process of treating spent potliner material from aluminum reduction cells and recovering useful products. In the process of the present invention, spent potliner material is introduced into an acid digester containing, for example, sulfuric acid. As a result of this step, a gas component is produced which includes hydrogen fluoride, silicon tetrafluoride and hydrogen cyanide. Also, a slurry component is produced which includes carbon, a refractory material including silica, alumina, sodium compounds such as sodium sulfate, aluminum compounds such as aluminum sulfate, iron compounds such as iron sulfate, magnesium and calcium compounds such as magnesium and calcium sulfate. The slurry component remains in the digester after the gas component is removed. The gas component is recovered and heated an effective amount to convert or decompose the silicon tetrafluoride to fumed silica, hydrogen cyanide to a remaining gas component including CO.sub.2, H.sub.2 O, and nitrogen oxides, as well as HF gas.
    Type: Grant
    Filed: March 27, 1999
    Date of Patent: September 26, 2000
    Assignee: Goldendale Aluminum Company
    Inventors: Robert J. Barnett, Michael B. Mezner
  • Patent number: 6110433
    Abstract: The invention relates to a process for recovering metals from used nickel/hydride storage batteries, in which storage battery scrap has been mechanically comminuted and divided into at least a coarse fraction and a fine fraction capable of being treated separately from one another. The process comprises the steps of digesting and dissolving the fine fraction with a mixture of sulfuric acid and hydrogen peroxide, performing a double sulfate precipitation of the rare earths by raising the pH, performing a precipitation of the iron and of the aluminum by further raising the pH, performing a solvent extraction of other metals to separate nickel and cobalt which remain in the aqueous phase from the other metals which are extracted into the organic phase. Optionally, the nickel and the cobalt can be separated from each other and, if desired, the mixed-metal rare earth component which has been recovered can be melted together with cobalt and nickel alloy for the fabrication of new batteries.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: August 29, 2000
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Klaus Kleinsorgen, Uwe Kohler, Alexander Bouvier, Andreas Folzer
  • Patent number: 6110434
    Abstract: A process for recovering one of alumina hydrate, magnesium hydroxide and magnesium aluminate spinel (MgAl.sub.2 O.sub.4) from aluminum dross wherein the dross is processed to a non-metallic product (NMP). The dross may contain fluxing salts which are removed in providing the NMP. The NMP may be derived from aluminum dross which does not contain fluxing salts sometimes referred to as white dross. The process comprises digesting the non-metallic product with an acid selected from the group consisting of sulfuric, hydrochloric, hydrofluoric and phosphoric acid or mixtures thereof to provide a slurry containing dissolved alumina, magnesia and a solid component, for example, containing magnesium aluminate spinel. Instead of an acid, a base such as sodium hydroxide may be used. The slurry is filtered to separate the solid component from the liquid containing dissolved constituents such as alumina and magnesia to recover the solid component.
    Type: Grant
    Filed: February 24, 1999
    Date of Patent: August 29, 2000
    Assignee: Alumitech of Cleveland, Inc.
    Inventors: John W. Pickens, Michael D. Waite
  • Patent number: 5980856
    Abstract: This invention relates to synthetic chalcoalumite-type compounds represented by formula (1) below:M.sup.2+.sub.a-x/2 Li.sub.x.sup.1+ Al.sub.4.sup.3+ (OH).sub.b (A.sup.n-).sub.c.mH.sub.2 O (1)(whereinM.sup.2+ represents at least one of the following divalent metal ions: Zn.sup.2+, Cu.sup.2+, Ni.sup.2+ and Mg.sup.2+,a is 0.6<a<1.2,x is 0<x<1.4,b is 11<b<13,A.sup.n- is at least one member of the group consisting of SO.sub.4.sup.2-, HPO.sub.4.sup.2-, CO.sub.3.sup.2-, SiO.sub.3.sup.2-, SO.sub.3.sup.2-, HPO.sub.3.sup.2-, H.sub.2 PO.sub.4.sup.-, NO.sub.3.sup.- and OH.sup.-,c is 0.5<c<1.2, andm represents a number of 1 to 4)and processes for their preparation. The synthetic chalcoalumite-type compounds of the present invention are conveniently used for adsorbing agents of acidic substances, anion exchangers, infrared absorption agents for agricultural films, deodorants and recording media for ink jet, etc.
    Type: Grant
    Filed: November 24, 1997
    Date of Patent: November 9, 1999
    Assignee: Kyowa Chemical Industry Co., Ltd.
    Inventors: Akira Okada, Kazushige Oda, Kanako Shimizu
  • Patent number: 5955042
    Abstract: A process for treating spent potliner material from aluminum reduction cells and recovering useful products. In the process, spent potliner material is introduced into an acid digester containing, for example, sulfuric acid. A gas component is produced which includes hydrogen fluoride and hydrogen cyanide. A slurry component is produced which includes carbon, silica, alumina, sodium compounds such as sodium sulfate, aluminum compounds such as aluminum sulfate, iron compounds such as iron sulfate, magnesium and calcium compounds such as magnesium and calcium sulfate. The slurry component remains in the digester after the gas component is removed. The gas component is recovered and heated an effective amount to convert or decompose the hydrogen cyanide to a remaining gas component including CO.sub.2, H.sub.2 O, and nitrogen oxides, as well as HF gas. The remaining gas component is directed through a water scrubber in which the HF gas is converted to liquid hydrofluoric acid.
    Type: Grant
    Filed: November 24, 1997
    Date of Patent: September 21, 1999
    Assignee: Goldendale Aluminum Company
    Inventors: Robert J. Barnett, Michael B. Mezner
  • 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: 5792236
    Abstract: Liquid gallium or gallium alloy is utilized as a mercury substitute for a variety of applications. The liquid gallium or gallium alloy is either free of metal oxides or has only very low quantities of metal oxides.
    Type: Grant
    Filed: November 20, 1995
    Date of Patent: August 11, 1998
    Assignee: Virginia Tech Intellectual Properties, Inc.
    Inventors: Larry T. Taylor, James Rancourt
  • Patent number: 5690700
    Abstract: A process for the precipitation of aluminum trihydroxide from a supersaturated sodium aluminate solution, comprising the steps of(a) supplying a stream of supersaturated sodium aluminate solution and a first stream of aluminum trihydroxide particles as seed particles to a first reaction circuit,(b) maintaining the sodium aluminate stream containing the stream of seed particles in the first reaction circuit under conditions mainly resulting in precipitation and agglomeration of aluminum trihydroxide,(c) passing the stream thus obtained to a second reaction circuit in which the stream is maintained under conditions mainly resulting in precipitation and growth of aluminum trihydroxide particles,(d) passing the stream obtained in the second reaction circuit to a separation/classification unit to separate the stream into a first aluminum trihydroxide product stream comprising the coarser particle size portion, a second aluminum trihydroxide product stream comprising the finer particle size portion and a spent liqu
    Type: Grant
    Filed: November 28, 1995
    Date of Patent: November 25, 1997
    Assignee: Billiton Intellectual Property B.V.
    Inventor: Iwan Dilip Kumar Hiralal
  • Patent number: 5605669
    Abstract: This invention relates to the preparation of cesium salts from cesium-aluminum-alum in a process in which the cesium-aluminum-alum is reacted in a single vessel in the presence of water with calcium hydroxide in an amount which is equimolar to the amount of aluminum and with a readily water-soluble calcium salt in an amount which is equimolar to the amount of cesium and the precipitated aluminum hydroxide and the precipitated calcium sulfate are separated by filtration or centrifugation.
    Type: Grant
    Filed: November 24, 1995
    Date of Patent: February 25, 1997
    Assignee: Metallgesellschaft Aktiengesellschaft
    Inventors: Hartmut Hofmann, Klaus K obele, Horst Prinz, Bernd Phillipp, Gerd Harms, Alexander Schiedt, Ulrike Hecktor
  • Patent number: 5558847
    Abstract: Aluminum and fluorine are recovered from fluorine containing waste materials from the production of aluminum metal (FCWM) as ALF.sub.2 OH hydrate by a process comprising: leaching FCWM with dilute sulphuric acid at a pH value within the range of 0-3; if needed adding aluminum in an acid soluble form; adjusting the pH value of the aqueous phase to a value within the range 3.7-4.1 at the end of the leaching period by addition of a caustic aqueous solution; precipitating silica at a temperature not exceeding 60.degree. C.; separating the reaction mixture into a solid phase containing precipitated silica and non-soluble residues of the FCWM and a purified solution; and precipitating AlF.sub.2 OH hydrate from the purified solution at a temperature within the range 90.degree.-100.degree. C. and at a pH value not exceeding about 4.1 by controlled continuous addition of an aqueous caustic solution. Reducing and/or non-oxidizing operating conditions are maintained during all these process steps. The precipitated AlF.
    Type: Grant
    Filed: May 5, 1995
    Date of Patent: September 24, 1996
    Inventors: Henning Kaaber, Mogens Mollgaard
  • Patent number: 5529761
    Abstract: A process is disclosed for the production of alumina by the Bayer process, including a precipitation process having an agglomeration stage and a growth stage in which the precipitation slurry is passed through a multiplicity of growth tanks. In the agglomeration stage, the precipitation slurry is maintained at a temperature of about 75.degree. C. to 85.degree. C. In the growth stage, the agglomeration slurry is cooled by about 1.degree. C. to 3.degree. C. in each growth tank of the multiplicity of growth tanks as compared to an adjacent previous growth tank. The temperature of the precipitation slurry leaving the final precipitator is preferably about 55.degree. C.
    Type: Grant
    Filed: October 4, 1994
    Date of Patent: June 25, 1996
    Assignee: Comalco Aluminum Limited
    Inventors: Gregory P. Brown, David G. Wood
  • Patent number: 5435986
    Abstract: An improved process for making high purity aluminum hydroxide [Al(OH).sub.3.3H.sub.2 O] of the hydrargillite form containing the steps of: (a) adding a non-powdered aluminum solid, preferably aluminum ingots, into a hot water bath at about 70.degree. C. to form a reaction mixture; (b) stirring the reaction mixture for about 20 minutes: (c) adding an alkaline-generating solid, preferably sodium hydroxide solids, into the reaction mixture and heating the reaction mixture to reach boiling point temperature; (d) lowering the temperature of the reaction mixture to 75.degree..about.80.degree. C. and stirring the reaction mixture for about 60 minutes; (e) lowering the temperature of the reaction mixture to room temperature; and (f) filtering the reaction mixture to obtain the high purity aluminum hydroxide form. The high purity of the final product was confirmed by data from X-ray diffraction and thermogravimetric analysis.
    Type: Grant
    Filed: August 30, 1994
    Date of Patent: July 25, 1995
    Assignee: Industrial Technology Research Institute
    Inventor: Cyril C. K. Chiang
  • Patent number: 5424351
    Abstract: An antistatic agent imparting excellent antistatic property to the polyacetal resins and the polyacetal resins using this antistatic agent. The antistatic agent for polyacetal resins is obtained by including polyalkylene polyols or metal salt-dissolved polyalkylene polyols in a basic carbonate of metals consisting chiefly of alkali metals and aluminum having a porous volume of 0.5 cc/g or larger over a region of meso pores to quasi-macro pores of porous radii of from 200 to 1000 angstroms or in an anion exchanger thereof, said porous volume being greater than 30% of the whole porous volume, and a polyacetal resin composition in which said antistatic agent is blended. The antistatic agent of the invention imparts stable antistatic properties to the above resins and is little dependent upon the environment, and further does not lose thermal property or mechanical strength that occurred with the conventional antistatic agents.
    Type: Grant
    Filed: March 18, 1994
    Date of Patent: June 13, 1995
    Assignees: Mizusawa Industrial Chemicals, Ltd., Polyplastics Corporation Ltd.
    Inventors: Yoshinobu Komatsu, Hiroshi Igarashi, Takahisa Erami
  • Patent number: 5419883
    Abstract: An lithium aluminum complex hydroxide salt (LAHS) and a process for preparation thereof is provided. The LAHS is represented by the formula;(Al.sub.2 Li(OH).sub.6).sub.n X, mH.sub.2 Owherein X is an inorganic or organic anion, n is a value number of X, and m is a number of not more than 3, and having an orientation degree (OD) of not less than 10, OD being defined by the formula;OD=I.sub.(002) /I.sub.(110)wherein I.sub.(002) is a relative intensity of a peak in X-ray diffraction pattern with an index of a plane (002) appearing at a spacing (d) of 7.67 .ANG. to 7.84 .ANG. and I.sub.(110) is a relative intensity of a peak in X-ray pattern with an index of a plane (110) appearing at a spacing (d) of 4.41 .ANG. to 4.45 .ANG.. This LAHS is useful for a stabilizer for chlorine-containing polymers or olefin-type resins containing halogen-containing catalyst residues.
    Type: Grant
    Filed: March 15, 1994
    Date of Patent: May 30, 1995
    Assignee: Mizusawa Industrial Chemicals, Ltd.
    Inventors: Masahide Ogawa, Kunio Goto, Shoji Shoji, Yoshinobu Komatsu, Akira Tatebe
  • Patent number: 5407650
    Abstract: A process for purifying an acidic technical-grade iron chloride solution formed from cyclone dust from the production of TiO.sub.2 in accordance with the chloride process by adjusting the pH with a first neutralizing agent and thereafter introducing the pH adjusted solution in a controlled manner into a solution containing a second neutralizing agent. In this process undesired ions which are to be separated, such as chromium, vanadium, zirconium and/or niobium, precipitate in the form of efficiently filterable hydroxides which can be separated industrially under economical conditions by filtration. The filter cake is non-hazardous and can safely be disposed of by dumping. Calcium carbonate is the preferred neutralizing agent, and the pH adjustment may also advantageously be effected by using scrap iron or by using iron sinters with reduction of any Fe(III) ions before the second neutralization step.
    Type: Grant
    Filed: December 21, 1993
    Date of Patent: April 18, 1995
    Assignee: Kronos, Inc.
    Inventors: Achim Hartmann, Ulrich Rothe, Dieter Schinkitz
  • Patent number: 5356567
    Abstract: A stabilizer for resin, which is composed of a lithium aluminum complex hydroxide salt represented by the following formulaAl.sub.2 Li(OH).sub.6).sub.n X.mH.sub.2 O . . . (1)wherein X is an inorganic or organic anion, n is a valence number of anion X, and m is a number of not more than 3.A chlorine-containing polymer composition comprising a chlorine-containing polymer and 0.01 to 10 parts by weight, per 100 parts by weight of the chlorine-containing polymer, of the above stabilizer. There is also provided an olefin-type resin composition comprising an olefin-type resin containing halogen-containing catalyst residues and 0.01 to 10 parts by weight, per 100 parts by weight of the olefin-type resin, of the above stabilizer. The stabilizer has excellent heat stabilizing action.
    Type: Grant
    Filed: December 22, 1992
    Date of Patent: October 18, 1994
    Assignee: Mizusawa Industrial Chemicals, Ltd.
    Inventors: Masahide Ogawa, Kunio Goto, Shoji Shoji, Yoshinobu Komatsu, Akira Tatebe
  • Patent number: 5336480
    Abstract: In a process utilizing steam, the method of producing at least a portion of said steam includes heating a solid substance so as to generate steam, followed by capturing the generated steam at a pressure greater than one atmosphere gage pressure for use in the process at a pressure greater than one atmosphere gage pressure. Suitable solid substances are aluminum hydrate or aluminum fluoride. New hydrated aluminum containing products and uses for those products are obtained by the use of the process.
    Type: Grant
    Filed: June 26, 1992
    Date of Patent: August 9, 1994
    Assignee: Aluminum Company of America
    Inventors: Chanakya Misra, Steven W. Sucech
  • Patent number: 5334362
    Abstract: In order to treat metal chlorides obtained in the form of dust collector solids in the production of titanium dioxide by the chloride process, the inert constituents, especially particulate coke, is separated then the metals are selectively precipitated and a maturing phase under oxidative conditions is provided for. The residue consisting of metal hydroxides is also not thixotropic in the absence of inerts. As a result, the material to be deposited has been cut in half.
    Type: Grant
    Filed: September 23, 1992
    Date of Patent: August 2, 1994
    Assignee: Kronos, Inc.
    Inventors: Dieter Schinkitz, Hans Thumm
  • Patent number: 5286391
    Abstract: A process for improving the flocculation of suspended solids in a Bayer process liquor in a primary settler stage. The method includes the step of adding to a primary settler feed from about 1 to about 100 parts per million of a composition including a non-inverted, water-continuous polymer, said polymer being hydrolyzable in a Bayer process liquor to an acid form, said acid form being an active red mud flocculant.
    Type: Grant
    Filed: February 4, 1993
    Date of Patent: February 15, 1994
    Assignee: Nalco Chemical Company
    Inventors: John T. Malito, Michael G. Strominger
  • Patent number: 5258168
    Abstract: Disclosed is a method for preparing high purity alunite. In the method, a material selected from the group consisting of sodium sulfate, sodium bisulfate, ammonium sulfate, ammonium bisulfate, potassium sulfate and potassium bisulfate is provided and reacted with a source of aluminum hydroxide in a liquid. The reaction is carried out under acidic conditions, and alunite is recovered after separating, washing and drying.
    Type: Grant
    Filed: July 19, 1989
    Date of Patent: November 2, 1993
    Assignee: Aluminum Company of America
    Inventor: Chanakya Misra
  • Patent number: 5256389
    Abstract: The present invention includes metal oxide foam particles and a method of making the same. A decomposable metal salt feed solution is injected into a hot atomizing gas. The mixture of hot atomizing gas and feed solution is maintained in the reactor until the feed solution converts to metal oxide foam particles. The metal oxide foam particles have a high specific surface area.
    Type: Grant
    Filed: May 22, 1991
    Date of Patent: October 26, 1993
    Assignee: Cabot Corporation
    Inventors: Merrill Jordan, deceased, Steven R. Reznek, Matthew Neville, Brian A. Soucy, Bruce E. Mackay
  • Patent number: 5245116
    Abstract: A process for the treatment of spent pot linings impregnated with alkali metal cyanide and fluoric products by grinding previously crushed pot linings in the presence of lime, suspending the ground pot linings in an aqueous medium in order to precipitate a flux in the form of CaF.sub.2 accompanied by the release of soda, followed by the heating of the suspension at a temperature T>140.degree. C. in the presence of clay to form, after fixing the free soda, insoluble synthetic silicate compounds of the feldspathoid or zeolite type and finally the separation by filtration of the resulting solid phase from the liquid phase, which liquid phase is recycled to form a new ground pot lining suspension.
    Type: Grant
    Filed: November 18, 1991
    Date of Patent: September 14, 1993
    Assignee: Aluminium Pechiney
    Inventors: Jean-Claude Bontron, Pierre-Bernard Personnet, Jean-Michel Lamerant
  • Patent number: 5171547
    Abstract: The present invention is directed to a method for treating a sludge containing substantial amounts of chromium, aluminum, calcium, iron, and phosphorous. The method comprises forming a slurry of the sludge; reacting the slurry with an acid to dissolve substantially all the aluminum and chromium and provide a solids residue comprising mostly calcium sulfate; separating the chromium/aluminum-containing solution from the solids residue; raising the pH of the chromium/aluminum solution to precipitate chromium as chromium hydroxide; and separating the chromium hydroxide from the remaining aluminum-containing solution. The chromium hydroxide is then enriched with an alkali or earth alkali compound and calcined in an oxidizing atmosphere to convert the chromium to a chromate. The calcine is leached in an aqueous medium at a controlled pH to yield a high concentration, high purity chromate solution suitable for producing metallic chromium or a variety of chromium chemicals.
    Type: Grant
    Filed: September 19, 1990
    Date of Patent: December 15, 1992
    Assignee: Amax, Inc.
    Inventors: Ranko Crnojevich, Andrew B. Case, Felix D. Rando, John D. Sweeney