Hydroxylating Or Hydrating Patents (Class 423/164)
  • Patent number: 9963351
    Abstract: A method for activation of magnesium silicate minerals by conversion to magnesium hydroxide for sequestration of carbon dioxide (CO2) is provided. The method includes heating a dry solid-solid mixture of an alkaline earth Silicate-based material with an alkali metal compound at a temperature below 300 C to form a solid product predominantly comprising a mixture of magnesium hydroxide and alkali metal silicate, wherein the Silicate-based material comprises a naturally occurring Olivine, Serpentine mineral and alkali metal silicate. The method includes a subsequent dissolution of the solid product in aqueous solution to form an alkaline aqueous liquid slurry, comprising solid and aqueous phase products and the reaction of the solid phase thus formed with Carbon Dioxide (CO2), producing a metal Carbonate. The method provides a process that has shown significant cost and energy efficiencies for producing magnesium hydroxide and CO2 sequestration via mineral carbonation.
    Type: Grant
    Filed: April 10, 2015
    Date of Patent: May 8, 2018
    Inventor: Michael Priestnall
  • Patent number: 9895649
    Abstract: A high solids magnesium hydroxide slurry may be provided. The slurry may include a magnesium hydroxide compound and a carbohydrate-based viscosity control agent. The slurry may further include sea water as at least a portion of the liquid component. The high solids magnesium hydroxide slurry may be utilized in connection with exhaust scrubber systems for removing SOx and NOx compounds from exhaust gas emissions.
    Type: Grant
    Filed: April 8, 2015
    Date of Patent: February 20, 2018
    Assignee: Premier Magnesia, LLC
    Inventors: Joe Christopher Brown, Jerry Elliott Rademan, Peyton L. Pool, Sr., Mark Alexander Shand, James O. Williams
  • Patent number: 9034100
    Abstract: The invention relates to CO2 capturing binder with an amortized environmental cost, the method of manufacture thereof by means of selecting, purifying and optimizing the carbide lime paste for use as a cementing material, and aggregates for the manufacture of lime paints and slurries, stuccos, mortars and concretes having multiple applications in the construction industry, in architectural restoration, in public works and land conditioning, object of the present invention. It is basically characterized in that the raw material is the residue in the form of sludge generated in the industrial manufacture of acetylene (C2H2) from calcium carbide (CaC2) the fundamental component of which is calcium hydroxide (Ca(OH)2) in highly reactive nanometric formations treated in a specific manner according to the invention.
    Type: Grant
    Filed: May 4, 2010
    Date of Patent: May 19, 2015
    Assignee: GEOSILEX TRENZA METAL, S.L.
    Inventors: Miguel Angel Bermejo Sotillo, Carlos Rodriguez Navarro, Encarnación Ruiz Agudo, Kerstin Elert
  • Patent number: 8900545
    Abstract: This invention refers to a novel process for obtaining high purity magnesium hydroxide from a solid starting material containing magnesium in the form of, and/or combined with, carbonates, oxides and/or hydroxides, either natural or synthetic. The process comprises leaching the starting material to dissolve the magnesium; the solution is treated with alkali to precipitate the high purity magnesium hydroxide, and the remaining mother liquor is fed to a regeneration step of both the alkali used in the precipitation of high purity magnesium hydroxide, and the acid for leaching. The process of the invention is characterized by recycling reactants (acid and alkali) regenerated in the same process.
    Type: Grant
    Filed: September 5, 2008
    Date of Patent: December 2, 2014
    Assignee: Servicios Administrativos Penoles S.A. de C.V.
    Inventors: Jesús Manuel Martinez Martinez, Herlindo Ortiz Ortega, Ricardo Benavides Pérez, José Gertrudis Bocanegra Rojas
  • Patent number: 8795614
    Abstract: The present invention relates to a method of economical extraction of magnesium, boron and calcium, while minimizing the loss of lithium, from a lithium bearing solution. More specifically, the present invention provides a method for economical extraction of magnesium, boron, and calcium, while minimizing the loss of lithium, from a lithium bearing solution comprising the steps of: (a) adding an alkali in the lithium bearing solution to precipitate magnesium hydroxide; (b) absorbing boron ions on the surface of the magnesium hydroxide by adjusting the pH to about 8.5 to about 10.5; and (c) simultaneously extracting magnesium and boron by filtering the magnesium hydroxide absorbed with the boron ions from the lithium bearing solution.
    Type: Grant
    Filed: January 8, 2013
    Date of Patent: August 5, 2014
    Assignee: Research Institute of Industrial Science & Technology
    Inventors: Uong Chon, Gi Chun Han, Ki Hong Kim, Chang Ho Song, Ki Young Kim
  • Patent number: 8778289
    Abstract: The present invention relates to a method of extracting lithium from a lithium bearing solution. More specifically, the present invention provides a method of economical extraction of lithium from a lithium bearing solution by adding a phosphorous supplying material to the solution to precipitate lithium phosphate from the dissolved lithium.
    Type: Grant
    Filed: January 8, 2013
    Date of Patent: July 15, 2014
    Assignee: Research Institute of Industrial Science & Technology
    Inventors: Uong Chon, Oh Joon Kwon, Ki Hong Kim, Chang Ho Song, Gi Chun Han, Ki Young Kim
  • Publication number: 20140186241
    Abstract: The present invention relates to a process for the production of a precipitated divalent metal ion carbonate product from a divalent metalion carbonate which was recovered from waste, the precipitated divalent metal ion carbonate product having an improved brightness, the process comprising the steps of: providing a low-purity divalent metal ion carbonate material, the divalent metal ion carbonate material being recovered from waste; calcining the divalent metal ion carbonate material in order to obtain a divalent metal ion oxide; slaking the divalent metal ion oxide in order to obtain an aqueous suspension of a divalent metal ion hydroxide; carbonating the aqueous suspension of the divalent metal ion hydroxide with a carbon dioxide containing compound in order to obtain fine precipitated divalent metal ion carbonate particles; posttreating the fine precipitated divalent metal ion carbonate particles to obtain fine discrete precipitated divalent metal ion carbonate particles; adding the fine discrete precipit
    Type: Application
    Filed: May 8, 2012
    Publication date: July 3, 2014
    Inventors: Michael Pohl, Thomas Schmölzer
  • Patent number: 8703093
    Abstract: A method is described for batchwise slaking of burnt lime in a slaker, in which a lime slurry is produced with a greater degree of fineness and prolonged sedimentation time, comprising the following processing steps: emptying of finished slaked and diluted lime slurry from the slaker; automatic coupling of a control system for automatic operation after the wanted slaking temperature has been reached in the first batch; automatic regulation of the slaking temperature in the subsequent slurry batch; and automatic registering of the remaining amount of slurry in the slaker after complete dosing of lime.
    Type: Grant
    Filed: March 12, 2012
    Date of Patent: April 22, 2014
    Inventor: Poju R. Stephansen
  • Patent number: 8691169
    Abstract: It is possible to produce battery grade metallic lithium from naturally occurring or industrial brine by a process comprising the following steps: (i) precipitating magnesium with calcium hydroxide; (ii) removal of boron via extraction of solvents; (iii) precipitation of lithium with sodium carbonate; (iv) transformation of lithium carbonate to bicarbonate of lithium with carbonic acid; (v) decomposition of bicarbonate of lithium into high purity lithium carbonate as a result of heating of the solution. Re-precipitation of lithium carbonate by the formation of bicarbonate of lithium allows for the removal of the majority of contaminants which co-purify with lithium carbonate and yield battery grade highly purified lithium carbonate.
    Type: Grant
    Filed: September 26, 2012
    Date of Patent: April 8, 2014
    Inventors: Waldo Perez, Hugo Adan Carlos Barrientos, Claudio Suarez, Marcelo Bravo
  • Patent number: 8679428
    Abstract: The present disclosure provides a method of preparing highly pure lithium carbonate from brine. The method includes adding an adsorbent to the brine, from which the magnesium ions Mg2+ have been removed, to adsorb lithium ions Li+ to the adsorbent, followed by providing the adsorbent having the lithium ions Li+ adsorbed thereto to a strong acid solution to desorb the lithium ions Li+ from the adsorbent; enriching the strong acid solution in which the lithium ions Li+ are desorbed from the adsorbent; and obtaining lithium carbonate Li2CO3 through chemical reaction between the lithium ions Li+ in the enriched solution and a carbonate precursor.
    Type: Grant
    Filed: October 12, 2011
    Date of Patent: March 25, 2014
    Assignee: Korea Institute of Geosciences and Mineral Resources (KIGAM)
    Inventors: Joon-Soo Kim, Kyeong-Woo Chung, Jin-Young Lee, Sung-Don Kim
  • Patent number: 8658122
    Abstract: This invention refers to a novel process to obtain magnesium hydroxide and sodium sulfate from a solid raw material, which contains sodium and magnesium soluble salts, preferably in the form of sulfates, coming from a natural source or as a byproduct of an industrial process. The process consisting in the conditioning of the raw material to guarantee the correct concentrations of sodium and magnesium sulfates that is subjected to a salting-out crystallization when mixed with sodium sulfate obtaining sodium sulfate; the resulting solution is subjected to an alkali treatment to precipitate the magnesium hydroxide and the mother liquor is fed to a regeneration stage of the alkali used in the precipitation of the magnesium hydroxide as well in the sodium sulfate solution for the crystallization. The crystallization can be performed as a multistage process countercurrent to increase the purity of sodium sulfate.
    Type: Grant
    Filed: December 14, 2007
    Date of Patent: February 25, 2014
    Assignee: Servicios Administrativas Penoles S.A. de C.V.
    Inventors: Jesús Manuel Martinez Martinez, Armando Garcia López, José Gertrudis Bocanegra Rojas, Ricardo Benavides Pérez
  • Publication number: 20140030173
    Abstract: A process for the continuous modification of dihydrate gypsum includes calcining dihydrate gypsum into hemihydrate gypsum and recrystallizing the hemihydrate gypsum in an aqueous slurry to convert the hemihydrate gypsum into modified dihydrate gypsum of different crystalline form. The aqueous slurry in a recrystallization reaction tank is maintained at a constant temperature under stirring, and a feed rate of the hemihydrate gypsum to the recrystallization reaction tank and a discharge rate of the recrystallized dihydrate gypsum are controlled to substantially equal. Dihydrate gypsum as a starting raw material can be converted into high-purity, modified dihydrate gypsum of large crystals by recrystallizing the starting dihydrate gypsum after it is once calcined into hemihydrate gypsum.
    Type: Application
    Filed: August 8, 2013
    Publication date: January 30, 2014
    Inventors: Itaru YOKOYAMA, Kouji KATSUMOTO, Yasuo KAWAMURA
  • Publication number: 20130343972
    Abstract: A method for treating liquid effluents and recovering metals is described, which comprises the steps of: a) liquid effluent equalization; b) sulphide addition and precipitation of metals in the form of metal sulphides; c) solid/liquid separation of the metal sulphides produced in step (b) and formation of a metal-free liquid phase; d) addition of a 50 to 250 g/L amine solution to the liquid phase precipitating magnesium in the form of magnesium hydroxide (Mg(OH)2); and e) recovery of amine by stripping and rectification.
    Type: Application
    Filed: August 9, 2011
    Publication date: December 26, 2013
    Applicant: VALE S.A.
    Inventors: Salomão Solino Evelin, Roberto Mattioli Silva, Geraldo Luiz Da Silva, Clauson De Souza
  • Patent number: 8388915
    Abstract: A method for producing basic magnesium sulfate granules, by heating a water-containing granular composition to a temperature of 50-250° C. to dryness. The granular composition has a water content of 10-60 wt. % and comprises fibrous basic magnesium sulfate particles, magnesium hydroxide in an amount of 5-300 weight parts per 100 weight parts of the fibrous basic magnesium sulfate particles, magnesium sulfate in an amount of 0.1-200 weight parts per 100 weight parts of a total amount of the fibrous basic magnesium sulfate particles and magnesium hydroxide. This method can give basic magnesium sulfate granules having a low bulk density and a high crushing strength.
    Type: Grant
    Filed: March 30, 2009
    Date of Patent: March 5, 2013
    Assignee: Ube Material Industries, Ltd.
    Inventors: Shinichi Yamamoto, Takashi Kishimoto
  • Publication number: 20120328497
    Abstract: A method of producing calcium carbonate from a waste sludge containing calcium carbonate and at least one silicate mineral. The method comprises the steps of: (i) incinerating the sludge to an ash in which at least 60% of the calcium carbonate present in the sludge is converted to free calcium oxide which is unreacted with the silicate mineral(s), (ii) optionally slaking the ash to convert at least a portion of the free calcium oxide therein to calcium hydroxide, (iii) treating either the ash from step (i) or the slaked ash from step (ii) with an aqueous solution of a polyhydroxy compound to provide a solution of dissolved calcium hydroxide, (iv) separating insoluble material from the solution of calcium ions obtained in step (iii), (v) dispersing carbon dioxide through the solution obtained from step (iv) so as to produce calcium carbonate, and (vi) separating the calcium carbonate produced in step (v).
    Type: Application
    Filed: June 14, 2012
    Publication date: December 27, 2012
    Inventor: Robert Philip Higgs
  • Patent number: 8158098
    Abstract: Provided herein are processes for obtaining sylvinite and/or sylvite from sea water, sea bitterns and/or sea salts. The processes comprise reacting sea water, sea bitterns and/or sea salts with calcium hydroxide and/or calcium oxide.
    Type: Grant
    Filed: June 22, 2010
    Date of Patent: April 17, 2012
    Assignee: Exportadora de Sal, S.A. de C.V.
    Inventor: Abraham Sadan
  • Patent number: 8153088
    Abstract: A method to prevent build-up of limestone in a slaker that is used for batchwise slaking of burnt lime is described, in which lime slurry is produced with a greater degree of fineness and prolonged sedimentation time, where for immediate cleansing of the slaker before next slaking, after said calibration of the load cell aggregate, a number of valves are opened for given time periods for addition of flushing water to respective nozzles, in that flushing water is supplied sequentially via each valve to associated nozzle(s), until a predetermined amount of flushing water is reached in the slaker.
    Type: Grant
    Filed: February 15, 2008
    Date of Patent: April 10, 2012
    Assignee: Poju R. Stephansen AS
    Inventor: Poju R. Stephansen
  • Patent number: 8128897
    Abstract: A continuous process for purification of brine contaminated with alkaline earth metals. The process comprises combining the brine with an aqueous solution containing at least one of an alkali metal hydroxide and an alkali metal carbonate with efficient mixing by a micro-mixing device.
    Type: Grant
    Filed: May 6, 2008
    Date of Patent: March 6, 2012
    Assignee: Morton Salt, Inc.
    Inventors: Roma Gimelfarb, Kurt John Waatti, Francis Joseph Lipiecki, Stephen Gerard Maroldo, Kenneth Eugene Sloffer
  • Patent number: 8067494
    Abstract: Magnesium oxide (MgO) compounded into a polymer can subsequently be hydrated in-situ within the polymer to form magnesium hydroxide. In the case of silane-based or peroxide-based crosslinkable resins, the MgO hydration and polymer crosslinking can be done in a single process step, or in sequential steps. In the case of non-crosslinkable compounds, hydration can be carried out after compounding (no crosslinking step). In all cases, steam CV, sauna, or hot water bath are options for hydration. This approach enables preparation of polymer compounds that are flame retarded with metal hydrates yet free of the traditional limitations posed by shelf instability, extrusion scorch, undesired dehydration, and processing temperature limitations posed by metal hydrates.
    Type: Grant
    Filed: October 29, 2007
    Date of Patent: November 29, 2011
    Assignee: Dow Global Technologies LLC
    Inventors: Jeffrey M. Cogen, Ashish Batra, Geoffrey D. Brown, Paul D. Whaley
  • Patent number: 8016913
    Abstract: An improved method for processing of nickel-bearing ores, laterite ores, saprolite and limonite ores, oxidic and sulfide ores, metallurgical wastes, and other metal-bearing materials, to recover the valuable minerals contained therein, comprising comminuting ore to a desired size; leaching the ore at about 70 C to 130 C for about 30 minutes to 4 hours with nitric acid, raising the temperature of the solution to form a liquid/solid residue in which nickel, cobalt and magnesium values are in solution, and iron, manganese, and aluminum are solid residues in oxide form; conducting a liquid-solid separation and removing the solids; and recovering the nickel, cobalt, and manganese from the liquid-metal concentrate. The leachate is recovered and the nitric acid from the leachate is recycled.
    Type: Grant
    Filed: May 1, 2008
    Date of Patent: September 13, 2011
    Assignee: Drinkard Metalox, Inc.
    Inventor: William F. Drinkard, Jr.
  • Patent number: 7914756
    Abstract: A method of treating alkaline industrial by-products, such as red mud generated by Bayer process bauxite refining, is described. Embodiments of the method comprise treating the alkaline industrial by-products with salts of divalent and/or polyvalent cations, thereby lowering pH of the alkaline industrial by-products. The method involves replacement reactions in which relatively insoluble hydroxide salts form precipitates, thereby removing hydroxide ions from solution.
    Type: Grant
    Filed: November 10, 2003
    Date of Patent: March 29, 2011
    Inventors: Philip N. Baldwin, Jr., Norman K. Murray, Charles Richard Lee, Michael W. Farrall
  • Patent number: 7887769
    Abstract: A method of removing sulfur dioxide from flue gases using calcium and magnesium scrubbing components and treatment of oxidized effluent from such a system includes passing classified oxidized effluent to a regeneration tank and adding lime to produce a regenerator discharge containing magnesium hydroxide, gypsum and crystalline inert material. Gypsum is separated from the discharge and a magnesium hydroxide stream passed to a concentration system to produce a concentrated solids stream of magnesium hydroxide, residual minor amount of gypsum and crystalline inert material. A portion of the resultant stream is returned to the sulfur dioxide removal system while a portion is passed to the oxidizer. Further portions may be fed to a power plant boiler or to the flue gas stream between a solids collection device and the wet scrubber.
    Type: Grant
    Filed: December 1, 2009
    Date of Patent: February 15, 2011
    Assignee: Carmeuse Lime, Inc.
    Inventor: Kevin J. Smith
  • Patent number: 7871584
    Abstract: A process for the recovery of nickel and cobalt from nickel and cobalt containing ores, including the steps of first leaching a laterite ore and/or a partially oxidized sulfide ore with an acid solution to produce a pregnant leach solution containing at least dissolved nickel, cobalt and ferric ions, and subsequently leaching a sulfide ore or concentrate with the pregnant leach solution to produce a product liquor. Alternatively, the laterite ore and/or partially oxidized sulfide ore can be leached in a combined leach with the sulfide ore or concentrate. The ferric ion content in the pregnant leach solution or in the combined leach is sufficient to maintain the oxidation and reduction potential in the sulfide leach high enough to assist in leaching nickel from the sulfide ore or concentrate.
    Type: Grant
    Filed: May 8, 2007
    Date of Patent: January 18, 2011
    Assignee: BHP Billiton SSM Technology Pty. Ltd.
    Inventors: Houyuan Liu, Alexey Duarte, Wolf Meihack
  • Patent number: 7595037
    Abstract: Described is a method as well as an apparatus for hydration of a particulate or pulverulent material containing CaO. The method is peculiar in that water is added in a quantity which will ensure that the partial pressure PH2O of the added water as a function of the temperature (° C.) is maintained within the interval defined by the formula (I), where PH2O is the partial pressure of water vapour in atm. and T is the temperature in ° C. Hereby is obtained that the material particles do not lump into agglomerates, and that the particles are hydrated evenly from the outside and inwards so that it is the active surface of the material particles which undergoes hydration in connection with partial hydration. This is due to the fact that the liquid water will not get into contact with the material particles since the water will appear in vapour form within the specified interval.
    Type: Grant
    Filed: February 16, 2005
    Date of Patent: September 29, 2009
    Assignee: FLSMIDTH A/S
    Inventors: Jens Peter Hansen, Lars Skaarup Jensen
  • Patent number: 7553462
    Abstract: A method for the production of Mg(OH)2 nanoparticles, by means of polyol-mediated synthesis, from an Mg precursor as well as a base. The particles produced with this method have a diameter between 10 nm to 300 nm, have a mono-disperse particle distribution, and are present in non-agglomerated form. They can be converted to MgO particles by means of calcination.
    Type: Grant
    Filed: June 18, 2007
    Date of Patent: June 30, 2009
    Assignee: K&S Aktiengesellschaft
    Inventors: Claus Feldmann, Sascha Ahlert, Jörg-Heino Sachse, Ingo Stahl
  • Publication number: 20090148365
    Abstract: A process for recovering solid magnesium sulfate hydrate from a source of magnesium sulfate in solution includes the steps of providing a source of magnesium sulfate in solution that is derived from part of a process associated with the leaching of a metal containing ore or concentrate; adding sulfuric acid to the magnesium sulfate solution to salt out the magnesium sulfate as magnesium sulfate hydrate crystals in a salting process, and partially diluting the sulfuric acid; recycling the diluted sulfuric acid for use in the process of leaching the metal containing ore or concentrate; and recovering the solid magnesium sulfate crystals.
    Type: Application
    Filed: June 19, 2008
    Publication date: June 11, 2009
    Inventors: Eric Girvan Roche, Jacqueline Whitehead
  • Publication number: 20090010827
    Abstract: A process for sequestration of carbon dioxide comprising the following steps: (a) dispersing solid waste material comprising calcium oxide and a calcium-comprising mixed oxide in water to dissolve at least part of the calcium oxide and to form calcium oxide-depleted solid waste material in a calcium hydroxide solution; (b) separating the calcium hydroxide solution from the calcium oxide-depleted solid waste material; (c) converting the calcium hydroxide in the separated calcium hydroxide solution in precipitated calcium carbonate; and (d) contacting an aqueous slurry of the calcium oxide-depleted solid waste material with carbon dioxide for mineral carbonation of the carbon dioxide to form carbonated solid waste material.
    Type: Application
    Filed: December 18, 2006
    Publication date: January 8, 2009
    Inventors: Jacobus Johannes Cornelis Geerlings, Gerardus Antonius Van Mossel, Bernardus Cornelis Maria In' T Veen
  • Patent number: 7282188
    Abstract: The invention concerns a method and an apparatus for producing a metal hydroxide, in particular magnesium hydroxide, from a salt solution, wherein the metal is firstly precipitated from the salt solution and the suspension produced in that way is then filtered. The object of the invention is to provide a method and an apparatus which permit simple inexpensive and rapid production of metal hydroxide, in particular magnesium hydroxide, in a high state of purity. According to the invention that is achieved in that the suspension is filtered through at least one filter (13-17) of a cross-flow filtration installation (13-17), and that a permeate produced by filtration of the suspension is fed to the cross-flow filtration installation (14-17) again.
    Type: Grant
    Filed: March 19, 2003
    Date of Patent: October 16, 2007
    Assignee: IMB + Frings Watersystems GmbH
    Inventors: Johannes Lindemann, Karl Manderscheld, Manfred Schneider
  • Patent number: 7179438
    Abstract: The present invention provides methods and apparatus for treating flue gas containing sulfur dioxide using a scrubber, and more particularly relates to recovering gypsum and magnesium hydroxide products from the scrubber blowdown. The gypsum and magnesium hydroxide products are created using two separate precipitation reactions. Gypsum is crystallized when magnesium sulfate reacts with calcium chloride. Magnesium hydroxide is precipitated when magnesium chloride from the gypsum crystallization process reacts with calcium hydroxide. The process produces a high quality gypsum with a controllable pH and particle size distribution, as well as high quality magnesium hydroxide.
    Type: Grant
    Filed: January 3, 2006
    Date of Patent: February 20, 2007
    Assignee: Allegheny Energy, Inc.
    Inventor: Dennis K. Jones
  • 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: 20030026749
    Abstract: Disclosed is a process for reducing the amount of silicon in brine. More specifically the silicon content of the brine is reduced to 1 ppm or less by using low caustic excess. The disclosed process can also be characterized as lowering sodium hydroxide excess (caustic excess) while maintaining the sodium carbonate level thereby obtaining a brine with a low level of silicon. A further purification step employs a sludge blanket.
    Type: Application
    Filed: June 25, 2001
    Publication date: February 6, 2003
    Applicant: VULCANS CHEMICALS
    Inventors: Derrek R. Burrows, Brian W. Johnson
  • Patent number: 6428760
    Abstract: The present invention relates to the improvement of a replenishment method of a magnesium-based compound and to the improvement of a double decomposition method, which can be used in a magnesium hydroxide desulfurization method. In the improved replenishment method, the magnesium-based compound is supplemented with water and the ratio of Mg/H2O is adjusted to the total Mg/H2O in the desulfurization system. In the improved double decomposition method, a tank for use is provided with an inner cylinder which partitions the tank into an inner part and an outer part, but does not reach the bottom of the tank, and a part of the slurry drawn through the bottom of the tank is fed to the outer upper position in the tank.
    Type: Grant
    Filed: June 20, 2000
    Date of Patent: August 6, 2002
    Assignee: Toyo Engineering Corporation
    Inventors: Hideyuki Michiki, Hisashi Miyakawa, Mitsuo Okada, Tetsu Shimatani, Fumio Hori
  • Patent number: 6403045
    Abstract: A method for treating residues derived from garbage and/or industrial waste incineration fumes including the steps of desalting the residues by washing with sodium carbonate in sufficient amount or slightly in excess to solubilize all the salts including the sulphates and precipitate the soluble calcium, the pH being higher than 11, then carrying out a solid/liquid separation to obtain a desalinated cake; leaching the desalinated cake with sodium carbonate in sufficient amount or slightly in excess to obtain, by reaction with the lime present in the cake or added thereto if necessary, the alkalinity required for solubilising amphoteric metals, the pH being higher than 12, and obtaining by solid/liquid separation a cake and a supernatant which is neutralised with carbon dioxide, and filtering the recovered solution to obtain metal hydroxide sludge and an aqueous sodium carbonate solution; and neutralising the resulting residues at a pH between 6.5 and 8.5.
    Type: Grant
    Filed: March 14, 2000
    Date of Patent: June 11, 2002
    Assignee: FIBAC
    Inventors: Daniel Daviller, Laurent Rizet
  • 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: 6270631
    Abstract: A process for hydrating CaO residues in fluidized bed combustor ashes that achieves a better level of hydration, which does not add significantly to the cost of the hydration process, which reduces the consumption of water in the hydration process, and which if desired can trap at least some of the CO2 in the furnace gasses, by using some of it to convert the hydrated CaO to CaCO3. This both reduces the amount of CO2 released to the atmosphere, and converts the potentially dangerous CaO in the ashes into an effectively inert and benign material. By exposing the ash/water mixture to sound under the correct conditions of frequency, and power input, it is possible to improve both the rate of hydration, and the level of hydration, of FBC ashes. The process can be carried out either batchwise or continuously, and does not require an extended time period.
    Type: Grant
    Filed: August 9, 2000
    Date of Patent: August 7, 2001
    Assignee: Her Majesty the Queen in right of Canada, as represented by the Minister of Natural Resources
    Inventor: Edward J. Anthony
  • Patent number: 6267789
    Abstract: Process for enriching crude salt, in which the crude salt is ground and then cooled in a saturated aqueous sodium chloride solution, to a temperature below the anhydrous sodium chloride to sodium chloride dihydrate transition temperature, a stock of a powder comprising sodium chloride crystals is collected from the cooling step and the powder is subjected to particle-size fractionation from which a fine particle-size fraction and a coarse particle-size fraction comprising the enriched salt are collected.
    Type: Grant
    Filed: October 12, 1999
    Date of Patent: July 31, 2001
    Assignee: Solvay (Société Anonyme)
    Inventor: Léon Ninane
  • 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: 6143260
    Abstract: A method for producing lithium carbonate by precipitating magnesium as the hydroxide from a brine concentrated to a lithium concentration of about 6%. Lithium is then precipitated from the brine by addition of recycled limed mother liquor from a previous lithium precipitation step.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: November 7, 2000
    Assignee: Chemetall Foote Corporation
    Inventor: Daniel A. Boryta
  • 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: 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: 5891320
    Abstract: A clear solution and a method for preparing the solution which has a pH in the range of from 10 to 13.9 and containing sulfate ions in a concentration range less than 500 parts per million. The solution is prepared by mixing two solutions in which one solution has one equivalent of magnesium sulfate and an equivalent of sulfuric acid and the second solution has an equivalent of Ca (OH).sub.2 and two equivalents of K.sub.2 OH. It is believed that CaSO.sub.4 precipitates in the mixed solution and causes coprecipitation of potassium, perhaps as double salt with the Ca leaving OH stabilized by hydration and magnesium ions.
    Type: Grant
    Filed: August 26, 1996
    Date of Patent: April 6, 1999
    Inventors: Stephen R. Wurzburger, James M. Overton
  • Patent number: 5851500
    Abstract: Magnesium fluoride slag contaminated with metallic uranium or uranium compounds is treated by digestion with potassium hydroxide to soluble potassium fluoride and insoluble magnesium hydroxide. The solid and liquid phases are then separated and the solids phase is dissolved in acid to form a solution of metal salts. The liquid phase is treated with lime to precipitate calcium fluoride and convert the potassium back to potassium hydroxide for recycle to the digestion reaction. The metal salts are separated to remove the uranium salt from the magnesium salt. The result is an efficient removal of uranium contamination from the magnesium, the recovery of magnesium in a manner that permits efficient reuse or safe disposal, and the production of calcium fluoride useful for a variety of purposes.
    Type: Grant
    Filed: August 22, 1997
    Date of Patent: December 22, 1998
    Assignee: United States Enrichment Corporation
    Inventor: John H. Pashley
  • Patent number: 5738758
    Abstract: The disclosure relates to a process for the removal of solid CaS from a gas stream in which the CaS has been formed and then the conversion of that solid CaS by reaction with an aqueous NaOH solution to produce solid Ca(OH).sub.2 and a liquor stream containing dissolved NaHS. This removal and conversion process is described as being used in conjunction with a process for gasifying black liquor from a kraft pulping process in which H.sub.2 S is scrubbed from the gases using calcium compounds to form the CaS.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: April 14, 1998
    Assignee: The University of New Brunswick
    Inventor: Adriaan R. P. van Heiningen
  • Patent number: 5409680
    Abstract: A process for removing alkaline earth metal impurities (e.g. calcium and magnesium ions) from an aqueous alkali metal chlorate solution which includes adding sufficient alkali metal carbonate or hydroxide or both to the impure solution to raise the pH to above 9 and form alkaline earth metal precipitates which are then removed from the pH-adjusted solution (e.g. by microfiltration). This process can lower the level of these impurities from about 1-20 ppm to less than about 0.3 ppm or less.
    Type: Grant
    Filed: March 18, 1994
    Date of Patent: April 25, 1995
    Assignee: Olin Corporation
    Inventors: Jerry J. Kaczur, David W. Cawlfield, Julian F. Watson
  • 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: 5332564
    Abstract: A process for producing rhombic or barrel shaped precipitated calcium carbonate. Quicklime is slaked in an aqueous solution containing about 0.1% to about 2% by weight of a sugar, based upon the weight of the CaCO.sub.3 to be produced. Carbon dioxide is added to the slaked lime slurry at a preferred temperature of about 50.degree. F.-70.degree. F. until the pH drops from about 11-12 to about 7-8.
    Type: Grant
    Filed: July 10, 1992
    Date of Patent: July 26, 1994
    Assignee: ECC International Inc.
    Inventors: Vasant D. Chapnerkar, Mohan N. Badgujar
  • Patent number: 5286285
    Abstract: A finely powdery magnesium hydroxide especially suitable as a flame-retardant filler for plastic compounds, in which the particles are provided optionally with a thin coating of a surfactant. The grain size of the magnesium hydroxide, measured by laser diffraction, is below 10 .mu.m. The median value of the grain size is greater than 0.8 .mu.m, and the maximum of the median value of the grain size is 3 .mu.m. The contents of water-soluble ionic impurities, viz. Ca.sup.++, Na.sup.+, K.sup.+, SO.sub.4 --, Cl.sup.-, of the magnesium hydroxide are below the following limits (in parts by weight): Ca.sup.++ <1000 ppm, Na.sup.+ <20 ppm, K.sup.+ <20 ppm, SO.sub.4 --<1500 ppm, Cl.sup.- <1000 ppm. The contents of Mn, Cu and Ni are below the following limits (in parts by weight): MnO<100 ppm, NiO<100 ppm, CuO<10 ppm.
    Type: Grant
    Filed: June 4, 1993
    Date of Patent: February 15, 1994
    Assignee: Veitscher Magnesitwerke-Actien-Gesellschaft
    Inventors: Andreas Meier, Michael Grill