Halogenating Patents (Class 423/163)
  • Patent number: 10583394
    Abstract: Embodiments of the present disclosure are directed to systems and methods of removing carbon dioxide from a gaseous stream using magnesium hydroxide and then regenerating the magnesium hydroxide. In some embodiments, the systems and methods can further comprise using the waste heat from one or more gas streams to provide some or all of the heat needed to drive the reactions. In some embodiments, magnesium chloride is primarily in the form of magnesium chloride dihydrate and is fed to a decomposition reactor to generate magnesium hydrochloride, which is in turn fed to a second decomposition reactor to generate magnesium hydroxide.
    Type: Grant
    Filed: February 23, 2016
    Date of Patent: March 10, 2020
    Assignee: CARBONFREE CHEMICALS HOLDINGS, LLC
    Inventors: Joe Jones, Al Yablonsky
  • Patent number: 9359221
    Abstract: The present invention relates to an energy efficient carbon dioxide sequestration processes whereby Group 2 silicate minerals and CO2 are converted into limestone and sand using a two-salt thermolytic process that allows for the cycling of heat and chemicals from one step to another.
    Type: Grant
    Filed: July 8, 2011
    Date of Patent: June 7, 2016
    Assignee: SKYONIC CORPORATION
    Inventors: Joe David Jones, Al Yablonsky
  • Patent number: 8858833
    Abstract: The invention is directed to a process of combining an aqueous solution of a fluoride with an aqueous solution of a host multi-valent metal salt and an aqueous solution of a salt forming a reactant mixture resulting in a precipitate of aqueously insoluble rare-earth doped multi-valent metal fluoride nanoparticles.
    Type: Grant
    Filed: May 31, 2006
    Date of Patent: October 14, 2014
    Assignee: E I du Pont de Nemours and Company
    Inventors: Changzai Chi, Daniel Albert Green, Kurt Richard Mikeska, Lee A. Silverman
  • Patent number: 8420034
    Abstract: In an exhaust gas treatment, the amount of a highly corrosive mercury-halogenating agent to be added is reduced with the mercury-removing efficiency maintained high. A mercury-halogenating agent (40) and ammonia (30) are added to combustion exhaust gas from a boiler, the exhaust gas containing NOx, SOx and mercury. The exhaust gas is brought into contact with a CO/HC oxidation catalyst (50) and is then subjected to reduction denitration (60) in the presence of a solid catalyst. Thereafter, metallic mercury is oxidized to halogenated mercury. Then, the exhaust gas is wet-desulfurized (100) with the alkaline absorbing solution, and the halogenated mercury is removed.
    Type: Grant
    Filed: February 26, 2009
    Date of Patent: April 16, 2013
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Katsumi Nochi, Yoshiaki Obayashi, Masashi Kiyosawa, Shintaro Honjo
  • Publication number: 20120168157
    Abstract: The present invention relates to a method for making pure salt comprises recapturing post-drilling flowback water from hydro-fracturing; removing oil from the flowback water; filtering the flowback water using an ultra filter with a pore size of about 0.1 microns or less to remove solid particulates and large organic molecules, such as benzene, ethylbenzene, toluene, and xylene, from the water; concentrating the flowback water to produce a brine that contains from about 15 wt % to about 40 wt % of salt relative to the total weight of the flowback brine; performing one or more chemical precipitation process using an effective amount of reagents to precipitate out the desired high quality commercial products, such as, barium sulfate, strontium carbonate, calcium carbonate; and crystallizing the chemically treated and concentrated flowback brine to produce greater than 99.5% pure salt products, such as sodium and calcium chloride.
    Type: Application
    Filed: March 15, 2012
    Publication date: July 5, 2012
    Applicant: FRACPURE HOLDINGS LLC
    Inventors: Frank A. DiTommaso, Peter N. DiTommaso
  • Publication number: 20120171091
    Abstract: The present invention relates to a method for making pure salt comprises recapturing post-drilling flowback water from hydro-fracturing; removing oil from the flowback water; filtering the flowback water using an ultra filter with a pore size of about 0.1 microns or less to remove solid particulates and large organic molecules, such as benzene, ethylbenzene, toluene, and xylene, from the water; concentrating the flowback water to produce a brine that contains from about 15 wt % to about 40 wt % of salt relative to the total weight of the flowback brine; performing one or more chemical precipitation process using an effective amount of reagents to precipitate out the desired high quality commercial products, such as, barium sulfate, strontium carbonate, calcium carbonate; and crystallizing the chemically treated and concentrated flowback brine to produce greater than 99.5% pure salt products, such as sodium and calcium chloride.
    Type: Application
    Filed: March 15, 2012
    Publication date: July 5, 2012
    Applicant: FRACPURE HOLDINGS LLC
    Inventors: Frank A. DiTommaso, Peter N. DiTommaso
  • 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: 6797249
    Abstract: The invention provides a process for the production of amorphous silica from a silica-based material having a silica content of at least 90% comprising: a) heating said silica-based material with CaCl2, at a temperature in the range of about 900° C. to about 1,200° C. and in the presence of water vapor in excess of the stoichiometric amount needed for the reaction: x CaCl2+y SiO2+x H2O→(CaO)x·(SiO2)y+2x HCl wherein x is equal to or greater than y to obtain a conversion of said silica-based material to calcium silicates in excess of 99.9%; b) Leaching said calcium silicates with HCl to form a solution of CaCl2 with insoluble silica; c) separating said insoluble silica from solution; and d) recycling the CaCl2 solution from step “c” to step “a”.
    Type: Grant
    Filed: August 1, 2002
    Date of Patent: September 28, 2004
    Assignee: Promeks AS
    Inventor: Joshua Samuel
  • Patent number: 6692710
    Abstract: The present invention provides methods for the isolation and production of magnesium products from leaching of laterite material with acid. A magnesium compound is formed by downstream treatment of a leach stream after at least one of nickel or cobalt have been brought into solution. Magnesite is then obtained by adding at least one of alkali metal or alkaline earth metal carbonate to the leach stream. The magnesite may be converted into magnesium chloride by adding an acid, such as HCL.
    Type: Grant
    Filed: March 22, 2001
    Date of Patent: February 17, 2004
    Assignee: Crew Development Corporation
    Inventor: Brian J. Ballou
  • Patent number: 6622523
    Abstract: The present invention provides a two stage process of thermal separation of CFCs and HCFCs followed by vitrification of the waste into a commercially viable glass. In the first stage, the hydrogenated compounds are reacted at elevated temperature with water and a metal oxide such as calcium oxide to form a halide salt and carbon dioxide. In the second stage of the process, the brine slag is reacted at elevated temperature with the carbon dioxide from stage one and glass-forming raw materials such as silicon dioxide to produce a glass. The final glass product incorporates the halide into the glass.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: September 23, 2003
    Inventors: Christopher J. Ludwig, Frederic M. Schwartz
  • Patent number: 6524546
    Abstract: A new process for producing calcium chloride and other metal halides from the carbonates, bicarbonates, oxides of these metals. The process utilizes the discovery that hydrogen halides, when used in a true or conventional fluidizing medium in shallow beds of the aforementioned solids at moderately elevated temperatures in a continuous counter current process results in the conversion of the metal carbonates, bicarbonates, and oxides, into metal halides and carbon dioxide gas and/or water vapor. The process is carried out in a series of true or conventional fluidized beds preferable but not necessarily arranged in a vertical configuration so that the solids flow downward due to the fluidized process and the hydrogen halides flow counter currently in an upward direction producing metal halides at the bottom and pure carbon dioxide gas and/or water vapor at the top.
    Type: Grant
    Filed: November 2, 2001
    Date of Patent: February 25, 2003
    Inventors: William J. Rigby, Keith D. Cochran, Timothy G. Holt
  • Patent number: 6497850
    Abstract: Methods and apparatus for the production of low sodium lithium carbonate and lithium chloride from a brine concentrated to about 6.0 wt % lithium are disclosed. Methods and apparatus for direct recovery of technical grade lithium chloride from the concentrated brine are also disclosed.
    Type: Grant
    Filed: November 7, 2000
    Date of Patent: December 24, 2002
    Assignee: Chemetall Foote Corporation
    Inventors: Daniel Alfred Boryta, Teresita Frianeza Kullberg, Anthony Michael Thurston
  • Patent number: 6425973
    Abstract: A method of treating solid containing material derived from effluent or sludge from a plant for de-inking paper, the material containing calcium in the form of one or more insoluble calcium compounds, the method including the steps of treating the material with an acid to cause dissolution of the calcium thereby forming a calcium ion-containing solution in which insoluble solids are suspended, separating the solution from the insoluble solids and incinerating the separated solids. The solution containing calcium ions may be treated by adding one or more reagents to form a calcium compound precipitate, eg calcium carbonate. The particulate solids produced following the incineration step and following the precipitate formation may be employed as pigments or fillers in paper making or paper coating.
    Type: Grant
    Filed: November 22, 2000
    Date of Patent: July 30, 2002
    Assignee: Imerys Minerals Limited
    Inventor: Jonathan Stuart Phipps
  • Patent number: 6193945
    Abstract: Method of recovering calcium carbonate from waste material or contained natural calcic material. Calcium is recovered by prepariag an aqueous suspension the material containing calcium to be recovered and by lowering the pH of the suspension to pH<6, preferably pH<4, for providing a spension including an acidic liquid phase containing the calcium compounds in soluble form. Thereafter the pH of the liquid is raised to pH>6, preferably pH>7, by mixing a base therein, for precipitating the main portion of aluminium therein. Thereafter the neutral or basic liquid phase is carbonized by introducing Na2CO3 or NaHCO3 therein, for precipitation of the calcium compounds as CaCO3.
    Type: Grant
    Filed: April 13, 1999
    Date of Patent: February 27, 2001
    Inventors: Markus Blomquist, Gunter Betz
  • 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: 6042794
    Abstract: A process for producing anhydrous magnesium chloride comprising steps of selective calcination of Mg-containing minerals, selective leaching of magnesium, separation of insoluble impurities, precipitation of magnesium chloride hexammoniate and thermal decomposition of the magnesium chloride hexammoniate crystals into magnesium chloride and ammonia.
    Type: Grant
    Filed: January 15, 1999
    Date of Patent: March 28, 2000
    Assignee: Norsk Hydro ASA
    Inventors: Ketil Amundsen, Hans Ragnar Eklund, Ralf Schmidt
  • Patent number: 6001316
    Abstract: Method of treatment of environmentally hazardous waste material and recovering MgCl.sub.2 brine, based on dissolving of the waste material in water and hydrochloric acid and simultaneous removal of ammonia at elevated temperatures, destruction of residual aqueous ammonia and removal of Mn, where the material is pre-treated in a special mixing unit adding water to provide a slurry and where hydrogen and other evolved gases are continuously diluted.
    Type: Grant
    Filed: December 18, 1997
    Date of Patent: December 14, 1999
    Assignee: Norsk Hydro ASA
    Inventors: Birger Langseth, Jean Beliveau, Bernard Perreault
  • Patent number: 5980854
    Abstract: The present invention is concerned with a method for the extraction of magnesium from magnesium-containing materials such as magnesite, dolomite and silicates materials like serpentine residues, products from the amphibole or pyroxene group. The magnesium-containing material is first leached in at least one leaching reactor, and subsequently submitted to a series of neutralizing steps in separate reactors under controlled pH and oxydo-reduction potentials. The slurry produced is filtered to produce a substantially pure magnesium chloride solution containing less than 1 ppm of each contaminant present therein.
    Type: Grant
    Filed: September 23, 1998
    Date of Patent: November 9, 1999
    Assignee: Noranda, Inc.
    Inventors: Carl White, Michel Berube
  • Patent number: 5939035
    Abstract: The present invention relates to a process for reducing and/or removing inorganic matter from a material containing inorganic matter which comprises the steps of:(i) (a) treating the material with a source of hydrogen fluoride so as to form a first residue and a first solution containing inorganic matter;(b) separating the first residue from the first solution containing the inorganic matter;(c) treating the first residue with an acid so as to form a second residue and a second solution containing further inorganic matter; and(d) separating the second residue from the second solution containing the further inorganic matter; or(ii) (a) treating the material with an acid so as to form a first residue and a first solution containing inorganic matter;(b) separating the first residue from the first solution containing the inorganic matter;(c) treating the first residue with a source of hydrogen fluoride so as to form a second residue and a second solution containing further inorganic matter; and(d) separating the
    Type: Grant
    Filed: June 4, 1997
    Date of Patent: August 17, 1999
    Assignee: The University of Melbourne
    Inventors: John Besida, Teresa Kit-Hing Pong, Robert Jacques Adrien, Geoffrey Harold Covey, Thomas Aloysius O'Donnell, David George Wood
  • Patent number: 5514359
    Abstract: In a process for producing anhydrous magnesium chloride, the following combination of steps: drying impure salt containing hydrated magnesium chloride; establishing a solution of the hydrated magnesium chloride; removing insoluble impurities; reacting the solution of hydrated magnesium chloride at substantially ambient temperature and pressure by feeding it into an ammonia saturated very low boiling point alcohol solution and in the presence of ammonium chloride while maintaining the last-mentioned solution saturated in ammonia thereby to form a precipitate of ammoniated magnesium chloride; separating the precipitate and heating it to obtain anhydrous MgCl.sub.2 and ammonia for recycling.
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: May 7, 1996
    Assignee: Alcan International Limited
    Inventors: Olivo G. Sivilotti, Jean V. Sang, Rejean J. R. Lemay
  • Patent number: 5362461
    Abstract: Calcium fluoride with high purity of very small content of unreacted calcium carbonate and silica is recovered from an etchant mainly composed of hydrogen fluoride or hydrogen fluoride and ammonium fluoride. The etchant is reacted with calcium carbonate with transfer directions of the etchant and calcium carbonate being controlled within a composition region in which mole equivalent ratio of ammonium fluoride/hydrogen fluoride is specified.
    Type: Grant
    Filed: October 1, 1992
    Date of Patent: November 8, 1994
    Assignee: Kurita Water Industries, Ltd.
    Inventors: Tadahiro Ohmi, Hiroyuki Harada, Nobuhiro Miki, Toshiro Fukutome, Matagoro Maeno, Norio Terasawa, Yoshihiro Eto, Masahiro Sakata
  • Patent number: 5350495
    Abstract: The invention relates to a method for separating sulphate from an aqueous electrolyte in an alkali metal chlorate process, thereby reducing the operating cost and increasing the possibility of further closing the electrolytical production of alkali metal chlorate. Calcium ions are added to a portion of the electrolyte, for precipitating calcium sulphate. By adjusting the pH within the range of from 4.6 up to about 7, and combining the temperature, content of ions and the molar ratio between sulphate and calcium ions added in a suitable manner, the calcium sulphate will precipitate predominantly as gypsum and essentially without inclusions and/or co-precipitation of chromium-containing compounds or chlorate. The precipitate is subsequently removed from the portion of electrolyte, whereafter the thus purified portion of electrolyte is recycled to the chlorate process.
    Type: Grant
    Filed: May 6, 1993
    Date of Patent: September 27, 1994
    Assignee: Eka Nobel AB
    Inventors: Stina Eriksson, Ulla-Kari Holmstrom
  • Patent number: 5348689
    Abstract: A process for destroying alkali metal and alkaline earth metal-containing wastes, such as sodium, by feeding such waste into a molten bath containing a molten salt such as sodium carbonate, or a mixture of salts having a lower melting point, such as a mixture of sodium carbonate and an alkali metal halide, e.g. sodium chloride, or mixtures of alkali metal chlorides, feeding a mixture of carbon dioxide and oxygen into the molten salt bath and reacting the alkali metal or alkaline earth metal such as sodium in the waste with the carbon dioxide and oxygen to form alkali metal carbonate, e.g. sodium carbonate, in the molten salt bath.
    Type: Grant
    Filed: July 13, 1993
    Date of Patent: September 20, 1994
    Assignee: Rockwell International Corporation
    Inventors: Ricahard L. Gay, Jerold Guon, John C. Newcomb
  • Patent number: 5227143
    Abstract: A process is disclosed for treating salt-containing aluminum dross to remove potassium and sodium chloride salts therefrom. The process generally comprises treating the dross in a first treating step with a leaching solution having a pH maintained in the range of about 6-7 to remove a portion of the salt content thereof; filtering the residual solids from the first leaching solution; and treating the filtered solids in a second treating step with a second leaching solution having a pH maintained above about 8, and preferably above about 9. The pH of the first leaching solution is maintained in the desired range by the addition of hydrochloric acid, and the pH of the second leaching solution is maintained in the desired range by the addition of potassium and/or sodium hydroxide.
    Type: Grant
    Filed: September 26, 1991
    Date of Patent: July 13, 1993
    Assignee: Aluminum Company of America
    Inventors: Donald L. Stewart, Jr., Jan H. L. vanLinden
  • Patent number: 5120514
    Abstract: Process for production of magnesium chloride with sufficient purity for the production of magnesium metal, by leaching a magnesium containing raw material in hydrochloric acid. It is essential to keep the ratio between acid soluble iron and nickel greater than 120 and the ratio between acid soluble iron and phosphorus greater than 20 in the primary magnesium chloride solution, to obtain a sufficiently pure product. The acid soluble iron can partly or completely be substituted by an equal, molar amount of acid soluble aluminium. It is especially preferred to use mixtures of macro- and crypto-crystalline magnesites in the ratio 1:10-10:1 as raw material.
    Type: Grant
    Filed: June 7, 1990
    Date of Patent: June 9, 1992
    Assignee: Norsk Hydro a.s.
    Inventors: Kjell W. Tveten, Glor T. Mejdell, Jan B. Marcussen
  • Patent number: 5112499
    Abstract: A two-stage process for treating acidic gypsum pond water for reuse or for discharge is disclosed. The first stage blends raw acidic pond water with recycled lime-treated slurry from the second stage of the process. The resulting elevation in pH causes CaF.sub.2 and SiO.sub.2 to precipitate and the precipitated material is discarded onto the gypsum storage area. The supernatant water can be used in the wet grinding mill and/or further treated in a second stage with lime to produce treated water which meets government environment standards for discharge. The slurry of calcium phosphate formed in the second (liming) stage is recycled to the first stage.
    Type: Grant
    Filed: May 22, 1991
    Date of Patent: May 12, 1992
    Assignee: Freeport-McMoran Resource Partners, Limited Partnership
    Inventors: Michael A. Murray, Charles W. Weston
  • Patent number: 5112584
    Abstract: Method for production of magnesium chloride, to be used for production of magnesium, by leaching of magnesite in hydrochloric acid. A two-stage leaching process is used where in a first reactor magnesite lumps are dissolved in hydrochloric acid. The magnesium chloride containing solution is led to a second reactor, where finely ground magnesite or hydrochloric acid is added to obtain approximate equivalence between magnesium and chlorine. To precipitate the impurities an excess of magnesium oxide or magnesium hydroxide is added in one or several purification stages.
    Type: Grant
    Filed: April 17, 1990
    Date of Patent: May 12, 1992
    Assignee: Norsk Hydro a.s.
    Inventors: Glor T. Mejdell, Hanne M. Baumann, Kjell W. Tveten
  • Patent number: 5106509
    Abstract: The invention relates to a process for the removal of fluoride from waste water in the form of a slightly soluble salt by mixing the waste water with a reagent. According to the invention the fluoride containing waste water is thoroughly mixed with the water soluble reagent at a suitable pH in a reactor of the fluidized bed type, which is provided with an appropriate seed material, on which the fluoride salt crystallizes out, whereby the thus obtained pellets comprising the seed material with the crystalline fluoride salt, is removed from and new seed material is added to the reactor from time to time. According to the present process as reagent CaCl.sub.2 is used, whereas the pH is adjusted to an appropriate value.
    Type: Grant
    Filed: January 22, 1991
    Date of Patent: April 21, 1992
    Assignee: DHV Raadgevend Ingenieursbureau B.V.
    Inventor: Cornelis W. Jansen
  • Patent number: 5102633
    Abstract: A method for reducing impurity levels of calcium, magnesium and/or silicon in hexammine cobalt halide compounds involves the addition of ferric ions and, optionally, soluble fluorides to an aqueous hexammine cobalt (III) chloride solution having a pH of at least 9. Insoluble compounds of magnesium fluoride, calcium fluoride, and/or ferric hydroxide and silicon coprecipitates are removed from the solution by filtration.
    Type: Grant
    Filed: May 20, 1991
    Date of Patent: April 7, 1992
    Assignee: GTE Products Corporation
    Inventors: Eric F. Husted, Michael J. Miller, Shellie K. Northrop, David T. Smith
  • Patent number: 5091161
    Abstract: A process for the production of pure magnesium chloride liquor from siliceous magnesium minerals comprises the steps of continuously leaching the siliceous magnesium mineral with a hydrochloric acid solution at a temperature higher than 50.degree. C. but below the boiling point and in such a manner as to maintain the pH of the slurry below 1.5 to prevent the formation of silica gel, continuously reacting such slurry with a reactive magnesia in order to raise the pH to 4.0-7.0 to precipitate substantially all the impurities from solution while preventing silica gel formation, and performing a solid/liquid separation of the slurry on suitable filtration equipment to obtain pure magnesium chloride liquor.
    Type: Grant
    Filed: August 20, 1990
    Date of Patent: February 25, 1992
    Assignee: Noranda, Inc.
    Inventors: G. Bryn Harris, John G. Peacey
  • Patent number: 5089094
    Abstract: In a process for the electrolytic production of magnesium by the molten salt electrolysis of magnesium chloride using a molten salt cell bath comprised mainly of one or more salts selected from alkali metal chlorides and alkaline earth metal chlorides, the molten salt bath is enriched with magnesium chloride by suspending a magnesium oxide and/or magnesium carbonate powder to form a molten suspension and passing a chlorine-containing gas through the molten suspension at a temperature of 600.degree.-900.degree. C. so as to react the suspended powder with chlorine to form magnesium chloride. The resulting molten salt enriched with magnesium chloride can be directly introduced into the cell for electrolysis, thereby eliminating moisture absorption by the highly hygroscopic magnesium chloride. A pure magnesium can be produced with a high yield and improved current efficiency.
    Type: Grant
    Filed: March 15, 1990
    Date of Patent: February 18, 1992
    Assignee: Osaka Titanium Company Limited
    Inventors: Tadashi Ogasawara, Yoshitake Natsume, Kenji Fujita
  • Patent number: 4937065
    Abstract: Halogenated hydrocarbons are reacted in a reactor at temperatures up to 1000.degree. C. with greater-than-stoichiometric amounts of calcium and/or magnesium silicates in a reactor for the chemical-thermal degradation of the halogenated hydrocarbons. Neither dioxins nor furans are formed in the waste gas in this process.
    Type: Grant
    Filed: December 6, 1988
    Date of Patent: June 26, 1990
    Assignee: Nukem GmbH
    Inventors: Paul-Gerhard Maurer, Daniel Neupert
  • Patent number: 4879101
    Abstract: A method for producing a magnesia powder for use as an electrical insulating material. A magnesia clinker powder is washed with an aqueous solution of an acid. The acid radical content of the powder is subsequently reduced to 0.015% by weight or less by washing the powder with water or by subjecting the powder to a heat treatment.
    Type: Grant
    Filed: February 29, 1988
    Date of Patent: November 7, 1989
    Assignee: Shin Nihon Chemical Industry Co., Ltd.
    Inventor: Yasuyoshi Oda
  • Patent number: 4838941
    Abstract: A reaction product of at least one of magnesium carbonate and magnesium silicate, with a metal chloride at a temperature exceeding 300.degree. C. Such a product, when mixed with water, sets to be an immensely strong magnesium cement. It may have aggregates of various types mixed with it.
    Type: Grant
    Filed: January 6, 1987
    Date of Patent: June 13, 1989
    Assignee: Ausmintec Corp. Limited
    Inventor: Robert G. D. Hill
  • Patent number: 4800003
    Abstract: A process for the production of Mg metal from impure Mg-containing materials is disclosed. The process comprises the steps of reacting a slurry of impure Mg-containing material with a hot HCl-containing gas stream to produce an impure MgCl.sub.2 slurry, purifying the MgCl.sub.2 slurry to form a substantially pure MgCl.sub.2 solution, drying the substantially pure MgCl.sub.2 solution to produce a MgCl.sub.2 powder containing up to about 5% each of MgO and H.sub.2 O, dehydration melting of the MgCl.sub.2 powder to produce molten anhydrous MgCl.sub.2, performing electrolysis of the molten anhydrous MgCl.sub.2 to produce Mg metal and Cl.sub.2, and recycling all of Cl.sub.2 produced during electrolysis to the above dehydration melting step for converting MgO and H.sub.2 O present in the MgCl.sub.2 powder into MgCl.sub.2 and HCl and for producing the hot HCl-containing gas stream. Dehydration melting is preferably done by feeding the MgCl.sub.2 powder into the feed end of a rotary kiln, and reacting Cl.sub.
    Type: Grant
    Filed: September 29, 1987
    Date of Patent: January 24, 1989
    Assignee: Noranda Inc.
    Inventors: John G. Peacey, G. Bryn Harris
  • Patent number: 4777030
    Abstract: A process is described for the recovery of silicon from a reaction mixture comprising silicon and an alkali metal fluoride.
    Type: Grant
    Filed: July 24, 1985
    Date of Patent: October 11, 1988
    Assignee: Enichem, S.p.A.
    Inventor: Kenneth M. Sancier
  • Patent number: 4743347
    Abstract: A process for producing a substantially pure, concentrated MgCl.sub.2 solution suitable for subsequent molten salt electrolysis to magnesium metal from an impure magnesite ore or concentrate is disclosed. The process comprises the steps of calcining a magnesite ore or concentrate at a temperature greater than 600.degree. C. to decompose most of the magnesite and form a reactive magnesia, dissolving such reactive magnesia with either concentrated hydrochloric acid or hydrogen chloride gas with the addition of a surface active wetting agent to produce an impure concentrated MgCl.sub.2 solution, and reacting such impure concentrated MgCl.sub.2 solution with a minimum of excess magnesia to increase the pH of the solution to at least 5.5 to precipitate undesirable impurities from solution and produce a substantially pure MgCl.sub.2 solution.
    Type: Grant
    Filed: May 11, 1987
    Date of Patent: May 10, 1988
    Assignee: Pamour Inc.
    Inventors: G. Bryn Harris, John G. Peacey, Serge Monette
  • Patent number: 4666688
    Abstract: Essentially pure strontium carbonate is recovered from low to medium grade strontium sulfate containing ores by first treating the ore with a hydrochloric acid solution to remove extraneous materials including calcium, magnesium, barium, and iron. The remaining strontium sulfate containing residue is treated with ammonium carbonate to produce insoluble strontium carbonate and soluble ammonium sulfate. The strontium carbonate then is converted to soluble strontium chloride through treatment with a second, stronger hydrochloric acid solution. Any remaining extraneous barium or iron is removed from the second acid solution before the strontium chloride is reconverted to insoluble strontium carbonate and precipitated out of solution for recovery.
    Type: Grant
    Filed: February 3, 1986
    Date of Patent: May 19, 1987
    Assignee: Excel-Mineral Company, Inc.
    Inventor: Francis de Buda
  • Patent number: 4610722
    Abstract: A process is provided for hydrometallurgical processing of steel plant dusts containing cadmium, lead, zinc, and iron values, along with impurities such as chloride and fluoride salts of sodium, potassium, magnesium, etc. The first step in the process involves leaching the dust in a mixed sulfate-chloride medium that dissolves most of the zinc and cadmium. Any iron and aluminum dissolved in this step is precipitated by oxidation and neutralization. Zinc is recovered from the resulting solution by solvent extraction which provides a raffinate which is recycled to the leaching step with a bleed stream also provided for recovery of cadmium and removal of other impurities from the circuit. The lead sulfate residue from the leaching step is leached with caustic soda, and zinc dust is used to cement the lead out from the caustic solution, which then joins the main solution for zinc recovery.
    Type: Grant
    Filed: January 31, 1985
    Date of Patent: September 9, 1986
    Assignee: AMAX Inc.
    Inventors: Willem P. C. Duyvesteyn, Robert F. Hogsett
  • Patent number: 4441993
    Abstract: A process for recovering metallic values by putting the values into solution and separating undesired mineral matter from the solution using countercurrent flotation is provided. The process involves leaching metallic values from host rock, conditioning the resultant ore pulp with the required reagents to achieve selective flotation of mineral matter in the metallic values solution, introducing the conditioned ore pulp into flotation cells, along with counterflow of solution from an immediately subsequent flotation step, wherein simultaneous washing and flotation is achieved, and the mineral matter is removed leaving a solution of the metallic values. The resultant mineral matter froth product is subjected to subsequent stages of flotation and simultaneous washing with counterflow of solution removed from each subsequent stage of flotation, water and/or barren solution being used for washing in the final flotation stage.
    Type: Grant
    Filed: May 3, 1979
    Date of Patent: April 10, 1984
    Assignee: Fluor Corporation
    Inventor: Frank P. Howald
  • Patent number: 4414185
    Abstract: A process for the preparation of calcium fluoride from industrial waste waters which comprises treatment of the waste waters with potassium hydroxide, followed by lime precipitation, neutralization with carbon dioxide and filtration to provide the calcium fluoride product.
    Type: Grant
    Filed: August 9, 1982
    Date of Patent: November 8, 1983
    Assignee: Chevron Research Company
    Inventor: Jonas P. Harrison
  • Patent number: 4374810
    Abstract: A process for obtaining calcium fluoride from the pond water of phosphoric acid plants and recycling the high phosphate defluorinated water to the pond is disclosed. Sufficient calcium carbonate is added to a solution having a pH of about 0.8, containing about 1% fluoride, 1% phosphate and less than 0.4% sulfate, to raise the pH thereof to 2-3, whereby calcium fluoride is precipitated as a major component, calcium phosphates and calcium sulfates are precipitated as minor components. The calcium fluoride precipitate obtained is washed with raw pond water to reduce the phosphate content and with ammonium carbonate solution to reduce the sulfate content. In this manner an industrially useful fluorspar is obtained. The low fluoride supernatant liquid is then mixed with sufficient raw pond water to bring the pH into the range 1.5-2.0 and the resulting suspension is then held in a lagoon for 5-21 days to permit separation of silica.
    Type: Grant
    Filed: June 4, 1979
    Date of Patent: February 22, 1983
    Assignee: Agrico Chemical Company
    Inventor: Padraic S. O'Neill
  • Patent number: 4341752
    Abstract: Method for producing purified and concentrated MgCl.sub.2 -brine by evaporation and crystallization from brines containing MgCl.sub.2, KCl, NaCl and MgSO.sub.4 involving recirculation of carnallite and part of the final product brine. The carnallite is recirculated to a decomposition step (1) into which the whole or part of the crude brine is also introduced while part of the final product brine is recycled to the evaporation step (2). The method results in a pure end product by a simple process comprising only one evaporation step and without any addition of chemicals.
    Type: Grant
    Filed: March 13, 1981
    Date of Patent: July 27, 1982
    Assignee: Norsk Hydro a.s.
    Inventor: Hendrik C. Groenhof
  • Patent number: 4320012
    Abstract: Method for neutralizing waste cooling pond waters of wet process phosphoric acid plants, and for neutralizing similar waste waters from phosphate complexes, wherein neutralization is performed in two stages and wherein the flocculent precipitate from the second neutralization stage is disposed of by dissolving it in incoming untreated waste water prior to the first neutralization stage. Neutralization in the first neutralization stage is accomplished by addition of limestone to the waste water, and neutralization in the second neutralization stage is accomplished by addition of limestone to the water phase from the first neutralization stage. The precipitate from the first neutralization stage is readily separable from the liquid phase, and is suitable for disposal in the gypsum stack of a wet process phosphoric acid plant. The fully neutralized water meets federal and state requirements for disposal in surface and underground water systems as to pH and as to fluoride and phosphate content.
    Type: Grant
    Filed: August 7, 1980
    Date of Patent: March 16, 1982
    Inventors: Gordon F. Palm, R. George Hartig
  • Patent number: 4289736
    Abstract: The addition of an excess of asbestos tailings in the course of the extraction of magnesium from asbestos tailings by digestion with an acid greatly facilitates the elimination of silica and other impurities by filtration of the resulting reaction mixture. The improvement reduces the filtration time and the filtration leaves a cake which is much easier to dispose.
    Type: Grant
    Filed: August 31, 1979
    Date of Patent: September 15, 1981
    Assignee: Universite de Sherbrooke
    Inventor: Jean M. Lalancette
  • Patent number: 4243643
    Abstract: Metal ion impurities are removed from phosphoric acid by adding to the acid a precipitant comprising ions of calcium and fluorine to cause precipitation of a magnesium-containing precipitate. A preferred precipitant is one containing calcium flouride, such as the sludge obtained by treating pond water from a phosphoric acid plant with a calcium-containing compound. Preferably, the soluble sulfate content of the phosphoric acid is maintained at at least about 2% by weight. An animal feed can be prepared from the precipitate by combining the precipitate with phosphate rock, water, and a sodium-containing compound, and then calcining the combination.
    Type: Grant
    Filed: October 25, 1978
    Date of Patent: January 6, 1981
    Assignee: Occidental Chemical Company
    Inventor: Harold E. Mills
  • Patent number: 4226710
    Abstract: A process for purifying water containing fluoride which comprises precipitating fluoride from the water as fluorapatite in the presence of a bed of seeding composition. Fluoride is removed as fluorapatite by having sufficient available calcium for each mole of fluoride present in the water and sufficient available phosphate for each mole of fluoride in the water to form a precipitate which is or converts to sufficient fluorapatite to remove essentially all fluoride from the water.
    Type: Grant
    Filed: February 12, 1979
    Date of Patent: October 7, 1980
    Assignee: Andco Industries, Inc.
    Inventor: Stanley Bruckenstein
  • Patent number: 4201750
    Abstract: A process for the preparation of magnesium compounds from breunnerite or from mineral concentrates or tailings containing breunnerite in which the mineral is calcined and treated with an acid and the magnesium salt solution so formed is separated from insoluble matter.
    Type: Grant
    Filed: April 24, 1978
    Date of Patent: May 6, 1980
    Assignee: Engelhard Minerals & Chemicals Corporation
    Inventor: Frank Pitts
  • Patent number: 4200618
    Abstract: An improved method of preparing magnesium chloride in which magnesium oxide, hydroxide or carbonate or a material containing magnesium oxide is caused to react with waste chlorides produced in the manufacture of titanium tetrachloride and the solution of magnesium chloride so formed is separated from insoluble matter.
    Type: Grant
    Filed: February 28, 1979
    Date of Patent: April 29, 1980
    Assignee: Engelhard Minerals & Chemicals Corporation
    Inventor: Frank Pitts
  • Patent number: 4195070
    Abstract: A method of beneficiating a mixed salt mineral ore containing potassium and magnesium sulfates and/or their hydrates which allows the recovery of anhydrous magnesium chloride and the simultaneous recovery of commercially acceptable potassium sulfate.
    Type: Grant
    Filed: March 21, 1979
    Date of Patent: March 25, 1980
    Assignee: Nalco Chemical Company
    Inventors: Ronald J. Allain, David G. Braithwaite, Joseph P. Maniscalco