Sulfating Patents (Class 423/199)
  • Patent number: 10850230
    Abstract: Processes and systems for producing potassium sulfate as a byproduct of a desulfurization process. Sulfur dioxide is absorbed from a flue gas using an ammonia-containing solution to produce an ammonium sulfate solution that contains dissolved ammonium sulfate. At least a first portion of the ammonium sulfate solution is heated before dissolving potassium chloride therein to form a slurry that contains potassium sulfate crystals and an ammonium chloride solution. The slurry is then cooled to precipitate additional potassium sulfate crystals, after which the potassium sulfate crystals are removed to yield a residual ammonium chloride solution that contains dissolved ammonium chloride and residual dissolved potassium sulfate. Ammonia is then absorbed into the residual ammonium chloride solution to further precipitate potassium sulfate crystals, which are removed to yield a residual ammonium chloride solution that is substantially free of dissolved potassium sulfate.
    Type: Grant
    Filed: July 30, 2018
    Date of Patent: December 1, 2020
    Assignee: Marsulex Environmental Technologies Corporation
    Inventor: Eli Gal
  • Publication number: 20140334995
    Abstract: Methods of processing an aqueous solution comprising potassium sulfate and magnesium sulfate include crystallizing K2SO4, crystallizing recycle crystals, and mixing at least a portion of the recycle crystals with the aqueous solution. Systems for processing potassium sulfate and magnesium sulfate include a first crystallizer and a second crystallizer in fluid communication with the second mix tank. The second crystallizer is structured and adapted to precipitate recycle crystals from the concentrated liquor to form a potassium-depleted recycle brine. The recycle crystals precipitated in the second crystallizer have a composition suitable to be recycled to the first crystallizer to increase the production of SOP.
    Type: Application
    Filed: July 25, 2014
    Publication date: November 13, 2014
    Inventors: Steven L. CHASTAIN, Michael J. MORRISON, Richard W. CHASTAIN, Donial M. FELTON, Thomas H. NEUMAN
  • Patent number: 8877690
    Abstract: A method of treating a wastewater is provided and can be used, for example, to treat a gas well production wastewater to form a wastewater brine. The method can involve crystallizing sodium chloride by evaporation of the wastewater brine with concurrent production of a liquor comprising calcium chloride solution. Bromine and lithium can also be recovered from the liquor in accordance with the teachings of the present invention. Various metal sulfates, such as barium sulfate, can be removed from the wastewater in the production of the wastewater brine. Sources of wastewater can include gas well production wastewater and hydrofracture flowback wastewater.
    Type: Grant
    Filed: August 31, 2011
    Date of Patent: November 4, 2014
    Assignee: ProChemTech International, Inc.
    Inventor: Timothy Edward Keister
  • Patent number: 8753591
    Abstract: Molybdic oxide is recovered from molybdenite by a multistep process in which (A) the molybdenite is converted to soluble and insoluble molybdic oxide by pressure oxidation, (B) the insoluble molybdic oxide is converted to soluble molybdic oxide by alkaline digestion and then combined with the soluble molybdic oxide, and (C) the molybdenum values of the combined streams are extracted into an organic phase using a nonprimary amine. The extracted molybdenum values are recovered from the organic phase using aqueous ammonia to form ammonium dimolybdate (ADM) which is recovered as refined crystals from a two-step calcination process.
    Type: Grant
    Filed: February 28, 2013
    Date of Patent: June 17, 2014
    Assignee: Kennecott Utah Copper LLC
    Inventors: Mike Rockandel, Claus Stoiber, Robert E. Crossman
  • Patent number: 8721999
    Abstract: Kainite mixed salt is treated with water to obtain solid schoenite and a schoenite end liquor. The latter is desulphated using recycled CaCl2 and thereafter evaporated to obtain camallite crystals, from which KCl is recovered, and a liquor rich in MgCl2. Gypsum produced during desulphatation is reacted with aqueous ammonia and CO2 to produce ammonium sulphate and calcium carbonate. The calcium carbonate is calcined to obtained CaO and CO2. The CaO is slaked and reacted with the MgCl2-rich liquor generated above to produce slurry of Mg(OH)2 in aqueous CaCl2. To this surface modifying agent is added while hot and, after cooling, the slurry yields surface modified Mg(OH)2. The filtrate rich in CaCl2 is recycled for desulphatation process above. The solid surface modified Mg(OH)2 may he calcined to produced MgO. The schoenite and KCl are reacted to produce solid sulphate of potash.
    Type: Grant
    Filed: March 29, 2010
    Date of Patent: May 13, 2014
    Assignee: Council of Scientific and Industrial Research
    Inventors: Pushpito Kumar Ghosh, Haresh Mahipatlal Mody, Jatin Rameshchandra Chunawala, Maheshkumar Ramniklal Gandhi, Hari Chand Bajaj, Pratyush Maiti, Himanshu Labhshanker Joshi, Hasina Hajibhai Deraiya, Upendra Padmakant Saraiya
  • Patent number: 8551429
    Abstract: Methods of forming potassium sulfate include calcining polyhalite ore particles to convert the polyhalite ore particles to a water-soluble composition. At least a portion of the water-soluble composition is dissolved in an aqueous medium to form an aqueous solution comprising K+, Mg2+, and SO42? ions and a calcium-containing solid. The calcium-containing solid is separated from the aqueous solution to form a filtrate comprising K+, Mg2+, and SO42? ions. A potassium-containing salt is dissolved in the filtrate to increase the concentration of K+ and SO42? ions to from a concentrated liquor, and K2SO4 is crystallized from the concentrated liquor. A system for processing polyhalite ore includes a countercurrent leaching apparatus, a first mix tank, an evaporator, and at least one crystallizer.
    Type: Grant
    Filed: November 6, 2012
    Date of Patent: October 8, 2013
    Assignee: Intercontinental Potash Corp. (USA)
    Inventors: Thomas H. Neuman, Richard W. Chastain, Donial M. Felton, Daniel C. Neuman, Otto C. Schnauber
  • Publication number: 20130121900
    Abstract: Methods of forming potassium sulfate include calcining polyhalite ore particles to convert the polyhalite ore particles to a water-soluble composition. At least a portion of the water-soluble composition is dissolved in an aqueous medium to form an aqueous solution comprising K+, Mg2+, and SO42? ions and a calcium-containing solid. The calcium-containing solid is separated from the aqueous solution to form a filtrate comprising K+, Mg2+, and SO42? ions. A potassium-containing salt is dissolved in the filtrate to increase the concentration of K+ and SO42? ions to from a concentrated liquor, and K2SO4 is crystallized from the concentrated liquor. A system for processing polyhalite ore includes a countercurrent leaching apparatus, a first mix tank, an evaporator, and at least one crystallizer.
    Type: Application
    Filed: November 6, 2012
    Publication date: May 16, 2013
    Applicant: INTERCONTINENTAL POTASH CORP. (USA)
    Inventor: Intercontinental Potash Corp. (USA)
  • Publication number: 20130048562
    Abstract: A method of treating a wastewater is provided and can be used, for example, to treat a gas well production wastewater to form a wastewater brine. The method can involve crystallizing sodium chloride by evaporation of the wastewater brine with concurrent production of a liquor comprising calcium chloride solution. Bromine and lithium can also be recovered from the liquor in accordance with the teachings of the present invention. Various metal sulfates, such as barium sulfate, can be removed from the wastewater in the production of the wastewater brine. Sources of wastewater can include gas well production wastewater and hydrofracture flowback wastewater.
    Type: Application
    Filed: August 31, 2011
    Publication date: February 28, 2013
    Applicant: PROCHEMTECH INTERNATIONAL, INC.
    Inventor: Timothy Edward KEISTER
  • Publication number: 20120205253
    Abstract: Process for the combined regeneration of at least two soluble salts contained in a residue of an industrial process comprising heavy metals, comprising: adding an amount of reactive aqueous solution needed to completely dissolve the salts which are desired to be regenerated to the residue; subjecting the resulting aqueous suspension to a separation to obtain an aqueous production solution on the one hand and insoluble impurities on the other hand, which are removed; successively subjected the aqueous production solution to at least two selective crystallization steps intended to crystallize, separately, the at least two soluble salts which are desired to be regenerated, which are washed, dried and regenerated separately; and adjusting the concentration of at least one of the soluble salts to be regenerated in the aqueous production solution, at the moment when such solution is subjected to the step of crystallization of this salt, to give rise to the selective crystallization of this salt, by addition of a co
    Type: Application
    Filed: October 20, 2010
    Publication date: August 16, 2012
    Applicant: SOLVAY SA
    Inventors: Jean-Marie Blondel, Pierluigi Cassaghi, Cedric Humblot
  • Patent number: 8043596
    Abstract: The invention provides a method for producing carbon nanotubes, comprising spraying an oil onto a catalyst metal supported by at least one support selected from the group consisting of silica gel, alumina, magnesia, silica-alumina and zeolite which is placed in an atmosphere that has been controlled to a specific temperature, and an apparatus therefor. According to the invention, a large amount of carbon nanotubes can be synthesized from inexpensive raw materials by using a simple apparatus.
    Type: Grant
    Filed: September 21, 2005
    Date of Patent: October 25, 2011
    Assignee: Showa Denko K.K.
    Inventors: Tetsuo Soga, Maheshwar Sharon, Rakesh Ashok Afre
  • Patent number: 7514051
    Abstract: A method for purifying heavy metal impurities (such as antimony, arsenic, iron, cadmium, and lead) from 28 to 38 weight percent aqueous crude sodium sulfate solution is achieved by adding ferric sulfate to the aqueous crude sodium sulfate solution to form a suspension, progressively neutralizing the suspension from a pH of less than 3.5 up to at least 6, and separating the ferric-sulfate-nucleated precipitate from the suspension. An oxidizing agent such as peroxide is optionally added to the suspension to augment adsorption of the heavy metals.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: April 7, 2009
    Assignee: The Doe Run Resources Corporation
    Inventor: Matthew Pratt
  • Patent number: 7323150
    Abstract: A method for recovering at least one metallic element from ore or other material is described and includes reacting ore or other material with a salt capable of recovering the metallic element from the ore or other material to form a reaction product that includes the metallic element. The method also includes recovering the metallic element from the reaction product. To remove the metallic element from the reaction product, the method can involve crushing the reaction product to form a crushed material and dissolving the crushed material in a solvent to remove the precipitates, thereby leaving a sulfate solution containing the metallic element.
    Type: Grant
    Filed: May 23, 2003
    Date of Patent: January 29, 2008
    Assignee: Cabot Corporation
    Inventors: Bart F. Bakke, David Madden
  • Patent number: 7041268
    Abstract: The present invention is directed to a novel integrated process for the recovery of sulphate of potash (SOP) from sulphate rich bittern. The process requires bittern and lime as raw materials. Kainite type mixed salt is obtained by fractional crystallization of the bittern, and is converted to schoenite which is subsequently reacted with muriate of potash (MOP) for its conversion to SOP. End liquor from kainite to schoenite conversion (SEL) is desulphated and supplemented with MgCl2 using end bittern generated in the process of making carnallite. Decomposed carnallite liquor produced is reacted with hydrated lime for preparing CaCl2 solution and high purity Mg(OH)2 having low boron content. It is shown that the liquid streams containing potash are recycled in the process, and the recovery of potash in the form of SOP is quantitative.
    Type: Grant
    Filed: March 30, 2004
    Date of Patent: May 9, 2006
    Assignee: Council of Scientific and Industrial Research
    Inventors: Pushpito Kumar Ghosh, Kaushik Jethalal Langalia, Maheshkumar Ramniklal Gandhi, Rohit Harshadray Dave, Himanshu Labhshanker Joshi, Rajinder Nath Vohra, Vadakke Puthoor Mohandas, Sohan Lal Daga, Koushik Halder, Hasina Hajibhai Deraiya, Ramjibhai Devjibhai Rathod, Abdulhamid Usmanbhai Hamidani
  • Patent number: 6652603
    Abstract: A method for removing sodium sulfate from nickel and ammonia containing aqueous effluents. The effluents, typically from a nickel hydroxide production process, are cooled to or below 30° C. to crystallize and precipitate the sodium sulfate and dewater the effluent. The sodium sulfate is retrieved and the remaining solution is recycled back to the nickel hydroxide production process.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: November 25, 2003
    Assignee: Inco Limited
    Inventors: Juraj Babjak, Feng Zou
  • Patent number: 6419887
    Abstract: A process for the treatment of residual liquors from the ammoniation and carbonation of alkali metal salts containing ammonium salts, sodium salts, soluble sodium bicarbonate, ammonium bicarbonate and water and producing purified ammonium salts, comprising the steps of: eliminating the sodium bicarbonate, and ammonium bicarbonate mixed in the residual liquor by mixing sulfuric acid with the residual liquor in order to obtain a solution of an ammonium salt and a sodium salt; and separating the sodium salt from the solution or mixing the solution with sodium chloride crystals in order to obtain a magma containing sodium salt crystals and ammonium chloride crystals and separating the sodium salt crystals and the ammonium chloride crystals from the magma.
    Type: Grant
    Filed: May 8, 2000
    Date of Patent: July 16, 2002
    Inventor: José Cabello-Fuentes
  • Patent number: 6180074
    Abstract: A method for removing contaminants, such as sulfur dioxide, mercury and hydrochloric acid, out of flue gases is provided, said method including the steps of: treating the flue gases with a reagent, such as sodium carbonate, sodium bicarbonate and ammonium salts or mixtures thereof; selectively dissolving the sodium phosphates produced thereby in water; separating out the solids remaining in suspension in the solution; and crystallizing the purified sodium sulphate present in the above-mentioned solution. The sodium sulfate can be upgraded in glass working furnaces. The reagent can be obtained by heating an intermediate solution containing sodium bicarbonate; sodium carbonate; ammonium bicarbonate and ammonium carbonate, which was obtained from the Solvay process for manufacturing sodium carbonate.
    Type: Grant
    Filed: August 14, 1998
    Date of Patent: January 30, 2001
    Assignee: Novacarb
    Inventors: Fabrice Fourcot, Jean-Claude Pouxviel
  • Patent number: 6177056
    Abstract: A process for recovery of substantially all the sulfur in a spent lead-acid battery as Na2SO4 is disclosed. The process comprises (a) breaking the batteries to remove the acid, (b) separating the plastic from the lead bearing materials, (c) smelting the lead bearing materials in a reverberatory furnace in an oxidizing atmosphere to volatilize most of the sulfur in the feed as SO2, (d) scrubbing the SO2 from the off gas stream using a soluble alkaline material such as NaOH, Na2CO3, or KOH to produce a soluble sulfite solution, (e) oxidizing the sulfite solution to sulfate, preferably by turbulent mixing of the solution with air, (f) adjusting the pH by adding the sulfuric acid separated from the batteries, (g) removing the contained heavy metals, (h) crystallizing the sulfate as Na2SO4 or K2SO4, (i) separating a bleed stream from the crystallizer and removing the contained chlorides as a mixed sulfate-chloride product by evaporation of the bleed stream in another crystallizer.
    Type: Grant
    Filed: January 13, 1999
    Date of Patent: January 23, 2001
    Assignee: RSR Corporation
    Inventors: R. David Prengaman, Clifford E. Morgan, Homer P. Hine, Gerald M. Griffin, Jr.
  • Patent number: 6143271
    Abstract: The present invention provides a process for producing potassium sulfate from a potash and a sodium sulfate source, comprising the steps of: (a) treating a portion of the potash source and sodium sulfate source, such that glaserite is crystallized out of solution and a first mother liquor is produced; (b) converting the glaserite to precipitate potassium sulfate in a second mother liquor; (c) recycling the second mother liquor to the portion of the potash source and sodium sulfate source; (d) subjecting the first mother liquor to evaporative crystallization to produce sodium chloride in a third mother liquor; and (e) recycling the third mother liquor to the portion of the potash source and sodium sulfate source.
    Type: Grant
    Filed: September 14, 1998
    Date of Patent: November 7, 2000
    Assignee: Dead Sea Works
    Inventors: Curt Holdengraber, Shalom Lampert
  • Patent number: 6056813
    Abstract: A process for making white pigment directly from constituent materials without byproducts. The process comprises the steps of inputting three material flows comprising a sulphate source, an alkali source, and an aluminum source. And, recycling and mixing into the three material flows a process return from a separation and wash stage and vapors from a pressure let-down stage. This is followed by heating and holding a mixture of recycled process returns and the three material flows at elevated pressure in a reactor for a minimum predetermined residence time. Afterwards, letting down pressure in a flow from the reactor to produce a pre-wash flow. Then, separating, classifying, and delaminating the pre-wash flow into a first and second pigment or filler that are differentiated by their respective average particle distribution sizes.
    Type: Grant
    Filed: December 14, 1998
    Date of Patent: May 2, 2000
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar, Jerry V. Fox, Fred A. Aiken, III
  • Patent number: 6053963
    Abstract: The present invention provides a method for treating rotary slag containing iron and sodium compounds. The method involves treating the slag in a sulfuric acid solution to convert the iron and sodium within the slag to iron sulfate and sodium sulfate. The iron sulfate (along with substantially all of the heavy metal contaminants) forms a precipitate, while the sodium sulfate remains in solution. The precipitate can then be separated from the solution.
    Type: Grant
    Filed: May 21, 1998
    Date of Patent: April 25, 2000
    Assignee: GNB Technologies, Inc.
    Inventor: Paul R. Graves, Jr.
  • Patent number: 5895523
    Abstract: A process is provided for making K.sub.2 SO.sub.4 3Al.sub.2 O.sub.3 4S0.sub.3 +xH.sub.2 O or Na.sub.2 SO.sub.4 3Al.sub.2 O.sub.3 4SO.sub.3 +xH.sub.2 O where x is a number from 4 to 12, which is used as a pigment. Sulfuric acid, one of a sulfate salt or a hydroxide of either potassium or sodium and one of a sulfate of aluminum or a hydroxide of aluminum are inputted into a crystallizer and reacted to form either Al.sub.2 (SO.sub.4).sub.3 K.sub.2 SO.sub.4 +24H.sub.2 O or Al.sub.2 (SO.sub.4).sub.3 Na.sub.2 SO.sub.4 +24H.sub.2 O. A fluid flow containing either Al.sub.2 (SO.sub.4).sub.3 K.sub.2 SO.sub.4 +24H.sub.2 O or Al.sub.2 (SO.sub.4).sub.3 Na.sub.2 SO.sub.4 +24H.sub.2 O is drawn off from the crystallizer and transferred into a pigment reactor where it is subjected to a temperature of about 200.degree. C. and a pressure ranging from 120 to 350 pounds per square inch so as to result in the production of either basic potassium aluminum sulfate K.sub.2 SO.sub.4 3Al.sub.2 O.sub.3 4SO.sub.3 +xH.sub.
    Type: Grant
    Filed: December 24, 1997
    Date of Patent: April 20, 1999
    Assignee: Solv-Ex Corporation
    Inventors: John S. Rendall, Massoud Ahghar, Jerry V. Fox
  • Patent number: 5665324
    Abstract: Valuable substances are recovered from a spent electroless nickel plating solution containing a water-soluble nickel salt, organic complexing agent, hypophosphite, phosphite, and alkali metal ion by adding oxalic acid to the plating solution for causing a nickel ion to precipitate as nickel oxalate for removal and recovery; optionally adding a sulfide to the plating solution for causing a heavy metal ion to precipitate as a heavy metal sulfide for removal; adding a mineral acid and calcium oxide, calcium hydroxide, calcium carbonate, calcium sulfate, calcium chloride or a calcium salt of organic acid to the plating solution from which the nickel ion has been removed; firing solids of the solution in air for converting the alkali metal ion into an alkali metal salt of mineral acid, converting phosphorus into hydroxyapatite, and pyrolyzing off the organic material; and pouring a solid mixture of the alkali metal salt of mineral acid and hydroxyapatite into water for dissolving the alkali metal salt of mineral a
    Type: Grant
    Filed: July 14, 1995
    Date of Patent: September 9, 1997
    Assignees: Taihei Chemical Industrial Co., Ltd., C. Uyemura & Co., Ltd.
    Inventors: Teruyoshi Izawa, Kazunori Kudo, Yoshihiro Kani, Ken Araki, Tamotsu Kato, Takashi Furui
  • Patent number: 5624649
    Abstract: A wet flue gas desulfurization process and system are provided for removing sulfur dioxide from flue gases produced by processing operations of the type carried out in utility and industrial plants. In particular, the desulfurization process utilizes an ammonia-based solution having a free ammonia constituent that reacts with sulfur dioxide to generate an ammonium sulfate solution that can be further reacted to produce potassium sulfate, a valuable fertilizer. A second byproduct of this process is then reacted to regenerate free gaseous ammonia, which can then be recovered for subsequent use in the desulfurization of flue gases.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: April 29, 1997
    Assignee: General Electric Co.
    Inventor: Eli Gal
  • Patent number: 5552126
    Abstract: A process for producing potassium sulfate, sodium sulfate, and sodium chloride from potash and a sodium sulfate/water source, which includes: (a) treating the sodium sulfate/water source to produce a slurry containing anhydrous sodium sulfate; (b) concentrating the slurry to form a concentrate and a diluent; (c) treating the diluent to precipitate out anhydrous sodium sulfate; (d) subjecting the anhydrous sodium sulfate from steps (b) and/or (c) and/or from a different source to conversion with potash in an aqueous medium to yield glaserite and a first mother liquor, with any excess anhydrous sodium sulfate being taken as co-product; (e) converting the glaserite with potash and water to produce a precipitate of potassium sulfate and a second mother liquor; (f) returning the second mother liquor to step (d); (g) subjecting the first mother liquor to evaporative crystallization such that substantially pure sodium chloride is precipitated in a third mother liquor; and (h) returning the third mother liquor for co
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: September 3, 1996
    Assignee: Dead Sea Works Ltd.
    Inventors: Itzhak Efraim, Shalom Lampert, Curt Holdengraber
  • Patent number: 5549876
    Abstract: A process for the manufacture of potassium sulfate from a sodium sulfate source, potash and water, comprising the steps of: (a) introducing the sodium sulfate source, water and potash into a differential countercurrent contactor; and (b) causing the sodium sulfate source, potash and water to contact differentially to produce potassium sulfate.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: August 27, 1996
    Assignee: Dead Sea Works
    Inventors: Tuvia Zisner, Curt Holdengraber, Shalom Lampert
  • Patent number: 5529764
    Abstract: A process for producing potassium sulfate or potassium sulfate and sodium sulfate from potash and a sodium sulfate/water source, which includes: (a) subjecting a sodium sulfate source to conversion with potash in an aqueous medium to yield glaserite precipitate and a first mother liquor; (b) converting the glaserite precipitate with potash and water to produce a potassium sulfate precipitate and a second mother liquor; (c) returning the second mother liquor to step (a); (d) subjecting the first mother liquor to treatment, such as evaporative crystallization, such that a sodium chloride and sodium sulfate solids mixture or pure sodium chloride is precipitated in a third mother liquor; (e) subjecting the solids from step (d) to a sodium sulfate/water source to produce anhydrous sodium sulfate; and (f) returning the third mother liquor for conversion to potassium salts.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: June 25, 1996
    Assignee: Dead Sea Works Ltd.
    Inventors: Shalom Lampert, Curt Holdengraber
  • Patent number: 5221528
    Abstract: In a purification process for brine, impurities such as calcium, magnesium and/or sulphate are precipitated by the addition of calcium hydroxide (Ca(OH).sub.2) and sodium carbonate (Na.sub.2 CO.sub.3). Following NaCl crystallization by evaporation of the brine, a mother liquor is obtained which still contains among others sulphate, potassium and bromide ions. Further concentration of this mother liquor by evaporation results in the precipitation of both NaCl and Na.sub.2 SO.sub.4 and a more strongly concentrated mother liquor with respect to both potassium and bromide remains. This concentrated mother liquor is drained off. Either the precipitated NaCl and Na.sub.2 SO.sub.4 are dissolved in water or the Na.sub.2 SO.sub.4 is dissolved in purified brine or crude brine and then returned to the brine purification process, thereby lowering both the potassium and bromide ion levels in the purified brine. As a consequence the contents of both potassium and bromide of the NaCl are reduced.
    Type: Grant
    Filed: December 27, 1991
    Date of Patent: June 22, 1993
    Assignee: Akzo N.V.
    Inventor: Pieter Jongema
  • Patent number: 4804498
    Abstract: A soluble salt (sodium sulfate or sodium borate (Na.sub.2 SO.sub.4 or Na.sub.2 B.sub.4 O.sub.7) contained as the main component in a concentrated radioactive waste liquid generated in the BWR power plant or the PWR power plant is insolubilized and precipitated, sodium hydroxide (NaOH formed in the insolubilization is separated from the precipitate and the radioactive waste liquid slurry containing the precipitate is solidified with a hydraulic solidifying material. Since the separated caustic soda (NaOH) is free of radioactive substances, it can be easily utilized again, and since the radioactive substances are stably fixed in the solidified body, leakage of radioactivity from the solidified body can be greatly reduced.
    Type: Grant
    Filed: December 8, 1986
    Date of Patent: February 14, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Hiroko Mizuno, Makoto Kikuchi, Shin Tamata, Tatsuo Izumida, Tsutomu Baba
  • Patent number: 4636376
    Abstract: A process for the removal of essentially chromium-free sulfate from a chromate and sulfate-containing chlorate liquor which includes mixing the chlorate liquor having a pH of between about 2.0 and 6.0 with a calcium-containing material at a temperature and for a time sufficient to form a sulfate-containing precipitate predominantly of glauberite, Na.sub.2 Ca(SO.sub.4).sub.2, and separating the substantially chromium-free glauberite from the chlorate liquor.
    Type: Grant
    Filed: September 30, 1985
    Date of Patent: January 13, 1987
    Assignee: PPG Industries, Inc.
    Inventors: Bernard A. Maloney, John E. Carbaugh
  • 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: 4554151
    Abstract: A process for producing K.sub.2 SO.sub.4 from potassium chloride salts, calcium sulfate salts and another sulfate source wherein syngenite is formed and then decomposed with mineral acid to produce crystalline K.sub.3 H(SO.sub.4).sub.2. The K.sub.3 H(SO.sub.4).sub.2 crystals are recrystallized to produce K.sub.2 SO.sub.4 crystals.
    Type: Grant
    Filed: September 27, 1983
    Date of Patent: November 19, 1985
    Assignee: Prodeco, Inc.
    Inventors: Ralph E. Worthington, Alex Magdics, Donald B. Stain
  • Patent number: 4533536
    Abstract: Process for the manufacture of potassium sulphate from solutions containing magnesium chloride and potassium chloride from solutions, more particularly from mother liquors issuing from the treatment of carnallite. According to this process sodium sulphate and potassium chloride are added to the solutions so as to precipitate sodium chloride and schoenite (K.sub.2 SO.sub.4.MgSO.sub.4.6H.sub.2 O) and the schoenite is treated in a known manner to produce potassium sulphate.
    Type: Grant
    Filed: March 11, 1983
    Date of Patent: August 6, 1985
    Assignee: Mines de Potasse d'Alsace S.A.
    Inventors: Michel Bichara, Emile Wendling, Michel Bodu
  • Patent number: 4466950
    Abstract: Cesium is recovered from cesium alum, CsAl(SO.sub.4).sub.2, by a two-reaction sequence in which the cesium alum is first dissolved in an aqueous hydroxide solution to form cesium alum hydroxide, CsAl(OH).sub.3, and potassium sulfate, K.sub.2 SO.sub.4. Part of the K.sub.2 SO.sub.4 precipitates and is separated from the supernatant solution. In the second reaction, a water-soluble permanganate, such as potassium permanganate, KMnO.sub.4, is added to the supernatant. This reaction forms a precipitate of cesium permanganate, CsMnO.sub.4. This precipitate may be separated from the residual solution to obtain cesium permanganate of high purity, which can be sold as a product or converted into other cesium compounds.
    Type: Grant
    Filed: July 12, 1983
    Date of Patent: August 21, 1984
    Assignee: Carus Corporation
    Inventor: Peter G. Mein
  • Patent number: 4451439
    Abstract: A process for the purification of solutions containing sodium or potassium carbonate, sulphate, hydroxide or hydrogen carbonate, and mainly at least one of the metals belonging to the group formed by vanadium, uranium or molybdenum, in the form of sodium or potassium salts, and inorganic and/or organic impurities, wherein the above-mentioned solutions are completely or partially caustified by the addition of an adequate amount of lime, whereby a first precipitate essentially containing calcium carbonate is separated, and the separated liquor is concentrated by evaporation until the hydroxide content is at most equal to 50%, to cause the production of a second precipitate which essentially comprises sodium or potassium sulphate, then, after separation thereof, a hydroxide-rich liquor is collected.This process is more particularly adapted for treatments of liquors resulting from the alkaline attach of vanadiferous and uraniferous ores.
    Type: Grant
    Filed: November 23, 1981
    Date of Patent: May 29, 1984
    Assignee: Pechiney
    Inventors: Pierre Maurel, Bernard Bosca, Francois Nicolas
  • Patent number: 4265863
    Abstract: A process and installation for the integrated treatment of concentrated residual solutions resulting from the anodization of aluminium parts is described, in which caustic soda is employed in the pickling process and sulphuric acid in the anodization bath.The process comprises three sets of operations:(1) Production of aluminium sulphate in concentrated solution or in hydrated crystals, by the treatment of part of the residual solution from the anodization.(2) Production of precipitated aluminium hydroxide and a solution of sodium sulphate from residual anodization and pickling solutions.(3) Production of sodium aluminate from residual pickling solutions and aluminium hydroxide producted in (2). (FIG. 1.
    Type: Grant
    Filed: April 3, 1979
    Date of Patent: May 5, 1981
    Assignee: Exergie Societe de Personnes a Responsabilitie Limitee
    Inventor: Samuel J. Wajc
  • Patent number: 4230678
    Abstract: An improvement in processes for recovering aluminum from alunite ore which processes include roasting the ore to remove water of hydration, removing sulfur and potassium compounds from the roasted ore by a procedure including a first leaching step resulting in a residue and a solution containing potassium sulfate, effecting partial recovery of potassium sulfate from the solution by crystallization with some potassium sulfate being bled off from the mother liquor, converting aluminum values in the residue to alkali metal aluminates by digesting the residue with alkali metal hydroxide including a substantial amount of sodium hydroxide, removing silicon from the alkali metal aluminates leaving a waste desilication product, recovering aluminum values from the desilicated aluminates by precipitation, circulating the mother liquor from the precipitation step to digestion as contaminated sodium hydroxide is bled off, the improvement which comprises enhancing the economics of the overall process by introducing therei
    Type: Grant
    Filed: February 14, 1979
    Date of Patent: October 28, 1980
    Assignees: Earth Sciences, Inc., National Steel Corporation, Southwire Company
    Inventors: George J. Hartman, Vernon R. Ewing
  • 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
  • Patent number: 4180547
    Abstract: A continuous process for the recovery of chemicals in saline water including the steps of converting the sulfates in the saline water feed to sodium sulfate; separating and recovering in the oxide forms essentially all of the magnesium and calcium from the saline water feed; then preparing a sodium chloride fortified solution by mixing the feed with recycled sodium chloride; crystallizing and re-crystallizing and then separating sodium chloride crystals, preferably in two evaporative crystallization processes; stripping bromine from the sodium chloride depleted solution; crystallizing and then separating sodium chloride and sodium sulfate crystals from each other and then from solution; recycling the separated sodium chloride to the first sodium chloride crystallization step; separating residual sulfates from the solution; crystallizing and then separating sodium chloride crystals; recycling the separated sodium chloride to the first sodium chloride crystallization step; crystallizing and then separating pota
    Type: Grant
    Filed: November 25, 1977
    Date of Patent: December 25, 1979
    Assignee: Ecodyne
    Inventor: Anthony N. Chirico
  • Patent number: 4132759
    Abstract: In the process for the production of chlorine and alkali metal hydroxide by electrolysis according to the amalgam process using calcium- and/or sulphate containing crude salt, the calcium and/or sulphate contents introduced into the brine circuit by the crude salt are removed from the brine by precipitation of the double salt Na.sub.2 SO.sub.4 . CaSO.sub.4. Small particles of glauberite may be introduced to the brine to initiate and accellerate precipitation.
    Type: Grant
    Filed: February 28, 1978
    Date of Patent: January 2, 1979
    Assignee: Bayer Aktiengesellschaft
    Inventor: Rolf Schafer
  • Patent number: 4129642
    Abstract: Potassium sulfate is produced from a mixture of carnallite, potassium chloride, kieserite and residual quantities of less than 15% by weight of rock salt by treating the mixture at a temperature of 20.degree.-40.degree. C with potash magnesia liquor to form a slurry with at most 70 mole MgCl.sub.2 /1000 mole H.sub.2 O, whereafter the liquor portion of the slurry comprising a solution saturated with carnallite and rock salt is separated from the solid substance, which solid substance is then converted at temperatures of 75.degree.-110.degree. with a sulfate liquor, which contains 18-45 mole MgCl.sub.2 /1000 mole H.sub.2 O, into a mixture of langbeinite and potassium chloride, which mixture after separation from the liquor is treated at temperatures of 15.degree.-110.degree. C with a sulfate liquor containing 18-50 mole MgCl.sub.2 /1000 mole H.sub.2 O, whereupon the crystallizate is separated from the mother liquor and is converted with water to potassium sulfate.
    Type: Grant
    Filed: July 19, 1977
    Date of Patent: December 12, 1978
    Assignee: Kali & Salz AG
    Inventor: Ulrich Neitzel
  • Patent number: 4119528
    Abstract: A process for the simultaneous desulfurization and hydroconversion of heavy carbonaceous feeds, including various sulfur-containing heavy petroleum oils, is disclosed. These feedstocks are contacted with potassium sulfide in a conversion zone maintained at elevated temperatures and in the presence of added hydrogen. In this manner, the feeds are substantially desulfurized, and significant upgrading of these feeds is also obtained as demonstrated by decreased Conradson carbon, increased API gravity, and the conversion of substantial portion of the 1,050.degree. F.+ portion of these feeds. In a preferred embodiment, such a process is disclosed employing a combination of potassium sulfide and sodium sulfide, and in particular these processes include procedures for the regeneration of the sulfides and their recycle to the conversion zone.
    Type: Grant
    Filed: August 1, 1977
    Date of Patent: October 10, 1978
    Assignee: Exxon Research & Engineering Co.
    Inventors: William C. Baird, Jr., Roby Bearden, Jr.
  • Patent number: 4119698
    Abstract: The red mud by-product of the Bayer process by which aluminum oxide is reed from bauxite as an aluminate, is digested with concentrated sulfuric acid or with sulfur trioxide gas to produce sulfates that can be leached out to the resulting mass with water. The solution is then heated at a pH of 1 to precipitate titanium oxide hydrate by hydrolysis. The remaining sulfates of the solution are then obtained in solid form by evaporation, or by precipitation with acetone, and the solid is then roasted to convert the aluminum and iron to the oxide. After leaching out the sodium sulfate with water, the aluminum and iron oxide are separated by the Bayer process, which works in this case even though x-ray diffusion patterns show that the aluminum oxide is mainly .alpha.Al.sub.2 O.sub.3.
    Type: Grant
    Filed: March 6, 1978
    Date of Patent: October 10, 1978
    Assignees: Kernforschungsanlage Julich, Gesellschaft mit beschrankter Haftung, Vereinigte Aluminum-Werke Aktiengesellschaft
    Inventors: Erich Zimmer, Ahmad Nafissi, Gunther Winkhaus
  • Patent number: 4117077
    Abstract: A process for alunite ore treatment which comprises roasting alunite in the presence of oxygen at a temperature of from 580.degree. to 620.degree. C. for 1 to 3 hours, decomposing the roasted alunite by exposure to reducing agents at a temperature of from 580.degree. to 620.degree. C., subjecting the reduced alunite to hydrochemical treatment by use of a sodium hydroxide solution of concentration from 100 to 150 g/lit in terms of Na.sub.2 O, decomposing the resultant aluminate liquor, with the aluminum hydroxide component precipitating out, and finally, washing and baking the aluminum hydroxide precipitate to obtain same as an end product. The invention provides a comprehensive method of treatment of alunite ores the associated rock whereof comprises silica in the form of opal and chalcedony earlier believed to be refractory to comprehensive treatment by alkaline methods.
    Type: Grant
    Filed: November 23, 1977
    Date of Patent: September 26, 1978
    Inventors: Gakif Zakirovich Nasyrov, Evgenia Ivanovna Zemlyanskaya, Izabella Vladislavovna Ravdonikas
  • Patent number: 4104365
    Abstract: A method of separating sulfuric acid from spent chlorine dioxide generator liquor. The method comprises simultaneously adding to the spent liquor, a water-soluble organic compound selected from the group consisting of alcohols and ketones, and water. The resulting solid is separated to leave an aqueous solution of sulfuric acid. The method is of particular application in acid and salt cake recovery from the effluent of a chlorine dioxide generator operating at an acid normality of between 6 and 11.
    Type: Grant
    Filed: May 9, 1977
    Date of Patent: August 1, 1978
    Inventors: John Howard, Derek Gordon Lobley
  • Patent number: 4083931
    Abstract: A process for treating and recovering components from aldol-condensation polyol waste liquor containing sodium formate, water, polyol, and organic by-products comprising A. vacuum crystallizing and removing sodium formate; B. introducing methanol and sulfuric acid; C. distilling to remove and recover methyl formate; D. increasing the pH to about 6.5 to 7.0; E. cooling to precipitate Glauber's salt, polyol and organics; and F. adding water to dissolve and separate the Glauber's salt and recover substantially pure polyol and organics.
    Type: Grant
    Filed: August 23, 1976
    Date of Patent: April 11, 1978
    Assignee: Industrial Sales and Factoring Corporation
    Inventor: Fu-Ming Lee
  • Patent number: 4064217
    Abstract: An improvement in the process for recovering aluminum from alunite ore disclosed in U.S. Pat. Nos. 3,890,425 and 3,890,426, the improvement being in the recovery of potassium sulfate by crystallization from the leaching solution resulting from potassium hydroxide leaching of the roasted ore, the improvement consisting of adding potassium hydroxide to the concentrated leach liquor prior to crystallization to increase the concentration of the potassium ion so that increased recoveries of potassium sulfate are obtained at a given temperature over those obtained when this procedure is not used. By this procedure a yield is obtained at a temperature below that which is required to obtain the same yield when potassium hydroxide is not used so that the high temperatures formerly necessary to hold enough potassium sulfate in solution for an economic crystallization are avoided.
    Type: Grant
    Filed: September 30, 1976
    Date of Patent: December 20, 1977
    Inventors: George J. Hartman, Michael G. Darland
  • Patent number: 4042674
    Abstract: In the production of anhydrous sodium dithionite by reacting sodium formate, an alkaline sodium compound and sulfurous acid anhydride in hydrous methanol, a process for treating the mother liquor, which comprises cooling the mother liquor left after the separation of the resulting anhydrous sodium dithionite to a temperature in the range of +5.degree. to -30.degree. C, and separating the precipitated sodium thiosulfate by filtration.
    Type: Grant
    Filed: May 18, 1976
    Date of Patent: August 16, 1977
    Assignee: Mitsui Toatsu Chemicals Inc.
    Inventors: Kousuke Yamamoto, Shinji Takenaka, Kazuo Maeda
  • Patent number: 4042675
    Abstract: In the production of anhydrous sodium dithionite by reacting sodium formate, an alkaline sodium compound and sulfurous acid anhydride in hydrous methanol, a process for treating the mother liquor, which comprises adding an alkali to the mother liquor left after the separation of the resulting anhydrous sodium dithionite to adjust its pH to at least 8, separating the solids precipitated, and oxidizing the filtrate with an oxidizing agent.
    Type: Grant
    Filed: May 18, 1975
    Date of Patent: August 16, 1977
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Kousuke Yamamoto, Shinji Takenaka, Kazuo Maeda, Michio Mituta
  • Patent number: 3996334
    Abstract: An improvement in processes for recovering aluminum from alunite ore which processes include roasting the ore to remove water of hydration, removing sulfur and potassium compounds from the roasted ore by a procedure including a final leaching step resulting in a residue and a solution containing potassium sulfate, effecting partial recovery of potassium sulfate from the solution by crystallization with some potassium sulfate being bled off from the mother liquor, converting aluminum values in the residue to alkali metal aluminates by digesting the residue with alkali metal hydroxide including a substantial amount of sodium hydroxide, removing silicon from the alkali metal aluminates leaving a waste desilication product, recovering aluminum values from the desilicated aluminates by precipitation, circulating the mother liquor from the precipitation step to digestion as contaminated sodium hydroxide is bled off, the improvement which comprises enhancing the economics of the overall process by introducing therei
    Type: Grant
    Filed: June 2, 1975
    Date of Patent: December 7, 1976
    Assignees: Southwire Company, National Steel Corporation, Earth Sciences, Inc.
    Inventors: George J. Hartman, Vernon R. Ewing
  • Patent number: RE32556
    Abstract: Cesium is recovered from cesium alum, CsAl(SO.sub.4).sub.2, by a two-reaction sequence in which the cesium alum is first dissolved in an aqueous hydroxide solution to form cesium alum hydroxide, CsAl(OH).sub.3, and potassium sulfate, K.sub.2 SO.sub.4. Part of the K.sub.2 SO.sub.4 precipitates and is separated from the supernatant solution. In the second reaction, a water-soluble permanganate, such as potassium permanganate, KMnO.sub.4, is added to the supernatant. This reaction forms a precipitate of cesium permanganate, CsMnO.sub.4. This precipitate may be separated from the residual solution to obtain cesium permanganate of high purity, which can be sold as a product or converted into other cesium compounds.
    Type: Grant
    Filed: July 28, 1986
    Date of Patent: December 8, 1987
    Inventor: Peter G. Mein