Ferric Oxide Patents (Class 423/633)
  • Patent number: 4049788
    Abstract: A process for the thermal decomposition and conversion of metal chlorides to metal oxides in a fluidized bed wherein the fluidizing gas contains oxygen and the reaction temperature is maintained above the thermal decomposition temperature of the metal chloride but below the sintering temperature of the metal oxide thus produced. The gas velocity is determined by the critical relationship 0.34.rho..sup.0.9 .ltoreq. W.sub.G .ltoreq. 0.56.rho..sup.0.9 where W.sub.G is the approximate gas velocity through the fluidized bed chamber in the absence of the bed and .rho. is the density of the pure fluidized-bedmaterial (metal oxide). The height of the bed is also critical and should be that at which a critical pressure drop of 1200 to 2400 mm (water column) is obtained but at least 350 mm, measuring with the static or settled bed (nonfluidized).
    Type: Grant
    Filed: October 17, 1975
    Date of Patent: September 20, 1977
    Assignee: Metallgesellschaft Aktiengesellschaft
    Inventors: Herbert Bierbach, Heinz Dittmar, Ernst Heinz, Klaus Hohmann, Rolf Rennhack
  • Patent number: 4048283
    Abstract: Aqueous process streams or waste waters destined for merging with public waters sometimes contain deleterious amounts of heavy metals, e.g., lead (Pb) compounds. The heavy metal compounds may be substantially removed or reduced to harmless levels by treating the acidic aqueous streams with chromate or dichromate ions, then heating the solution to oxidize organics and/or heavy metal-organics, then raising the pH to an alkaline pH to precipitate the heavy metal chromate, and separating the heavy metal chromate from the aqueous stream.
    Type: Grant
    Filed: June 4, 1976
    Date of Patent: September 13, 1977
    Assignee: The Dow Chemical Company
    Inventor: John Malcolm Lee
  • Patent number: 4046853
    Abstract: The simultaneous chlorination of the iron and titanium values in an iron containing titaniferous ore such as ilmenite is advantageously conducted to convert the iron values to ferrous chloride but the resulting gaseous effluent is difficult to process to recover the titanium tetrachloride. The iron values in the effluent are partially oxidized according to the equation3FeCl.sub.2 + 3/4O.sub.2 .fwdarw. 1/2Fe.sub.2 O.sub.3 + 2FeCl.sub.3thereby reducing the vapor partial pressure of the ferrous chloride while maintaining the presence of some ferrous chloride to scavenge any chlorine emitted from the chlorination stage. The residual gaseous iron chlorides are condensed and chlorine-free titanium tetrachloride may be recovered from the remaining gases. If chlorine-free titanium tetrachloride is not required the mixture of gases resulting from the partial oxidation are reduced in temperature of from 500.degree. C to 800.degree.
    Type: Grant
    Filed: June 15, 1976
    Date of Patent: September 6, 1977
    Assignee: Laporte Industries Limited
    Inventor: Michael Robinson
  • Patent number: 4046854
    Abstract: The recovery of titanium tetrachloride from a mixed titanium tetrachloride/ferric chloride vapor, suitably as produced by the fluidized bed chlorination of an iron containing titaniferous ore such as ilmenite is by treating the vapor with excess oxygen over that required in theory to oxidize the ferric chloride content thereof while maintaining the vapor at a temperature within the range of 500.degree. C to 800.degree. C, removing the resulting ferric oxide particles from the vapor, cooling the vapor to a temperature above the boiling point of titanium tetrachloride to condense residual ferric chloride in the vapor and separating the condensed ferric chloride, and recovering the remaining titanium tetrachloride containing vapor.The residual ferric chloride, and chlorine remaining in the vapor after recovery of the titanium tetrachloride may be recycled.
    Type: Grant
    Filed: June 15, 1976
    Date of Patent: September 6, 1977
    Assignee: Laporte Industries Limited
    Inventor: John Dunderdale
  • Patent number: 4042501
    Abstract: Iron containing aqueous, acidic solutions, such as acidic stripping solutions used to remove iron from organic extractants, are purified by subjecting the acidic solution to a hydrothermal treatment at elevated temperatures and pressures which cause the precipitation of the dissolved iron in easily separable form. The hydrothermal treatment is accomplished at temperatures in excess of about 100.degree. C. The process can be applied to acidic solutions containing the dissolved iron in the form of ferric sulfate, ferric nitrate or chloride and is particularly adaptable to acidic stripping solutions resulting from the purification of organic extractants employed to extract iron impurities from solutions obtained in the acid leaching of clays, ores and concentrates.
    Type: Grant
    Filed: July 2, 1976
    Date of Patent: August 16, 1977
    Assignee: Kaiser Aluminum & Chemical Corporation
    Inventor: William R. King
  • Patent number: 4026773
    Abstract: Metal values are extracted from manganiferous ocean floor nodule ore by treating the ore with hydrochloric acid, thereby producing chlorine and a starting pulp containing a solution of the metal chlorides and a solid residue. The starting pulp is subjected to at least two subsequent acidifications with HCl, each acidification being followed by addition of fresh ore, thereby producing chlorine and a final pulp containing a concentrated solution of metal chlorides and a solid residue. The solid residue is separated from the concentrated solution and substantially all the metal values, except manganese and alkali and alkaline earth metals, are separated from the solution. The manganese is separated from the solution by treatment with chlorine, at least the major portion of which was produced in the preceding leaching steps, while maintaining the solution at a pH of between about 3 and 7 by addition of a neutralizing agent such as MgO or Mg(OH).sub.2 whereby the manganese is precipitated in the form of MnO.sub.
    Type: Grant
    Filed: January 14, 1976
    Date of Patent: May 31, 1977
    Assignee: Metallurgie Hoboken Overpelt
    Inventor: Antoine L. Van Peteghem
  • Patent number: 4010242
    Abstract: Oxide microspheres having a diameter in the 0.5 to 20 micron range are produced by forming a mixture of urea or melamine and formaldehyde in an aqueous sol containing colloidal oxide particles. Copolymerization of the organic constituents produces coacervation of the organic material into microparticles containing the inorganic material. The organic constituent can be burned out to form a powder of uniform-sized porous microparticles consisting of an interconnected array of inorganic colloidal particles separated by uniform-sized pores.
    Type: Grant
    Filed: November 20, 1973
    Date of Patent: March 1, 1977
    Assignee: E. I. DuPont de Nemours and Company
    Inventors: Ralph K. Iler, Herbert J. McQueston
  • Patent number: 4006090
    Abstract: Elongated, polycrystalline particles of alpha iron oxide, characterized by an open, porous structure and consisting of hematite microcrystallites containing from 2 to 4 percent of sulfate are prepared by the reaction of lithium hydroxide and ferric sulfate in weakly acidic to neutral aqueous solution under at least autogenous pressures at temperatures in the range of 150.degree.-350.degree. C. The particles are readily converted to gamma iron oxide of good magnetic properites and also have utility as pigments and catalysts.
    Type: Grant
    Filed: July 21, 1975
    Date of Patent: February 1, 1977
    Assignee: The Dow Chemical Company
    Inventor: Henry Nelson Beck
  • Patent number: 4006213
    Abstract: A process for the extraction and recovery of hydrated stannic oxide and alkali metal ferrocyanide from the sludge formed in a halogen tin electrodeposition bath is described. The process comprises dissolving the ferrocyanide compounds and the tetravalent tin compounds present in the sludge in an alkaline medium, removing any insoluble materials, precipitating hydrated stannic oxide from the solution by neutralization of the solution, and separating the hydrated stannic oxide from the solution which then contains ferrocyanide ion together with acid and base counterions.
    Type: Grant
    Filed: July 25, 1975
    Date of Patent: February 1, 1977
    Assignee: Bethlehem Steel Corporation
    Inventors: Thomas W. Fisher, Stewart E. Rauch, Jr., Richard N. Steinbicker
  • Patent number: 3992507
    Abstract: This invention provides a halidation process for obtaining a high purity manganese oxide from a manganiferous ore, while reclaiming a substantial portion of the hydrogen halide reagent. The process comprises halidating the ore with a hydrogen halide and leaching to form the corresponding halogen and an aqueous solution comprising dissolved manganese halide and ferric halide. The hydrogen halide can be in the gaseous state and/or dissolved in the aqueous leach solution.The manganese halide and the ferric halide are preferably individually separated from the leach solution by crystallization and by selective extraction, respectively. The crystallized manganese halide is reacted with water at a temperature of from about 400.degree. C to about 700.degree. C to yield the corresponding hydrogen halide, which is recycled, and manganese oxide.In one embodiment, a concentrated leach solution is formed at a temperature of at least about 90.degree.
    Type: Grant
    Filed: April 26, 1974
    Date of Patent: November 16, 1976
    Assignee: Deepsea Ventures, Inc.
    Inventors: Paul H. Cardwell, William S. Kane
  • Patent number: 3987156
    Abstract: Ferric sulfate obtained by the oxidation of ferrous sulfate or ferric sulfate available in its original state is added to an alkali hydroxide at a ratio such that the amount of said alkali hydroxide will be in excess of its stoichiometric proportion, so as to form a pasty substance. Then, this pasty substance is subjected to a hydrothermal treatment. From the resultant product of the treatment, there are obtained micaceous .alpha.-iron oxide crystals and aqueous solutions of sodium sulfate and alkali hydroxide.
    Type: Grant
    Filed: April 25, 1975
    Date of Patent: October 19, 1976
    Assignee: Agency of Industrial Science & Technology
    Inventor: Soichiro Nobuoka
  • Patent number: 3976743
    Abstract: A process for the treatment of zinc plant residue formed on leaching zinc calcine with sulphuric acid in which the residue is leached in a first leaching step with a sulphuric acid solution at atmospheric pressure, and a temperature above about 60.degree.C, in the presence of excess zinc sulphide reductant whereby ferric iron in the residue is reduced to the ferrous state, thereby forming a zinc sulphate solution containing excess acid, ferrous iron and other dissolved impurities such as germanium, indium, gallium, antimony and arsenic nd a mixture of solids containing undigested zinc residue, lead residue, and unreacted zinc sulphide. Clarified solution is separated, preferably by thickening, from the mixture of solids. The mixture of solids is leached in a second residue leaching step at atmospheric pressure and at a temperature above about 60.degree.
    Type: Grant
    Filed: August 5, 1975
    Date of Patent: August 24, 1976
    Assignee: Cominco Ltd.
    Inventors: Louis Landucci, Donald Roderick McKay, Ernest George Parker
  • Patent number: 3974267
    Abstract: Ferrous hydroxide, formed from ferrous sulfate and sodium hydroxide at high alkalinity, is air-oxidized at a high rate to form ferric hydroxide seed crystals. The air rate is then decreased, and the seeds are allowed to grow to the desired acicular hydrated yellow ferric oxide.
    Type: Grant
    Filed: April 24, 1975
    Date of Patent: August 10, 1976
    Assignee: Cities Service Company
    Inventor: Eugene M. Urban, Jr.
  • Patent number: 3970738
    Abstract: The processes for producing iron oxide products from a solution of ferrous salts selected from the group consisting of waste liquid containing ferrous salts and aqueous solution in which ferrous salts obtained from the waste liquid are dissolved, under the acid, wet and high ferrous concentration conditions. More particularly, the processes for purifying said waste liquids comprising the bivalent iron removing steps.
    Type: Grant
    Filed: December 23, 1974
    Date of Patent: July 20, 1976
    Assignee: Toda Kogyo Corporation
    Inventors: Goro Matsui, Koji Toda, Nanao Horiishi, Kazuyoshi Wakimoto, Yoshifumi Nishiyama, Tsuneyoshi Taketa, Kazushi Takama
  • Patent number: 3969494
    Abstract: Synthetic yellow iron oxide (.alpha.-FeOOH) is dispersed in an aqueous 0 - 10N alkali solution and the resultant dispersion is subjected to a hydrothermal treatment at 100.degree.- 250.degree.C. This treatment improves the synthetic yellow iron oxide in that it converts imperfect crystals present in said iron oxide into perfect crystals, changes particles thereof from the shape of needles to that of rods, makes the particle size substantially uniform and heightens the resistivity thereof to heat by about 50.degree.C. The modified synthetic yellow iron oxide thus obtained is innoxious and can be used as a pigment in paints.
    Type: Grant
    Filed: February 21, 1975
    Date of Patent: July 13, 1976
    Assignee: Agency of Industrial Science & Technology
    Inventors: Soichiro Nobuoka, Takashi Asai, Kazuaki Ado
  • Patent number: 3954945
    Abstract: Process for the production of a finely divided oxide of a metal or silicon by the hydrolytic conversion of a volatile corresponding metal halide or silicon halide in a flame, said process comprising feeding the volatile halide in a mixture with a combustible hydrogen-containing gas and air or oxygen to a burner provided with a mouth emitting a flame, burning the mixture in a fire tube to form a first portion of water vapor, said burner surrounded by an annular chamber forming a nozzle through which hydrogen is passed to keep the mouth of the burner free of attachments of solid substances, the quantity of oxygen or air being sufficient for the practically complete combustion of the combustible gas, and the quantities of oxygen or air and combustible gas being sufficient to produce the first portion of water vapor which will at least suffice for the hydrolysis of the volatile halides, and further wherein said flame is allowed to burn in an atmosphere consisting of gases containing a second portion of water vapo
    Type: Grant
    Filed: October 27, 1972
    Date of Patent: May 4, 1976
    Assignee: Deutsche Gold- und Silber-Scheideanstalt vormals Roessler
    Inventors: Ludwig Lange, Jean Diether, Axel Volling, Hans Klebe
  • Patent number: 3947502
    Abstract: In the production of acicular, ferromagnetic iron oxide of high coercive force by oxidizing an iron (II)-hydroxide suspension with an oxygen-containing gas to form acicular iron (III) oxide hydroxide and dehydrating the iron (III) oxide hydroxide, optionally tempering, reducing and/or reoxidizing this into magnetic iron oxide, the improvement which comprises effecting the oxidation of the iron (II)-hydroxide suspension at a pH of at least about 13, the suspension including SiO.sub.2 in the form of a sol or soluble salt, the resulting iron (III) oxide hydroxide having SiO.sub.2 deposited thereon.
    Type: Grant
    Filed: January 11, 1973
    Date of Patent: March 30, 1976
    Assignee: Bayer Aktiengesellschaft
    Inventors: Lutz Leitner, Franz Hund
  • Patent number: 3946103
    Abstract: In the production of a precipitated red iron (III) oxide pigment of hematite structure wherein an aqueous iron (II) salt solution is mixed with an aqueous alkali solution in substantially equivalent quantities to produce an aqueous suspension of iron (II) hydroxide or carbonate, the suspension is oxidized by passing oxygen-containing gases through it with stirring under atmospheric pressure at a temperature of about 0.degree. to 50.degree.C, and the resulting iron (III) seed suspension is allowed to grow into precipitated red iron (III) oxide pigment by further oxidation with an oxygen-containing gas at a temperature of about 50.degree. to 100.degree.
    Type: Grant
    Filed: September 19, 1973
    Date of Patent: March 23, 1976
    Assignee: Bayer Aktiengesellschaft
    Inventor: Franz Hund
  • Patent number: 3944647
    Abstract: Vapor feed containing titanium tetrachloride and ferric chloride vapor is contacted with sodium chloride for complexing said ferric chloride as liquid sodium ferric chloride salt complex while leaving titanium tetrachloride as vapor residue. The salt complex is reacted with molecular oxygen for providing recovered chlorine gas product. Such gas can be recycled to said complexing operation for providing a high grade of chlorine and titanium tetrachloride-rich product. Substantially complete chlorination of ilmenite is a prime source of said vapor feed.
    Type: Grant
    Filed: April 8, 1974
    Date of Patent: March 16, 1976
    Assignee: SCM Corporation
    Inventor: James Paul Bonsack
  • Patent number: 3932598
    Abstract: An improved process for producing alkali metal chromates and dichromates wherein ferrochrome alloy containing at least 1% carbon by weight is reacted with a molten mixture of an alkali metal nitrate and an alkali metal carbonate at a temperature of at least 350.degree.C. The ferrochrome alloy can be prepared by smelting chromite ore in the presence of carbon.
    Type: Grant
    Filed: April 24, 1970
    Date of Patent: January 13, 1976
    Inventors: Hugh S. Cooper, deceased, Henry J. Rand, executor