Ferric Oxide Patents (Class 423/633)
  • Patent number: 4291010
    Abstract: Synthetic yellow iron oxide (.alpha.-FeOOH) is dispersed in an aqueous ferric solution, and an adequate alkali solution and an aqueous aluminum salt solution are added. The resultant dispersion is subjected to a hydrothermal treatment at 150.degree.-250.degree. C. By this treatment, the surface of the synthetic yellow iron oxide is covered with a (FeAl)OOH (solid solution). Yellow iron oxides treated thus have an elevated resistivity to heat of about 50.degree. C. The modified synthetic yellow iron oxide thus obtained is non-toxic and can be used as a pigment in plastics and melt-type traffic paint.
    Type: Grant
    Filed: September 5, 1979
    Date of Patent: September 22, 1981
    Assignee: Titan Kogyo Kabushiki Kaisha
    Inventors: Jihei Senda, Yoshihiro Inoue, Toshiaki Uenishi, Hidefumi Harada, Kouji Nakata, Akio Akagi
  • Patent number: 4289746
    Abstract: High purity hexagonal plate-like .alpha.-Fe.sub.2 O.sub.3, commonly called micaceous iron oxide, is prepared by a hydrothermal treatment of either magnetite or an iron ore, or an iron oxide, of which principal component is magnetite together with an oxidizer in an aqueous alkali solution. Main advantage of this process is a great decrease in the consumption of alkali. Pure magnetite for use in this process can be prepared economically by a hydrothermal treatment of an iron ore, or an oxide, of which principal component is an oxide of trivalent iron in an aqueous alkali solution together with a compound of divalent iron and/or metallic iron.
    Type: Grant
    Filed: May 19, 1980
    Date of Patent: September 15, 1981
    Assignee: Central Glass Company, Limited
    Inventors: Masanori Hayakawa, Satoshi Nishimura
  • Patent number: 4261966
    Abstract: Pigment grade Fe.sub.2 O.sub.3 is prepared from ferrous sulphate by a roasting process. The ferrous sulphate, partly dehydrated and granulated, is partially converted to the oxide by roasting. After elimination of soluble constituents by washing with water, the oxide is subjected to pigmentary calcination and then crushed and optionally micronized. This process makes it possible to prepare red pigments of excellent quality characterized particularly by pure tints ranging from orange-red to purplish-red. The oil absorptions are especially low. Low toxic impurity concentrations permit the use of these pigments in foodstuffs.
    Type: Grant
    Filed: October 2, 1979
    Date of Patent: April 14, 1981
    Assignee: Thann et Mulhouse, Corp.
    Inventors: Pierre Portes, Jean M. Trautmann, Daniel Hoffner
  • Patent number: 4259298
    Abstract: The invention relates to a method of recovering the chlorine values from iron chloride obtained from the chlorination of an aluminous material containing iron oxide, such as bauxite. The method involves partially dechlorinating ferric chloride in the presence of a reducing agent to form products comprising ferrous chloride and a chloride compound derived from the reducing agent and oxidizing ferrous chloride at a temperature of about 300.degree. C. to 1200.degree. C. to form products comprising ferric chloride and ferric oxide. The ferric chloride is recycled and the chlorine values are recovered as the chloride of the reducing agent which is suitable for recycle to the aluminous chlorination stage or has other industrial utility.
    Type: Grant
    Filed: May 10, 1979
    Date of Patent: March 31, 1981
    Assignee: Mineral Process Licensing Corp. B.V.
    Inventors: John H. W. Turner, Charles E. E. Shackleton
  • Patent number: 4256723
    Abstract: A precipitated red iron oxide, having high crystallinity, low acicularity, unifrom particle size, and purity of color, is produced by aerating an alkaline mixture of copperas and soda ash to form seed crystals, increasing the temperature, adding additional copperas, and aerating the mixture to form red oxide crystals of the desired color. The final color can vary from a light salmon to a dark maroon.
    Type: Grant
    Filed: May 3, 1979
    Date of Patent: March 17, 1981
    Assignee: Cities Service Company
    Inventor: Eugene M. Urban, Jr.
  • Patent number: 4255409
    Abstract: An alkali hydroxide is added to an aqueous solution of ferrous salt to form a precipitate and a part of the solution is separated to control a ratio of an anion to a ferrous component to less than 1 and the ferrous component is oxidized to acicular goethite with an alkali metal chlorate such as potassium chlorate.
    Type: Grant
    Filed: December 11, 1979
    Date of Patent: March 10, 1981
    Assignee: TDK Electronics Company Limited
    Inventors: Toshihiro Hamabata, Shinji Umeki
  • Patent number: 4251504
    Abstract: An alkali hydroxide is added to an aqueous solution of ferrous salt to form a precipitate and a part of the solution is separated to control a ratio of an anion to a ferrous component to less than 1 and the ferrous component is oxidized to acicular goethite by bubbling air through the supernatant and precipitate.
    Type: Grant
    Filed: September 20, 1979
    Date of Patent: February 17, 1981
    Assignee: TDK Electronics, Co. Ltd.
    Inventors: Toshihiro Hamabata, Shinji Umeki
  • Patent number: 4244929
    Abstract: The invention relates to the recovery of chlorine values as ferric chloride from iron chloride dust which is obtained as a by-product from the chlorination of a titaniferous material containing more than 5% by weight iron oxide, such as ilmenite. The method comprises heating the iron chloride dust to a temperature above 275.degree. C. in the presence of chlorine and iron oxide and recovering the ferric chloride volatilized from the iron chloride dust together with the ferric chloride obtained from ferrous chloride present in the iron chloride dust by reaction with the chlorine and ferric chloride obtained from other metal chloride contaminants by reaction with the iron oxide.
    Type: Grant
    Filed: May 15, 1979
    Date of Patent: January 13, 1981
    Assignee: Mineral Process Licensing Corporation BV
    Inventors: John Lumsden, Charles E. E. Shackleton
  • Patent number: 4234348
    Abstract: In the production of an iron oxide red pigment by reducing nitrobenzene with metallic iron in the presence of an acidic iron (II) salt solution, separating off the iron oxide pigment obtained from the reaction medium by washing out, and calcining the pigment at a temperature in the range of about 600.degree. to 1100.degree. C., the improvement which comprises adding an aluminum salt solution over a period of about 5 to 360 minutes at a temperature of about 20.degree. to 100.degree. C. to the iron oxide suspension accumulating during reduction of the nitrobenzene, the suspension containing about 150 to 600 g of iron/l and a residual iron (II) chloride content of about 20 to 160 g/l expressed as iron, the initial pH-value of the iron oxide suspension of about 3 to 5 being adjusted over a period of about 5 to 180 minutes to a final pH-value of about 5.5 to 6.5.
    Type: Grant
    Filed: May 22, 1979
    Date of Patent: November 18, 1980
    Assignee: Bayer Aktiengesellschaft
    Inventors: Horst Brunn, Heribert Bade, Franz Hund
  • Patent number: 4233283
    Abstract: In the manufacture of iron oxide flakes by the steps of mixing an aqueous ferric salt solution with an aqueous alkali solution for thereby inducing an amorphous precipitate and subjecting the precipitate to a hydrothermal treatment, iron oxide flakes of an increased flake size are obtained by adding boric acid or a salt thereof to the mixture prior to the step of hydrothermal treatment.
    Type: Grant
    Filed: March 15, 1979
    Date of Patent: November 11, 1980
    Assignee: Agency of Industrial Science & Technology, Ministry of International Trade & Industry
    Inventors: Kazuaki Ado, Soichiro Nobuoka, Takashi Asai
  • Patent number: 4221766
    Abstract: This process reduces the soluble iron found in the final effluent of a plant making iron oxide by the Penniman-Zoph scrap process. The finished oxide product slurry is separated from the scrap iron, and the slurry is aerated while the pH is maintained between about 3.0 and 5.0. As the soluble iron is converted to product oxide, the pH of the system rises toward the higher value.
    Type: Grant
    Filed: December 10, 1976
    Date of Patent: September 9, 1980
    Assignee: Cities Service Company
    Inventors: Wilfred A. Pabst, David Crabbe
  • Patent number: 4216196
    Abstract: Bivalent or multivalent metal chloride in aqueous solution is decomposed in the presence of oxygen to produce HCl and the corresponding metal oxide. Hydrochloric acid recovered by adiabatic absorption from the decomoposition gas is concentrated by extractive distillation in contact with concentrated metal chloride solution. The resulting solution is concentrated by heat exchange with the hot decomposition gas. At least part of the solution of high concentration is supplied to the thermal decomposition stage at a metal chloride rate corresponding to the metal chloride content of the incoming aqueous liquor.
    Type: Grant
    Filed: July 6, 1978
    Date of Patent: August 5, 1980
    Assignee: Metallgesellschaft Aktiengesellschaft
    Inventor: Klaus Hohmann
  • Patent number: 4207306
    Abstract: A novel ceramic form of hydroxylapatite and a novel ceramic product comprising a mixture of the latter and whitlockite, the preparation of these ceramics and dental restorative compositions and dental and surgical prosthetic materials containing the same are disclosed. Also described is a novel and improved process for producing polycrystalline ceramic oxides.
    Type: Grant
    Filed: December 21, 1977
    Date of Patent: June 10, 1980
    Assignee: Sterling Drug Inc.
    Inventor: Michael Jarcho
  • Patent number: 4202871
    Abstract: Single crystalline, acicular ferric oxide particles are produced by maintaining an aqueous suspension of ferric hydroxide at an elevated temperature at an alkaline pH in the presence of an organic phosphonic acid compound or a hydroxycarboxylic acid compound as a growth-regulating agent.
    Type: Grant
    Filed: November 6, 1978
    Date of Patent: May 13, 1980
    Assignee: Sakai Chemical Industry Co., Ltd.
    Inventors: Seiji Matsumoto, Tadashi Koga, Kiyoshi Fukai, Shinya Nakatani
  • Patent number: 4201761
    Abstract: A process for preparing iron oxide with a controlled purity and large particle size which comprises oxidizing at a constant pH a vigorously agitated aqueous suspension of iron oxide crystals while continuously, but slowly adding a water soluble iron solution and continuously withdrawing a portion of the aqueous solution containing large size iron oxide crystals as product.
    Type: Grant
    Filed: June 23, 1978
    Date of Patent: May 6, 1980
    Assignee: Suntech, Inc.
    Inventor: Walter H. Seitzer
  • Patent number: 4201762
    Abstract: Transparent red iron oxide pigments of outstanding quality and particularly high clarity and strength and good dispersibility characteristics are described. The pigments are produced by heating a dry mixture of alpha-ferric oxide hydrate particles and at least 0.2 part per part of hydrate of a salt which is an alkali metal nitrate, nitrite or mixtures thereof to a temperature above the melting point of the salt and recovering the resulting ferric oxide as a pigment.
    Type: Grant
    Filed: November 6, 1978
    Date of Patent: May 6, 1980
    Assignee: Ciba-Geigy Corporation
    Inventor: James E. Daly
  • Patent number: 4178171
    Abstract: A process for the manufacture of acicular ferromagnetic iron particles by reducing acicular iron(III) oxide hydroxides which consist of pure synthetic lepidocrocite or a mixture of synthetic goethite and at least 70% by weight of synthetic lepidocrocite.The iron(III) oxide hydroxides used carry, on their surface, an alkaline earth metal cation and an anion of a monobasic, dibasic or tribasic aliphatic carboxylic acid of up to 6 carbon atoms or an organic compound containing at least two groups capable of chelating the alkaline earth metal cation, and are produced in such a way that they consist of at least 70 percent by weight of lepidocrocite and have a length-to-width ratio of not less than 15:1.Reduction of such iron(III) oxide hydroxides gives iron particles with pronounced shape anisotropy, which exhibit both good magnetic properties and a narrow field strength distribution.
    Type: Grant
    Filed: March 20, 1978
    Date of Patent: December 11, 1979
    Assignee: BASF Aktiengesellschaft
    Inventors: Werner Steck, Rudolf Brodt, Wilhelm Sarnecki, Helmut Jakusch, Manfred Ohlinger, Eberhard Koester
  • Patent number: 4174381
    Abstract: An improved industrial process and apparatus are provided for producing chlorine and iron oxide in a multi-stage recirculating-fluidized-bed reactor wherein ferric chloride in the vapor phase is reacted with an excess of oxygen at temperatures from 550.degree. to 800.degree. C. The improvement comprises utilizing a reactor that includes an initial "dense" zone and a downstream "dilute" zone. In the dense zone, a fuel is burned, reactants and recirculated iron oxide particles are heated, ferric chloride is vaporized and at least 50% of the ferric chloride is converted to chlorine and iron oxide. A solids volume fraction from 0.3 to 0.6 and a superficial gas velocity from 0.15 to 0.6 meters/second are maintained in the dense zone. In the downstream dilute zone, a solids fraction from 0.005 to 0.05 is maintained, along with a superficial gas velocity from 1.
    Type: Grant
    Filed: April 24, 1978
    Date of Patent: November 13, 1979
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventors: James W. Reeves, Robert W. Sylvester, David F. Wells
  • Patent number: 4153472
    Abstract: This invention describes the preparation of a red pigment of iron oxide from ferrous salts, by simultaneous reduction of organic nitro derivatives.
    Type: Grant
    Filed: December 13, 1977
    Date of Patent: May 8, 1979
    Assignee: Euteco S.p.A.
    Inventors: Tullio Pellizzon, Luigi Piccolo, Antonio Paolinelli
  • Patent number: 4145228
    Abstract: Aromatic amines and iron oxide pigment are produced by reacting a ferrous salt, a reduceable aromatic nitrogen compound chosen from nitroderivatives with a single nitro-group or with two nitro-groups and azoderivatives, and a basic compound, chosen from hydroxides and carbonates of ammonium, alkali metals and alkaline earth metals, operating at 25.degree.-200.degree. C. in an aqueous medium. The color of the pigment can be varied from yellow to black by increasing the reaction temperature and the molar ratio between ferrous salt and aromatic nitrogen compound.
    Type: Grant
    Filed: November 17, 1977
    Date of Patent: March 20, 1979
    Assignee: Euteco S.p.A.
    Inventors: Piero D. Croce, Tullio Pellizzon, Peter Schwarz, Luigi Piccolo
  • Patent number: 4145395
    Abstract: Particulate waste comprising hydrolyzable metal chlorides, typically chlorinated byproducts from the chlorination of titaniferous material, is treated in an oxidizing atmosphere at elevated temperature for depleting it of chlorine and for subsequent recovery of values.
    Type: Grant
    Filed: January 24, 1977
    Date of Patent: March 20, 1979
    Assignee: SCM Corporation
    Inventors: Steven J. Fitch, Philip R. Peeling
  • Patent number: 4145301
    Abstract: This invention relates to a process for the preparation of magnetic oxides and possibly of at least one other metal. It relates also to new products consisting in mono- and polymetal magnetic oxides.According to the invention a glycerin complex of iron and possibly at least one other metal is first prepared and the complex is decomposed into a mono- or polymetal magnetic oxide by hydrolysis or pyrolysis, the possibly decomposed glycerin complex being subjected to a thermal treatment, such as annealing or pyrolysis in an atmosphere of an inert gas, such as nitrogen.The invention relates to magnetic oxides containing 0.2 to 3% by weight of carbon, said oxides preferably containing cobalt and possibly a rare earth element such as yttrium or europium.
    Type: Grant
    Filed: November 1, 1976
    Date of Patent: March 20, 1979
    Assignee: Unibra Societe Anonyme
    Inventors: Philippe M. Bruylants, Jose J. Fripiat, Luc W. Rodrigue, Georges M. Poncelet, Antonin A. Munaut
  • Patent number: 4142915
    Abstract: This invention describes a process for preparing a yellow iron hydroxide pigment from inorganic ferrous salts and aromatic nitro compounds.
    Type: Grant
    Filed: November 1, 1977
    Date of Patent: March 6, 1979
    Assignee: EUTECO S.p.A.
    Inventors: Tullio Pellizzon, Luigi Piccolo, Antonio Paolinelli
  • Patent number: 4140746
    Abstract: The invention relates to the recovery of chlorine values from iron chloride by-produced from the chlorination of a titaniferous material containing more than 5% by weight iron oxide, and particularly from the carbo-chlorination of ilmenite, which, for example, can be the first stage in the so-called chloride route to form titanium dioxide pigment.The iron chloride which may be ferric chloride or ferrous chloride is subjected to a combination of reduction and oxidation reactions. In the reduction reaction, ferric chloride is dechlorinated to ferrous chloride by a reducing agent suitable for producing a chloride compound for recycle to the chlorination process or for sale and in the oxidation reaction ferrous chloride is oxidized to ferric oxide and ferric chloride, the ferric chloride being recycled to the reduction reaction.
    Type: Grant
    Filed: November 3, 1977
    Date of Patent: February 20, 1979
    Assignee: Mineral Process Licensing Corporation B.V.
    Inventors: John H. W. Turner, Charles E. E. Shackleton
  • Patent number: 4140539
    Abstract: An acicular to prismatic ferrimagnetic iron oxide pigment with a porosity of less than about 10% by volume, and optionally containing up to about 15% by weight of other metal oxides such as Zn or especially Co, are produced by heating a suspension of iron(III)oxide hydroxide in an autoclave to a temperature above about 100.degree. C in the presence of at least one mono-, di- or tri-saccharide, at least one alkali metal or alkaline earth metal hydroxide or carbonate and excess water, and washing, filtering and drying the resulting pigments.
    Type: Grant
    Filed: July 18, 1977
    Date of Patent: February 20, 1979
    Assignee: Bayer Aktiengesellschaft
    Inventors: Franz Hund, Gunter Buxbaum, Lutz Leitner, Ingo Pflugmacher
  • Patent number: 4139398
    Abstract: This invention describes a process for preparing a red iron oxide pigment from inorganic ferrous salts and aromatic nitro compounds.
    Type: Grant
    Filed: November 29, 1977
    Date of Patent: February 13, 1979
    Assignee: Euteco S.p.A.
    Inventors: Tullio Pellizzon, Luigi Piccolo, Peter Schwarz
  • Patent number: 4136158
    Abstract: In the production of acicular ferromagnetic iron oxide of highly uniform particle size by oxidizing an iron (II) hydroxide suspension at a pH of at least 11 with an oxygen-containing gas to form acicular iron (III) oxide hydroxide, reducing and optionally further reoxidizing this into ferromagnetic iron oxide, the improvement which comprises providing the iron (II) hydroxide suspension with a water-soluble silicate in an amount of less than 1.7% by atom based on the amount of the iron (II) hydroxide in the suspension and calculated as the ratio of Si to Fe (II) while prior to the oxidation of the suspension with the oxygen-containing gas.
    Type: Grant
    Filed: November 1, 1977
    Date of Patent: January 23, 1979
    Assignee: Toda Kogyo Corp.
    Inventors: Yosiro Okuda, Nanao Horiishi, Hiroshi Sumita, Tosiharu Harada
  • Patent number: 4133677
    Abstract: The process for producing acicular magnetic metallic particle powder with improved magnetic properties which include the characteristic steps for producing the acicular particles of metal oxide with homogeneous and dense coats of crystalline silica and to thereby protect the particles from heat-damages during the reduction thereof under high temperatures.
    Type: Grant
    Filed: March 31, 1977
    Date of Patent: January 9, 1979
    Assignee: Toda Kogyo Corp.
    Inventors: Goro Matsui, Koji Toda, Atushi Takedoi, Nanao Horiishi
  • Patent number: 4129454
    Abstract: An iron oxide based pigment in alpha-Fe.sub.2 O.sub.3 form, which contains the water insoluble part obtained by calcination of basic iron sulfate and/or jarosite based residues, this pigment being prepared by a process comprising calcining at a temperature from 600.degree. to 800.degree. C and during a period from 2 to 240 minutes basic iron sulfate and/or jarosite based residues, so as to decompose in an incomplete manner such basic iron sulfates and/or jarosite and to obtain in the calcined product an iron bonded sulfur content of more than 0.6%, and solubilizing the not decomposed iron sulfates with other soluble sulfated metals, such as zinc sulfate, by lixiviating the calcined product, these water-soluble compounds being then separated by appropriate processes.
    Type: Grant
    Filed: January 5, 1976
    Date of Patent: December 12, 1978
    Assignee: Societe de Prayon
    Inventor: Wilhelm E. Pavonet
  • Patent number: 4120941
    Abstract: Process of oxidizing halides, including mixtures thereof, with oxygen, oxygen-containing gases and/or oxygen-liberating substances in a combustion chamber, whereby the vapor pressure of the halides at introduction to the combustion or oxidation chamber is greater than the pressure within the combustion chamber. Recovery of halides at greater purity with substantial decrease of by-product deposits on operating equipment is realized.
    Type: Grant
    Filed: October 31, 1974
    Date of Patent: October 17, 1978
    Assignee: Halomet AG
    Inventors: Rudolf Nowak, Gerhard Holland
  • Patent number: 4112063
    Abstract: In the production of an FeOOH seed suspension, comprising contacting an iron(II) salt solution with a basic precipitant to form a basic iron(II) salt or hydroxide suspension, oxidizing the salt or hydroxide, the precipitation and oxidation steps being carried out locally separate from one another and recovering a suspension of FeOOH, the improvement which comprises(a) effecting the precipitation by mixing an about 1 to 20% by weight iron(II) salt solution with sufficient basic precipitant to precipitate about 25 to 95 atom % of the iron(II),(b) at another location oxidizing 10 to 50% of the iron(II) precipitated in (a) over a period of from about 0.5 to 5 hours at a temperature in the range from about 20.degree. C to 65.degree. C,(c) at another location oxidizing the suspension obtained in (b) with intensive mixing over a period of from about 0.
    Type: Grant
    Filed: December 3, 1976
    Date of Patent: September 5, 1978
    Assignee: Bayer Aktiengesellschaft
    Inventors: Gunter Buxbaum, Franz Hund
  • Patent number: 4107267
    Abstract: A process for regenerating waste acid, such as waste hydrochloric acid pickling liquor by producing aqueous hydrochloric acid of pickling concentration and generating iron oxide including that of pigment grade, comprises the steps of (1) concentrating the waste liquor, (2) reacting the concentrated liquor at a temperature below 1000.degree. F.
    Type: Grant
    Filed: July 8, 1977
    Date of Patent: August 15, 1978
    Assignee: Toledo Pickling & Steel Service, Inc.
    Inventor: Lars J. Hansen
  • Patent number: 4107009
    Abstract: A process for extracting copper from a copper bearing ore or concentrate which comprises immersing the ore or concentrate in an electrolyte, intimately mixing with the slurry so formed finely dispersed air or other oxygen-containing gas and maintaining the pH of the mixture at above 1.5 and below 7.0 throughout the process. Iron is solubilized in the process and precipitated as ferric oxide and the copper is taken into solution in which copper is primarily present as cuprous ions. The process is conducted at substantially atmospheric pressure and at temperatures of from 50.degree. C to the boiling point of the electrolyte. The electrolyte is acidic and contains chloride ions in a concentration between that sufficient to maintain in solution cuprous ions present and saturation.
    Type: Grant
    Filed: July 18, 1977
    Date of Patent: August 15, 1978
    Assignee: Dextec Metallurgical Proprietary Limited
    Inventor: Peter Kenneth Everett
  • Patent number: 4102951
    Abstract: A two-step process for the calcination of basic ferric sulphates in which the basic ferric sulphate is dehydrated by heating in a relatively low temperature range and the dehydrated product is then decomposed by heating in a relatively high temperature range.
    Type: Grant
    Filed: May 7, 1976
    Date of Patent: July 25, 1978
    Assignee: Monash University
    Inventor: Frank Lawson
  • Patent number: 4097574
    Abstract: Synthetic rutile is made from ilmenite by pre-oxidizing it, reducing it in a fluid bed, thereafter aeration leaching it, optionally acid leaching, and drying.
    Type: Grant
    Filed: June 16, 1976
    Date of Patent: June 27, 1978
    Assignee: United States Steel Corporation
    Inventors: Robert G. Auger, Edward F. Restelli, Jr.
  • Patent number: 4092407
    Abstract: Weighting material for a drilling fluid, e.g. a drilling mud, is produced by firing iron oxide solids, e.g. iron oxide ores, calcined pyritic ores or iron-oxide-containing products of other metallurgical processes, in a circulating fluidized bed or rotary furnace at a temperature of 1210.degree. C to 1400.degree. C in an oxidizing atmosphere in which the oxygen content is augmented to transform magnetitic components to oxides of lower magnetic susceptibility. The product is then cooled slowly at least until it reaches a temperature of 780.degree. C, also in an oxidizing atmosphere. The weighting materials have extremely low magnetic susceptibility and thus can be used without interfering with inductive monitoring of the position of the drill string.
    Type: Grant
    Filed: June 24, 1976
    Date of Patent: May 30, 1978
    Assignee: Metallgesellschaft Aktiengesellschaft
    Inventors: Hans-Joachim Rohrborn, Rainer Homann, Heribert Conrady, Dieter Menzel
  • Patent number: 4092401
    Abstract: Process for the recovery of pigment-grade iron oxide and technical hydrochloric acid of predetermined molarity, from iron chloride solutions such as pickling solutions containing hydrochloric acid. The iron chloride solution is concentrated until the molarity of the chloride ion therein is the same as the molarity of the hydrochloric acid which it is desired to produce. Concentrated sulfuric acid in slight stoichiometric excess relative to the iron, is then added to the iron chloride solution, which solution is thereafter evaporated to dryness. The distillation from this evaporation is hydrochloric acid of the predetermined molarity, and the dry residue is iron sulfate. The iron sulfate is calcined to drive off sulfur dioxide and sulfur trioxide and to leave iron oxide which may contain sulfates; and to remove these latter, the iron oxide is leached with dilute hydrochloric acid and is thereafter washed with water. The washed iron oxide is dried and micropulverized to produce a red iron oxide pigment.
    Type: Grant
    Filed: January 10, 1977
    Date of Patent: May 30, 1978
    Assignee: Compagnie Royale Asturienne des Mines
    Inventor: Noel Dreulle
  • Patent number: 4086321
    Abstract: A method and apparatus for producing pre metallic oxides by dissolving the metal or oxide in heated dilute hydrochloric acid to form metallic chloride in a water solution (which solution may instead, be a waste product from a steel strip pickling line), reacting said solution in a reactor in the presence of heated oxygen to form metal oxide, part of which oxide being carried over in vapor form to a variable throat venturi where it is redissolved and reintroduced into the reactor to insure that only low chloride oxide will be discharged as a product. The system operates under negative pressure to prevent leakage tendency of HCl to the outside atmosphere.
    Type: Grant
    Filed: June 21, 1976
    Date of Patent: April 25, 1978
    Assignee: Carl A. Holley
    Inventors: Carl A. Holley, Russell J. McKinnon
  • Patent number: 4075384
    Abstract: A magnetic recording tape of improved properties comprising a non-magnetic support and a two-layered magnetic coating composed of a ferromagnetic powder and a binder and formed on one surface of the support, wherein the lower magnetic layer has a coercive force of about 250 to about 300 Oe, a residual magnetic flux density of at least about 1,500 Gauss and a dry thickness of at least about 2.5 .mu.m, and the upper magnetic layer has a coercive force of about 350 to about 400 Oe, a residual magnetic flux density of not more than about 1,500 Gauss and a dry thickness of about 2.0 to 3.0 .mu.m, the ferromagnetic powder in the upper magnetic layer having an APP value of not more than 1.0.
    Type: Grant
    Filed: October 21, 1976
    Date of Patent: February 21, 1978
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Masaaki Suzuki, Akira Kasuga
  • Patent number: 4075313
    Abstract: A process for the production of hydrogen and oxygen from water comprising the steps of forming ferric chloride from ferriferrous oxide by reaction with a chloride ion yielding substance, thermally reducing the ferric chloride to produce ferrous chloride, reducing the ferrous chloride to metallic iron, then oxidizing the metallic iron with water so as to produce hydrogen. The metallic iron may be formed by reducing the ferrous compound with hydrogen. Two specific reactant regenerative closed cycle systems are disclosed utilizing the process of this invention for the production of hydrogen and oxygen.
    Type: Grant
    Filed: March 18, 1976
    Date of Patent: February 21, 1978
    Assignee: American Gas Association
    Inventors: Jon B. Pangborn, John C. Sharer, Robert H. Elkins
  • Patent number: 4075391
    Abstract: A process for preparing humidity-insensitive electrostatographic ferrite carrier materials comprising dry-blending ferrite-forming metal oxides, calcining the blended oxides to provide them with a saturation magnetic moment of about 6 to 30 electromagnetic units per gram, milling the calcined oxides in a slurry to reduce their particle size to about 0.8 to 1.6 microns while adding manganese oxide, copper oxide, and a sodium-free deflocculant to the slurry, pumping the milled slurry to holding/feeding tanks and adding a binder material to the slurry, spray-drying the slurry to form substantially spherical beads, screening the spray-dried beads, firing the screened beads in an ambient atmosphere at a temperature of up to about 2500.degree. F. for up to about 8 hours, deagglomerating the fired beads, and screening the beads to obtain ferrite carrier particles having controlled surface species and physical properties.
    Type: Grant
    Filed: October 29, 1975
    Date of Patent: February 21, 1978
    Assignee: Xerox Corporation
    Inventors: Allan C. Berg, John W. Fitzpatrick, Lewis O. Jones
  • Patent number: 4073874
    Abstract: In the recovery of chlorine from iron chloride by causing reaction between an oxidizing gas and a gas containing iron chloride as the predominant constituent within an oxidation furnace, the initial meeting of the two reacting gases is caused to take place in an unobstructed space within the furnace, the oxygen being injected into the furnace in directions and at a velocity such that the resulting turbulent flow due to the initial collision of the two gases will not reach the furnace wall, whereby depositing of Fe.sub.2 O.sub.3 on the furnace wall is reduced to a minimum.
    Type: Grant
    Filed: December 17, 1975
    Date of Patent: February 14, 1978
    Assignee: Mitsubishi Kinzoku K.K.
    Inventor: Seitaro Fukushima
  • Patent number: 4073878
    Abstract: Yellow hydrated ferric oxide having uniform and proper particle size can be economically produced by the present invention which comprises allowing an ammonium salt to be present in a given concentration in a ferrous salt solution, partially neutralizing the mixed solution with ammonia, oxidizing it with air to obtain a seed liquid, adding a ferrous salt solution to said seed liquid and simultaneously adding ammonia thereto to attain a suitable pH value and oxidizing the ferrous salt with air at said pH whereby a uniform particle size can be rapidly obtained.
    Type: Grant
    Filed: September 9, 1975
    Date of Patent: February 14, 1978
    Inventors: Tatsukiyo Otsuki, Sinya Takata
  • Patent number: 4066741
    Abstract: Hydrogen is produced by the thermal decomposition of water at temperatures of 1000.degree. C or below by making use of iron salts and carbon dioxide, which are circulated in closed circuits in the reaction system. The only raw material to be supplied from an external source is water; all intermediates are circulated in the reaction system. A nuclear reactor may be used as a heat source for the reaction.
    Type: Grant
    Filed: November 5, 1975
    Date of Patent: January 3, 1978
    Assignee: Japan Atomic Energy Research Institute
    Inventor: Shoichi Sato
  • Patent number: 4061726
    Abstract: Goethite is obtained by reacting an aqueous solution of an iron (II) salt with an aqueous solution of an alkali metal hydroxide and oxidizing the resulting iron(II) hydroxide. The oxidation is carried out in three stages. In the first stage, from 4 to 15% by weight are oxidized in the course of from 0.4 to 5 hours, in the second stage from 60 to 85% by weight are oxidized in the course of from 1.5 to 6 hours and in a third stage the remaining amount of iron is oxidized.
    Type: Grant
    Filed: October 15, 1976
    Date of Patent: December 6, 1977
    Assignee: BASF Aktiengesellschaft
    Inventors: Manfred Ohlinger, Eduard Schoenafinger, Guenter Vaeth, Heinz Stritzinger, Eberhard Koester, Hans Henning Schneehage, Werner Steck
  • Patent number: 4061725
    Abstract: Acicular gamma-iron(III) oxide is manufactured by reacting an iron(II) salt solution with an aqueous solution of an alkali metal hydroxide and oxidizing the resulting suspension of iron(II) hydroxide in three stages. In a first stage, at most from 0.1 to 4% by weight of the amount of iron(II) hydroxide originally present is oxidized in the course of from 0.1 to 4 hours, in a second stage from 10 to 25% by weight of the said original amount are oxidized in the course of from 1.5 to 6 hours and in a third stage the remaining amount is oxidized. After the oxidation, the goethite formed is reduced to magnetite and the latter is then oxidized to acicular gamma-iron(III) oxide.
    Type: Grant
    Filed: October 15, 1976
    Date of Patent: December 6, 1977
    Assignee: BASF Aktiengesellschaft
    Inventors: Manfred Ohlinger, Eduard Schoenafinger, Walter Schneider, Heinz Stritzinger, Guenter Vaeth
  • Patent number: 4061727
    Abstract: Acicular .gamma.-iron(III) oxide is manufactured by reacting an iron(II) salt solution with aqueous solutions of alkali metal hydroxides and oxidizing the resulting suspension of iron(II) hyroxides in 3 stages. In the first stage not more than 8 percent by weight of the iron(II) hydroxide originally present is oxidized over a period of 0.5 to 4 hours, in the second stage from 25 to 55 percent by weight over a period of 1.5 to 6 hours and the remainder thereof in a third stage. Following this oxidation, the goethite formed is reduced to magnetite, which is then oxidized to acicular .gamma.-iron(III) oxide.
    Type: Grant
    Filed: October 15, 1976
    Date of Patent: December 6, 1977
    Assignee: BASF Aktiengesellschaft
    Inventors: Guenter Vaeth, Manfred Ohlinger, Heinz Stritzinger, Eduard Schoenafinger, Eugen Wettstein, Wolfgang Guth
  • Patent number: 4060584
    Abstract: The dust produced in the chlorination of titaniferous ores comprises essentially particulate ferrous chloride plus solid contaminants including coke and various metal chlorides and oxides and is oxidized in successive stages at relatively low temperatures to recover particulate iron oxide and gaseous chlorine.
    Type: Grant
    Filed: February 14, 1977
    Date of Patent: November 29, 1977
    Assignee: Kronos Titan G.m.b.H.
    Inventors: Achim Hartmann, Achim Kulling, Hans Thumm
  • Patent number: 4060596
    Abstract: A method of making goethite powder in which a ferrous hydroxide suspension is stirred for about 3 hours in an inert atmosphere and then is oxidized to form goethite powder.
    Type: Grant
    Filed: October 31, 1975
    Date of Patent: November 29, 1977
    Assignee: Sony Corporation
    Inventor: Tokio Nakamura
  • Patent number: 4053578
    Abstract: A process for producing nickel oxide and other products in which percentages of metal powder, particularly nickel powder, and water are blended, the blend being subjected to a heat treatment to form the desired product. In the case of nickel oxide, the blend is exposed to air and temperature sufficient to form an oxide shell substantially about the powder particles, this treatment being followed by a final firing heat treatment.
    Type: Grant
    Filed: December 10, 1975
    Date of Patent: October 11, 1977
    Assignee: The International Nickel Company, Inc.
    Inventors: Brian Hill, William Herbert Elwood, Jr.