Dissolving Or Leaching Of Iron Patents (Class 423/86)
  • Patent number: 4272343
    Abstract: A process for beneficiating ilmenite ore using electrolytic reduction. The ilmenite ore is admixed with an acidic solution to form a mixture. The mixture is electrolytically reduced to convert at least a portion of any ferric iron that is present to ferrous iron. The acidic solution dissolves the ferrous iron in the ilmenite ore and yields beneficiated ilmenite having a relatively high titanium dioxide content.
    Type: Grant
    Filed: January 9, 1980
    Date of Patent: June 9, 1981
    Assignee: Kerr-McGee Corporation
    Inventors: Dennis A. Brunsell, Olen L. Riggs, Jr.
  • Patent number: 4202863
    Abstract: In a process for recovering titanium metal values from a titanium bearing source which also contains iron, the source is subjected to a reductive roast followed by a leach of the reduced source with hydrogen chloride. The suppression of the dissolution of titanium during the leaching step of the process will be effected by the addition of a phosphoric acid to the leaching solution.
    Type: Grant
    Filed: November 27, 1978
    Date of Patent: May 13, 1980
    Assignee: UOP Inc.
    Inventor: William K. Tolley
  • Patent number: 4199552
    Abstract: An improved process for the production of synthetic rutile from ore containing titanium and iron, such as ilmenite ore, by a multi-step procedure employing controlled reduction, controlled oxidation and acid leaching. More specifically, the ilmenite ore first is reduced thermally such that substantially all of the iron (III) present has been converted to iron (II) and some metallic iron. The reduced ore then is oxidized with an oxidizing gas substantially free of elemental oxygen to convert the metallic iron to iron (II) without the substantial formation of iron (III). The oxidized ore then is leached to remove the iron (II) and calcined to produce synthetic rutile. The synthetic rutile so produced contains in excess of 92 percent titanium dioxide and less than 2 percent iron (III), by weight. Often, the synthetic rutile contains less than 1 percent total iron by weight.
    Type: Grant
    Filed: May 26, 1978
    Date of Patent: April 22, 1980
    Assignee: Kerr-McGee Corporation
    Inventor: Theodore A. Rado
  • Patent number: 4197276
    Abstract: Titanium metal values may be recovered from iron and titanium bearing sources such as an ilmenite ore by subjecting the source to a reductive roast after having crushed the source to a desired particle size. The reduced source is then leached by treatment with a halogen-containing compound to form soluble titanium halides and iron halides. Thereafter, the soluble titanium halide is precipitated as titanium dioxide by treatment with an iron oxide such as ferric oxide. The desired titanium dioxide or rutile may be recovered without an appreciable loss by effecting the leach step of the process in such a manner so that the solution potential is not greater than about +150 millivolts.
    Type: Grant
    Filed: July 31, 1978
    Date of Patent: April 8, 1980
    Assignee: UOP Inc.
    Inventors: William K. Tolley, John C. Stauter
  • Patent number: 4178176
    Abstract: Iron metal values and titanium metal values may be recovered from iron and titanium bearing sources such as ilmenite by subjecting the source to a reductive roast followed by leaching of the reduced source with a halogen-containing compound. Thereafter, the iron halide is crystallized and separated from the soluble titanium halides. One portion of the iron halides is subjected to a reducing step to form metallic iron while a second portion is oxidized, the iron oxides being used to precipitate the titanium as titanium dioxide. The titanium dioxide may then be separated and recovered while the liquid portion is recycled to the leaching zone.
    Type: Grant
    Filed: July 19, 1978
    Date of Patent: December 11, 1979
    Assignee: UOP Inc.
    Inventor: William K. Tolley
  • Patent number: 4175952
    Abstract: Iron metal values and titanium metal values may be recovered from iron and titanium bearing sources such as an ilmenite ore by subjecting the source to a reductive roast after crushing the source to a desired particle size. The reduced source is then leached by treatment with a halogen-containing compound to form soluble titanium halides and iron halides. Thereafter the soluble titanium halide is precipitated by treatment with iron oxides such as ferric oxide and after separation from the soluble iron halides is recovered as titanium dioxide. The soluble iron halides are then crystallized by reducing the temperature of the solution and one portion of the crystals are subjected to a reduction step to form metallic iron. The other portion of the iron halide crystals is oxidized to form ferric oxide which is used to precipitate the titanium compound.
    Type: Grant
    Filed: July 19, 1978
    Date of Patent: November 27, 1979
    Assignee: UOP Inc.
    Inventor: William K. Tolley
  • Patent number: 4174963
    Abstract: Titanium metal values may be recovered from titanium and iron bearing sources such as an ilmenite ore by subjecting the source to an oxidation treatment and a reductive roast after having crushed the source to a desired particle size. The reduced source is then leached by treatment with a halogen-containing compound to form soluble titanium halides and iron halides. Thereafter the soluble titanium halide is precipitated as titanium dioxide by treatment with an iron oxide such as ferric oxide and recovered. The amount of titanium dioxide which is recovered is determined by the amount of reductant utilized in the reductive roast.
    Type: Grant
    Filed: July 31, 1978
    Date of Patent: November 20, 1979
    Assignee: UOP Inc.
    Inventor: William K. Tolley
  • Patent number: 4172878
    Abstract: Titanium metal values may be recovered from a titanium bearing source such as an ilmenite ore by subjecting the source to a reductive roast, leaching the reduced source with a halogen-containing compound followed by crystallization of the iron halide impurity which is separated from the soluble titanium halide. The soluble titanium halide is then treated with an iron oxide to form titanium dioxide. The yield of titanium dioxide may be greatly improved by effecting the nucleation of the titanium in a manner which comprises adding the iron oxide to the solution without agitation. Upon completion of the nucleation reaction, the solids are then thoroughly dispersed before removing the solid titanium dioxide.
    Type: Grant
    Filed: July 21, 1978
    Date of Patent: October 30, 1979
    Assignee: UOP Inc.
    Inventor: William K. Tolley
  • Patent number: 4158041
    Abstract: This invention relates to a process for separating rutile and ilmenite from ilmenite leach tails and is effected by treating the leach tails from an acidic leach to a flotation step whereby gangue is separated from the unreacted ilmenite and rutile. The latter is then roasted at an elevated temperature in a hydrous atmosphere to convert the ilmenite to a magnetic material. Thereafter the ilmenite may then be subjected to a magnetic separation whereby non-magnetic rutile may be recovered while the magnetic portion is recycled for further separation.
    Type: Grant
    Filed: February 21, 1978
    Date of Patent: June 12, 1979
    Assignee: UOP Inc.
    Inventor: William K. Tolley
  • Patent number: 4107264
    Abstract: An improved process is described for recovering TiO.sub.2, useful as a white pigment, from ilmenite-type ores, including the steps of digesting the ore with aqueous hydrofluroic acid, separating out iron impurities from the resulting solution, precipitating hydrated titanium dioxide from the iron-free solution with ammonium hydroxide, and calcining the precipitate to obtain pigmentary TiO.sub.2, wherein the improvement comprises subjecting aqueous solutions of by-product ammonium fluoride, formed in the process, to electrodialytic water-splitting to form an aqueous solution of ammonium hydroxide and an aqueous solution of hydrogen fluoride and recycling said aqueous ammonium hydroxide to the precipitation step and said aqueous hydrogen fluoride to the digestion step.
    Type: Grant
    Filed: November 14, 1977
    Date of Patent: August 15, 1978
    Assignee: Allied Chemical Corporation
    Inventors: Krishnamurthy Nagasubramanian, Kang-Jen Liu
  • 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: 4089675
    Abstract: A process is disclosed which removes iron from ilmenite ore thereby rendering it suitable for use in the chlorination process for forming TiO.sub.2 from titanium ores. One advantage of the disclosed process is that the iron is removed from the ilmenite by a method which performs a reduction step in the sulfuric acid process for producing TiO.sub.2 from titanium ore.
    Type: Grant
    Filed: October 5, 1976
    Date of Patent: May 16, 1978
    Assignee: American Cyanamid Company
    Inventors: Peter Joseph Preston, George Leathwhite Roberts, Jr., Dennis Arthur Filimore, Gerard Martin Sheehan
  • Patent number: 4085190
    Abstract: A catalytic ilmenite reduction procedure is described which provides a magnetic fraction consisting of the iron and titanium values of the ilmenite ores and a non-magnetic gangue. The magnetic fraction, after solubilization of the reduced iron, provides beneficiated Rutile-type titania product with purity ranges from 80 to 95% depending on the grade of ilmenite starting material. The titanias are further purified by sulfation and a metathetical reaction to convert the titanyl sulfates to chlorides by CaCl.sub.2.
    Type: Grant
    Filed: April 29, 1975
    Date of Patent: April 18, 1978
    Inventor: Chyn Duog Shiah
  • Patent number: 4058393
    Abstract: The invention relates to the beneficiation of both natural and artificial titaniferous ores, specifically ilmenites by adding to the ores a fluoride, preferably a normally insoluble fluoride in an amount such that the percentage of fluorine ion relative to the titania values lies between 13% and 50%, adding to the mixture hydrochloric acid, the fluorine ions acting as an activating agent. After dissolution, the titanium is precipitated out, as a mixture of titanium dioxide, titanium oxy hydroxy fluoride and titanium oxy fluoride, the iron values largely remaining in solution.
    Type: Grant
    Filed: June 23, 1975
    Date of Patent: November 15, 1977
    Assignee: The University of Melbourne
    Inventor: Robert Joseph William McLaughlin
  • Patent number: 4038364
    Abstract: In the production of synthetic rutile from a titanium and iron-containing ore by reducing most of the iron(III) in said ore into iron(II) with a steam-containing gaseous reducing agent at a temperature of about 850.degree. to 1100.degree. C, followed by leaching to remove the iron(II) and iron(III) and drying of the residue, the improvement which comprises using as said reducing agent a gas containing hydrogen and steam and optionally at least one of CO and CO.sub.2 wherein the H.sub.2 + CO : H.sub.2 O + CO.sub.2 molar ratio of the reducing agent is between 0.36 and 1.8. The reducing agent may comprise a mixture of hydrogen and steam or it may be the partial combustion product of a hydrocarbon. Advantageously, the ore is oxidized at 550.degree. to 1200.degree. C prior to reduction. The reduction permits ready dissolution of the iron during leaching without risk of hydrogen evolution.
    Type: Grant
    Filed: December 30, 1974
    Date of Patent: July 26, 1977
    Assignee: Bayer Aktiengesellschaft
    Inventor: Gunter Lailach
  • Patent number: 4038363
    Abstract: Upgrading of titanium values in a slag such as Sorelslag by working up the lag such as by alkali salt roasting to render the slag leachable in a plurality of leaching stages to recover titania (and other) values of 94 to 97 percent purity useful in a sulphate or a chloride process for producing titanium dioxide.
    Type: Grant
    Filed: October 21, 1975
    Date of Patent: July 26, 1977
    Assignee: Quebec Iron & Titanium Corporation-Fer et Titane due Quebec, Inc.
    Inventor: Basil Jarish
  • Patent number: 4019898
    Abstract: A small amount of sulfate ion is added to the hydrochloric acid leach liquor used to beneficiate ilmenite ore whereby fines or slime formation in the mother liquor is minimized or reduced and the color of the solid beneficiated ilmenite product is lighter.
    Type: Grant
    Filed: April 30, 1976
    Date of Patent: April 26, 1977
    Assignee: Benilite Corporation of America
    Inventors: James H. Chen, Lewis W. Huntoon
  • Patent number: 3959465
    Abstract: Titanium minerals are concentrated by leaching with an acid leaching agent in the presence of a chelating agent, sulfonate surfactant or polyacrylamide surfactant, wherein the iron components are removed from the minerals.
    Type: Grant
    Filed: May 24, 1974
    Date of Patent: May 25, 1976
    Assignee: Mitsubishi Chemical Industries Ltd.
    Inventors: Tokuzo Kurata, Satoshi Emi, Kunihiko Ofuchi, Tsutomu Takeuchi, Isamu Sone