Patents Examined by Oscar R. Vertiz
  • Patent number: 4013783
    Abstract: A stable panchromatically sensitized zinc oxide having a low moisture sensitivity with dark discharge properties rendering it suitable as the photoconductive material of elements for indirect as well as direct electrophotography is produced by reacting finely divided zinc oxide with gaseous ammonia and carbon dioxide, while keeping the zinc oxide particles in motion, until a critical stage is reached corresponding usually to a weight increase of 4 to 7.5%, at which point the reacting is terminated and the product is heated to constant weight at a temperature between 190.degree. and 350.degree. C. Photoconductive elements made with the panchromatically sensitive zinc oxide not only are reusable indefinitely under varying atmospheric humidity conditions without loss of their sensitivity, but also exhibit a memory effect much lower than that of known photoconductive zinc oxides.
    Type: Grant
    Filed: April 30, 1975
    Date of Patent: March 22, 1977
    Assignee: Oce-van der Grinten N.V.
    Inventors: Jan A. de Putter, Johannes Kortenoeven
  • Patent number: 4013718
    Abstract: Urea is produced through an integrated, isobaric process in which raw ammonia synthesis gas, consisting essentially of H.sub.2, N.sub.2 and sufficient CO.sub.2 to produce the urea and compressed to a pressure slightly above the urea synthesis pressure, is decarbonated in a vertical film heat exchanger where it is contacted with a thin aqueous film containing NH.sub.3 with which the CO.sub.2 reacts to produce a concentrated carbamate solution that is withdrawn from the bottom of the exchanger and fed to a urea reactor. The compressed, unreacted synthesis gas containing traces of CO and saturated with NH.sub.3 is withdrawn from the upper part of the heat exchanger, NH.sub.3 is separated therefrom and recycled to the heat exchanger, and the balance of the unreacted synthesis gas is subjected to methanation to eliminate any CO and CO.sub.2 therein.
    Type: Grant
    Filed: March 20, 1974
    Date of Patent: March 22, 1977
    Assignee: Snam Progetti S.p.A.
    Inventors: Mario Guadalupi, Giorgia Pagani, Umberto Zardi, Ivo Paris
  • Patent number: 4012487
    Abstract: A stack gas, generally from a sulfuric acid plant, containing SO.sub.2, is contacted with an absorptive medium prepared by wetting at least the surface of a first metal selected from aluminum, magnesium and manganese with a second metal selected from mercury, indium, gallium and alloys of indium/gallium and contacting the wetted first metal with SO.sub.2, in a solvent medium in the presence of an excess of hydrogen ions until the first metal erodes and is taken up by the solution as a result of the reaction which takes place. The absorptive medium thus formed has the ability to absorb SO.sub.2 at lower temperatures and thereafter desorb SO.sub.2 at increased temperature and/or with inert gas stripping. The SO.sub.2 enriched gas stream obtained as a result of the desorption process can be recycled to the sulfuric acid plant.
    Type: Grant
    Filed: July 22, 1975
    Date of Patent: March 15, 1977
    Inventor: George G. Merkl
  • Patent number: 4012488
    Abstract: A catalyst chamber capable of converting the oxides of sulfur to hydrogen sulfide and the oxides of nitrogen to inert nitrogen and ammonia in the presence of a reducing atmosphere is inserted downstream of the boiler section of a fossil fuel burning power generator and there is added a system for extracting formed hydrogen sulfide from the fuel gas stream.After combustion of the primary fuel, typically sulfur bearing coal in excess air, a gaseous hydrocarbon such as methane, is combined with the products of combustion to at least scavenge the oxygen present to form a boiler effluent which ranges from slightly oxidizing to reducing in nature.Where the boiler effluent is reducing in nature, partial conversion of the oxides of sulfur and the oxides of nitrogen occur in the boiler, the balance occurring in the catalyst chamber.
    Type: Grant
    Filed: March 13, 1974
    Date of Patent: March 15, 1977
    Assignee: Ralph M. Parsons Company
    Inventor: Jack Brocoff
  • Patent number: 4012491
    Abstract: Phosphate values of high purity and concentration may be efficiently recovered from a wide range of phosphatic-mineral-containing materials including as-mined phosphate ore by leaching such ore with a dilute aqueous mixture of sulfuric and hydrochloric or nitric acid, and precipitating phosphate values as dicalcium phosphate. This product, which is already suitable for use in animal feed and agricultural fertilizer, can also be readily converted to the many other agricultural and industrial phosphate products without costly purification operations or means of control of pollution to the surrounding environment.
    Type: Grant
    Filed: October 25, 1974
    Date of Patent: March 15, 1977
    Assignee: United States Gypsum Company
    Inventor: Douglas Oliver Hauge
  • Patent number: 4012490
    Abstract: A system for separating, concentrating and storing radioactive krypton and xenon in the off-gases from a boiling water reactor, wherein adsorption and cryogenic distillation are both efficiently used for rapid and positive separation and removal of the radioactive noble gases, and for limiting such gases in circulation in the system to low inventory at all times, and wherein the system is self-regulating to eliminate operator options or attention.
    Type: Grant
    Filed: October 7, 1974
    Date of Patent: March 15, 1977
    Assignee: Airco, Inc.
    Inventor: Antony Lofredo
  • Patent number: 4012482
    Abstract: A process for scrubbing extracted ammonia from oximes. The process is particularly adaptable as a secondary scrub, prior to acid stripping, in a process in which metals are recovered from ammoniacal leach liquors by solvent extraction. The present process eliminates the pH rise of the aqueous scrub liquor associated with acid scrubbing of ammonia from oximes into which ammonia has been extracted. Extractable metal sulfates are utilized in an aqueous scrub solution at a pH <7. The net result is an exchange of ammonia on the oxime for copper or nickel in the scrub solution with resulting loading of copper or nickel by the oxime and the formation of ammonium sulfate in the aqueous scrub solution with no change in the pH of the aqueous scrub solution.
    Type: Grant
    Filed: July 21, 1975
    Date of Patent: March 15, 1977
    Assignee: Kennecott Copper Corporation
    Inventors: David L. Natwig, Roald R. Skarbo
  • Patent number: 4011302
    Abstract: A process for preparing low bulk density, highly absorbent, amorphous, hydrous, water-soluble alkali metal silicate particles having high internal porosity by spray drying a mixture of an aqueous sodium or potassium silicate solution and hydrogen peroxide.
    Type: Grant
    Filed: June 26, 1975
    Date of Patent: March 8, 1977
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Mohamed Defrawi
  • Patent number: 4011297
    Abstract: An improved liquid-liquid extraction process for separating metals from each other in which an aqueous solution containing metals is mixed with an organic solution containing an extraction agent that releases hydrogen ions. A mixture of aqueous dispersed phase and an organic continuous phase is formed and the pH of the aqueous dispersed phase is controlled by the addition of a neutralizing agent to the mixture of the aqueous dispersed phase and the organic continuous phase on the basis of pH measurements made with pH electrodes immersed in the mixture of the phases. These direct measurements permit accurate adaptation of the rate of addition of the neutralizing agent to the rate at which hydrogen ions are being released so that the pH of the aqueous dispersed phase is kept substantially constant. The phases are separated from each other after transfer of metal ions from the aqueous to the organic phase, and the separated metal values are recovered.
    Type: Grant
    Filed: April 1, 1975
    Date of Patent: March 8, 1977
    Assignee: Outokumpu Oy
    Inventors: Bror Goran Nyman, Raimo Juhani Leimala, Erik Gustav Back
  • Patent number: 4011300
    Abstract: Phosphoric acids having H.sub.2 0/P.sub.2 O.sub.5 mole ratios of about 4.5 or less are converted to aqueous solutions of ammonium polyphosphates of which at least about 40 percent of the P.sub.2 O.sub.5 is present as acyclic polyphosphates. The reaction is conducted at 500.degree. to about 750.degree. F. sufficient to increase the polymeric P.sub.2 O.sub.5 content at least 10 percent by reacting a highly dispersed, unconfined acid spray with substantially anhydrous ammonia. High conversions to polymeric species are obtained while minimizing both reactor fouling when using impure wet-process acids, and corrosion occurring with either wet-process or "white" acids.
    Type: Grant
    Filed: June 27, 1975
    Date of Patent: March 8, 1977
    Assignee: Union Oil Company of California
    Inventors: Bruce A. Harbolt, Donald C. Young
  • Patent number: 4011301
    Abstract: Ammonium phosphates are produced from wet-process phosphoric acids containing silicon and fluorine compounds by preconcentrating the acid and evolving some of the water, silicon and fluorine compounds as a vapor phase, maintaining it at a temperature above about 50.degree. C., neutralizing the liquid acid concentrate with ammonia, and absorbing the isolated vapor phase from the evaporation zone in a relatively cool, neutralized ammonium phosphate solution at a pH of at least about 5.5.
    Type: Grant
    Filed: October 23, 1975
    Date of Patent: March 8, 1977
    Assignee: Union Oil Company of California
    Inventor: Donald C. Young
  • Patent number: 4010238
    Abstract: A process for the selective removal of nitrogen oxides from waste gases containing nitrogen oxides, which comprises contacting the waste gases with a metal oxide catalyst having the following formula:V.sub.x A.sub.y O.sub.zwherein V is vanadium; A is at least one element selected from the group consisting of copper, zinc, tin, lead, titanium, phosphorus, chromium, iron, cobalt and nickel; x and y are each a numeral of 0.5 to 12; and z is a numeral of 1 to 60, at a temperature of 150.degree. to 800.degree. C in the presence of ammonia.
    Type: Grant
    Filed: March 19, 1974
    Date of Patent: March 1, 1977
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Tatsuo Shiraishi, Shinkichi Shimizu, Hiroshi Ichihashi, Tadashi Shindo
  • Patent number: 4010241
    Abstract: A process for the production of hydrogen fluoride, phosphoric anhydride, calcium polyphosphates and nitric acid, is disclosed, characterized in that natural phosphate is heated by a plasma stream of working gas in the presence of water vapors to form hydrogen fluoride which is recovered as a commercial product. Then the thus defluorinated phosphate is further heated by an air plasma stream having a bulk temperature of at least 3,500.degree. K. and containing nitrogen oxides. Under such conditions, the defluorinated phosphate decomposes to form phosphoric anhydride and calcium oxide.The gas stream carrying the phosphoric anhydride, the calcium oxide and the nitrogen oxides is cooled down to yield, as commercial products, either phosphoric anhydride and nitric acid, or calcium polyphosphates containing up to 70% P.sub.2 O.sub.5 and nitric acid, or else all of the three products, depending on the cooling conditions.
    Type: Grant
    Filed: August 27, 1974
    Date of Patent: March 1, 1977
    Inventors: Alfred Lvovich Mosse, Vladimir Vasilievich Pechkovsky, Anatoly Ivanovich Teterevkov, Igor Sergeevich Burov, Jury Nikolaevich Vilk, Vadim Andreevich Ershov, Alexandr Antonovich Chelnokov, Oleg Iosifovich Yasko, Vladimir Vladimirovich Bysjuk, Elena Dmitrievna Dzjuba
  • Patent number: 4010243
    Abstract: A process is provided for converting potassium chloride to potassium bicarbonate with desirable conversions which bicarbonate can then be calcined to potassium carbonate. In one embodiment the potassium bicarbonate is formed in a reaction medium which is an admixture of water and a water miscible alcohol with the other reactants employed being carbon dioxide and an alkylamine. In a more preferred embodiment an alcoholic solution of an alkylamine which solution is saturated with carbon dioxide will be prepared and then an aqueous solution of a potassium halide, preferably potassium chloride, will be added to the alcoholic solution so as to form potassium bicarbonate.
    Type: Grant
    Filed: November 28, 1975
    Date of Patent: March 1, 1977
    Assignee: Owens-Illinois, Inc.
    Inventor: Ian M. Thomas
  • Patent number: 4010246
    Abstract: Finely divided sulfur and an oxygen containing gas are combined and burnt. Finely divided sulfuric acid is introduced into the hot flame gases. The resulting gas containing SO.sub.2, water and oxygen can be processed to pure SO.sub.2.
    Type: Grant
    Filed: October 10, 1975
    Date of Patent: March 1, 1977
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Heinz Steinrotter, Karl Walderbach, Hansjorg Mathieu
  • Patent number: 4010237
    Abstract: A process for the extraction of nickel values from a nickel oxide/silicate ore having a high magnesia/low iron oxide content, e.g. 15-50% magnesia and 0-20% iron oxide by contacting the ore with an aqueous polyalkylenehexamine solution in the presence of oxygen. The general formula for the polyalkylenehexamine is NH.sub.2 (CH.sub.2).sub.n NH(CH.sub.2).sub.m NH(CH.sub.2).sub.n NH(CH.sub.2).sub.m NH(CH.sub.2).sub.n NH.sub.2 where n and m are 2 or 3, n and m being the same or different. Preferably n is 2 and m is 3.
    Type: Grant
    Filed: May 10, 1976
    Date of Patent: March 1, 1977
    Assignee: Du Pont of Canada Limited
    Inventor: David Alan Harbourne
  • Patent number: 4010245
    Abstract: In the production of hydrofluoric acid and calcium sulfate by subjecting sulfuric acid and fluorspar to a partial preliminary reaction in a preliminary reaction zone and the reaction is completed in an after-reaction zone at a temperature from about 100.degree. to 500.degree. C, the improvement which comprises effecting the preliminary reaction by circulating preliminary reaction product through said preliminary reaction zone, adding to the circulating preliminary reaction product at spaced locations in the preliminary reaction zone sulfuric acid preheated to a temperature of about 80.degree. to 200.degree. C and fluorspar preheated to a temperature of about 400.degree. to 800.degree. C, removing from said preliminary reaction zone gaseous hydrofluoric acid and a substantially dry mixture of calcium sulfate, unreacted sulfuric acid and fluorspar, and passing said dry mixture of calcium sulfate, unreacted sulfuric acid and fluorspar to said after-reaction zone.
    Type: Grant
    Filed: July 15, 1975
    Date of Patent: March 1, 1977
    Assignee: Bayer Aktiengesellschaft
    Inventors: Bernhard Spreckelmeyer, Hans Guth, Werner Schabacher, Hermann Rohe
  • Patent number: 4010240
    Abstract: Contaminated sulfuric acid which may contain water, organic compounds and inorganic salts is converted to almost pure concentrated sulfuric acid by passing the acid through a Pauling plant and distilling the concentrated contaminated acid.Addition of nitric acid improves the decomposition of organic compounds and ammonium salts of the contaminated acid.
    Type: Grant
    Filed: June 12, 1974
    Date of Patent: March 1, 1977
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Helmold von Plessen, Eberhard Fischer, Siegfried Schiessler
  • Patent number: 4010216
    Abstract: A novel codimerization process using a heterogeneous, nickel-containing catalysts comprisingA. a nickel carbonyl complex, andB. an acidic, solid, silica-based material are active in co-dimerization, of various olefins. In specific aspects, bis(triphenylphosphine) nickel dicarbonyl supported on an acidic, calcined, silica-alumina support containing a separate alumina phase, is active in, the codimerization of a conjugated diene and an alpha-olefin.
    Type: Grant
    Filed: April 14, 1975
    Date of Patent: March 1, 1977
    Assignee: Atlantic Richfield Company
    Inventor: Jin Sun Yoo
  • Patent number: 4010239
    Abstract: A highly sorbent iron oxide is prepared by reducing hematite to magnetite followed by a low temperature oxidation prior to contact with sulfur dioxide. The oxidized solids obtained in this manner are a more effective form of iron oxide sorbent for the oxides of sulfur.
    Type: Grant
    Filed: October 5, 1973
    Date of Patent: March 1, 1977
    Assignee: The Hanna Mining Company
    Inventor: Abraham A. Dor