Patents Examined by Oscar R. Vertiz
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Patent number: 4013783Abstract: 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: GrantFiled: April 30, 1975Date of Patent: March 22, 1977Assignee: Oce-van der Grinten N.V.Inventors: Jan A. de Putter, Johannes Kortenoeven
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Patent number: 4013718Abstract: 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aqueous film containing NH.sub.3 with which the CO.sub.2 reacts to produce a concentrated carbamate solution that is withdrawn from the bottom of the exchanger and fed to a urea reactor. The compressed, unreacted synthesis gas containing traces of CO and saturated with NH.sub.3 is withdrawn from the upper part of the heat exchanger, NH.sub.3 is separated therefrom and recycled to the heat exchanger, and the balance of the unreacted synthesis gas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: GrantFiled: March 20, 1974Date of Patent: March 22, 1977Assignee: Snam Progetti S.p.A.Inventors: Mario Guadalupi, Giorgia Pagani, Umberto Zardi, Ivo Paris
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Patent number: 4012487Abstract: 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: GrantFiled: July 22, 1975Date of Patent: March 15, 1977Inventor: George G. Merkl
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Patent number: 4012488Abstract: 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: GrantFiled: March 13, 1974Date of Patent: March 15, 1977Assignee: Ralph M. Parsons CompanyInventor: Jack Brocoff
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Patent number: 4012491Abstract: 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: GrantFiled: October 25, 1974Date of Patent: March 15, 1977Assignee: United States Gypsum CompanyInventor: Douglas Oliver Hauge
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Patent number: 4012490Abstract: 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: GrantFiled: October 7, 1974Date of Patent: March 15, 1977Assignee: Airco, Inc.Inventor: Antony Lofredo
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Patent number: 4012482Abstract: 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: GrantFiled: July 21, 1975Date of Patent: March 15, 1977Assignee: Kennecott Copper CorporationInventors: David L. Natwig, Roald R. Skarbo
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Patent number: 4011302Abstract: 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: GrantFiled: June 26, 1975Date of Patent: March 8, 1977Assignee: E. I. Du Pont de Nemours and CompanyInventor: Mohamed Defrawi
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Patent number: 4011297Abstract: 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: GrantFiled: April 1, 1975Date of Patent: March 8, 1977Assignee: Outokumpu OyInventors: Bror Goran Nyman, Raimo Juhani Leimala, Erik Gustav Back
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Patent number: 4011300Abstract: 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: GrantFiled: June 27, 1975Date of Patent: March 8, 1977Assignee: Union Oil Company of CaliforniaInventors: Bruce A. Harbolt, Donald C. Young
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Patent number: 4011301Abstract: 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: GrantFiled: October 23, 1975Date of Patent: March 8, 1977Assignee: Union Oil Company of CaliforniaInventor: Donald C. Young
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Patent number: 4010238Abstract: 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: GrantFiled: March 19, 1974Date of Patent: March 1, 1977Assignee: Sumitomo Chemical Company, LimitedInventors: Tatsuo Shiraishi, Shinkichi Shimizu, Hiroshi Ichihashi, Tadashi Shindo
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Patent number: 4010241Abstract: 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: GrantFiled: August 27, 1974Date of Patent: March 1, 1977Inventors: 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
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Patent number: 4010243Abstract: 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: GrantFiled: November 28, 1975Date of Patent: March 1, 1977Assignee: Owens-Illinois, Inc.Inventor: Ian M. Thomas
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Patent number: 4010246Abstract: 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: GrantFiled: October 10, 1975Date of Patent: March 1, 1977Assignee: Hoechst AktiengesellschaftInventors: Heinz Steinrotter, Karl Walderbach, Hansjorg Mathieu
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Patent number: 4010237Abstract: 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: GrantFiled: May 10, 1976Date of Patent: March 1, 1977Assignee: Du Pont of Canada LimitedInventor: David Alan Harbourne
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Patent number: 4010245Abstract: 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: GrantFiled: July 15, 1975Date of Patent: March 1, 1977Assignee: Bayer AktiengesellschaftInventors: Bernhard Spreckelmeyer, Hans Guth, Werner Schabacher, Hermann Rohe
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Patent number: 4010240Abstract: 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: GrantFiled: June 12, 1974Date of Patent: March 1, 1977Assignee: Hoechst AktiengesellschaftInventors: Helmold von Plessen, Eberhard Fischer, Siegfried Schiessler
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Patent number: 4010216Abstract: 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: GrantFiled: April 14, 1975Date of Patent: March 1, 1977Assignee: Atlantic Richfield CompanyInventor: Jin Sun Yoo
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Patent number: 4010239Abstract: 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: GrantFiled: October 5, 1973Date of Patent: March 1, 1977Assignee: The Hanna Mining CompanyInventor: Abraham A. Dor