With Control Of Oxygen Content In Oxidation Gas Patents (Class 502/52)
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Patent number: 5560817Abstract: Hydrocarbon fluid catalytic cracking (FCC) plants are debottlenecked by replacing air feed to the cracking catalyst regenerator with oxygen and carbon dioxide exhaust from the catalyst regenerator and removing methane and hydrogen from the wet gas stream leaving the main fractionator overhead receiver prior to its introduction into a wet gas compressor system. Nitrogen is removed from the exhaust gas and methane and hydrogen are removed from the wet gas in the same pressure swing adsorption (PSA) plant. During air replacement, exhaust gas is processed in the PSA plant and when the desired amount of nitrogen is removed from the exhaust gas, feed of exhaust gas to the PSA plant is terminated and flow of wet gas to the PSA plant is initiated.Type: GrantFiled: September 30, 1994Date of Patent: October 1, 1996Assignee: The BOC Group, Inc.Inventors: Raghu K. Menon, Ramakrishnan Ramachandran
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Patent number: 5521134Abstract: A method of regenerating V/P/O oxidation catalyst used for the partial oxidation of n-butane which comprises terminating the n-butane feed and contacting the catalyst with an oxygen containing gas, such as air for a sufficient period of time to regenerate the catalyst such that when the n-butane feed is restarted the yield is greater than just before the treatment.Type: GrantFiled: July 25, 1995Date of Patent: May 28, 1996Assignee: Scientific Design Company, Inc.Inventors: Arie Bortinger, Michael Bruscino
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Patent number: 5446000Abstract: A method of removing chloride from phosphorus/vanadium/oxygen mixed oxide oxidation catalysts comprising treating a chloride containing catalyst comprising phosphorus, vanadium and oxygen with a stream of gas comprising oxygen, steam and an inert gas at flow rate and temperature and for a period of time to substantially reduce the amount of chloride in the catalyst.Type: GrantFiled: March 14, 1994Date of Patent: August 29, 1995Assignee: Scientific Design Company, Inc.Inventor: Arie Bortinger
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Patent number: 5393717Abstract: There is provided a process for regenerating a coked catalyst comprising a zeolite and a noble metal such as platinum. The process involves treating the coked catalyst under somewhat mild oxidation conditions, whereby a sufficient portion of the coke is removed from the catalyst to restore the hydrocarbon sorption properties of the zeolite component to the level observed in the non-coked form. Surprisingly, the original activity of the catalyst is substantially restored, even though a substantial amount of coke remains on the regenerated catalyst.Type: GrantFiled: May 18, 1993Date of Patent: February 28, 1995Assignee: Mobil Oil Corp.Inventors: Minas R. Apelian, Anthony S. Fung, George H. Hatzikos, Clinton R. Kennedy, Chung-Hur Lee, Thomas R. Kiliany, Poh K. Ng, David A. Pappal
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Patent number: 5376607Abstract: A semi-continuous process for combusting coke from catalyst particles in a fixed bed is improved by rejecting from the combustion process a high moisture content flue gas stream which is produced by the combustion of a relatively large proportion of the hydrogen in the coke that enters the combustion section during an early stage of combustion. By operating the early stage of combustion at conditions to increase the rate of combustion of the hydrogen in the coke relative to that of the carbon in the coke, the overall equilibrium level of water in a flue gas/recycle gas that circulates through the process is lowered. The high moisture content flue gas stream from the early stage of combustion is rejected separately from the process.Type: GrantFiled: February 11, 1993Date of Patent: December 27, 1994Assignee: UOPInventor: Paul A. Sechrist
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Patent number: 5365009Abstract: An alkylation process which utilizes a solid alkylation catalyst is disclosed. The catalyst, which has carbonaceous material adsorbed thereto, is regenerated by reacting the adsorbed carbonaceous material. The reaction step is accomplished by heating the catalyst in the presence of ozone to form an ozonated hydrocarbon, wherein the ozonated hydrocarbon includes carbonyl carbons. The ozonated hydrocarbon is removed by desorbing the carbonyl carbons from the solid alkylation catalyst. The carbonaceous material is preferably reacted at a temperature ranging from about 20.degree. C. to 200.degree. C. The ozone is preferably in a gaseous stream at a concentration ranging from about 1 to 50 volume percent. The carbonyl components are preferably desorbed from the heated alkylation catalyst by sweeping the catalyst with a desorption fluid.Type: GrantFiled: April 14, 1993Date of Patent: November 15, 1994Assignee: Exxon Research and Engineering CompanyInventors: Ashok Uppal, William J. Murphy, Joseph P. Boyle
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Patent number: 5362694Abstract: A process for regeneration of spent sulfated and calcined solid superacid catalyst is disclosed. Said process comprises heating said catalyst to a temperature of approximately 450.degree. C. and contacting said catalyst with a gas stream comprising oxygen or air and sulfur dioxide. This regeneration process can be performed in situ.Type: GrantFiled: March 30, 1993Date of Patent: November 8, 1994Assignee: Sun Company, Inc. (R&M)Inventors: Elmer J. Hollstein, Chao-Yang Hsu
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Patent number: 5348921Abstract: The regeneration of sulfur sorbents having sulfate forming tendencies and used for desulfurizing hot product gas streams such as provided by coal gasification is provided by employing a two-stage regeneration method. Air containing a sub-stoichiometric quantity of oxygen is used in the first stage for substantially fully regenerating the sorbent without sulfate formation and then regeneration of the resulting partially regenerated sorbent is completed in the second stage with air containing a quantity of oxygen slightly greater than the stoichiometric amount adequate to essentially fully regenerate the sorbent. Sulfate formation occurs in only the second stage with the extent of sulfate formation being limited only to the portion of the sulfur species contained by the sorbent after substantially all of the sulfur species have been removed therefrom in the first stage.Type: GrantFiled: June 14, 1993Date of Patent: September 20, 1994Assignee: The United States of America as represented by the United States Department of EnergyInventors: Larry A. Bissett, Larry D. Strickland, John M. Rockey
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Patent number: 5306682Abstract: A crystalline silicate catalyst having deposited coke thereon is regenerated by being contacted with an oxygen-containing gas having a moisture content of 0.2% by volume or less at a temperature of 400.degree.-600.degree. C.Type: GrantFiled: December 21, 1992Date of Patent: April 26, 1994Assignee: Research Association for the Utilization of Light OilInventors: Masaaki Ueda, Teruo Murakami, Shunji Shibata, Kazuo Hirabayashi, Tadami Kondoh, Kohji Adachi, Nobuko Hoshino, Shinichi Inoue
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Patent number: 5254516Abstract: Highly durable and chemically reactive zinc titanate materials are prepared in a particle size range of 50 to 400 .mu.m suitable for a fluidized-bed reactor for removing reduced sulfur species in a gaseous form by granulating a mixture of fine zinc oxide and titanium oxide with inorganic and organic binders and by optional additions of small amounts of activators such as CoO and MoO.sub.3 ; and then indurating it at 800.degree. to 900.degree. C. for a time sufficient to produce attrition-resistant granules.Type: GrantFiled: March 26, 1992Date of Patent: October 19, 1993Assignee: Research Triangle InstituteInventors: Raghubir P. Gupta, Santosh K. Gangwal, Suresh C. Jain
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Patent number: 5254512Abstract: A method for continuously treating a gas using an apparatus with a catalyst bed housed therein comprises the steps of passing a subject gas through the catalyst bed to adsorb the adsorbable substances in the subject gas thereto; and passing a regenerating gas through the catalyst bed adsorbed by the adsorbable substances in the subject gas to react and decompose them and simultaneously regenerate the catalyst bed. A particular apparatus is used with this method.By carrying out this method of the present invention using the gas treating apparatus, it is possible to continuously, efficiently and economically advantageously treat a gas containing a malodorous component, harmful component, organic solvent, hydrocarbon vapor or the like.Type: GrantFiled: November 22, 1991Date of Patent: October 19, 1993Assignee: Sumitomo Seika Chemicals Co., Ltd.Inventors: Kanji Ueda, Yoshinori Takata, Tadaichi Shibahara, Yoshinori Yoshida
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Patent number: 5235121Abstract: The present invention provides a method and apparatus for reforming a hydrocarbon feedstock in the presence of steam using a steam-active reforming catalyst The present invention can generally be used in conjunction with any steam-active reforming processes wherein the hydrocarbon reforming and catalyst regeneration operations are conducted simultaneously and the catalyst is regenerated using a steam-diluted oxygen (or air) regeneration medium. In the present invention, catalyst regeneration effluent gas is advantageously reused in the reforming operation to provide at least a portion of the steam environment required for reforming the hydrocarbon feedstock. Free oxygen is preferably removed from the regeneration effluent gas before the regeneration effluent gas is brought into contact with the hydrocarbon feedstock.Type: GrantFiled: August 2, 1991Date of Patent: August 10, 1993Assignee: Phillips Petroleum CompanyInventors: Francis M. Brinkmeyer, Warren M. Ewert, Homer M. Fox, D. F. Rohr, Jr.
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Patent number: 5227566Abstract: A process for the dehydrogenation of a hydrocarbon selected from the group consisting of propane and butane in the presence of a catalyst comprising platinum and a carrier material. Reconditioning of catalyst particles containing platinum by transferring the catalyst particles through a combustion zone, a drying zone and a re-dispersion zone improves the process. Drying of the catalyst particles immediately after the combustion of coke improves the operation of a platinum re-dispersion zone. The lower moisture content in the re-dispersion zone allows the equilibrium reaction between hydrogen chloride and oxygen on the one hand, and water and chlorine on the other hand to be shifted to the production of chlorine. This shift of the equilibrium reaction can be further improved by maintaining an oxygen-enriched environment within the platinum re-dispersion zone. The use of a much lower chloride concentration in the re-dispersion zone reduces the emissions of hydrogen chloride from the regeneration zone.Type: GrantFiled: October 21, 1991Date of Patent: July 13, 1993Assignee: UOPInventors: Paul R. Cottrell, Michael E. Fettis
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Patent number: 5206194Abstract: A reactivated catalyst having optimum activity for hydrocracking and other acid catalyzed chemical conversion processes is prepared by contacting its deactivated counterpart, which contains a crystalline molecular sieve, a Group VIII noble metal hydrogenation component and carbonaceous deposits, with a gas containing molecular oxygen, preferably air, at a temperature between 950.degree. and 1200.degree. F., preferably between about 1050.degree. and 1150.degree. F., for a time sufficient to remove at least a portion of the carbonaceous deposits. When the reactivated catalyst contains a dealuminated Y zeolite that has been ion-exchanged with both noble metal and rare earth metal cations, its activity for hydrocracking in an ammonia-deficient atmosphere can be further increased by a rejuvenation procedure in which the reactivated catalyst is contacted with an aqueous ammonia solution in which an ammonium salt has been dissolved.Type: GrantFiled: June 20, 1991Date of Patent: April 27, 1993Assignee: Union Oil Company of AmericaInventor: Danford E. Clark
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Patent number: 5183789Abstract: A process for the regeneration of a coked platinum, or polymetallic platinum reforming catalyst with ozone. The coked catalyst is contacted, and carbon burned from the catalyst at temperatures ranging from about 20.degree. C. to 200.degree. C., preferably about 60.degree. C. to 150.degree. C., with a gaseous stream containing ozone in concentration ranging from about 1 to 50 volume percent ozone sufficient to substantially deplete said catalyst of sufficient carbon to restore the activity of the catalyst to that of the corresponding fresh catalyst.Type: GrantFiled: March 11, 1991Date of Patent: February 2, 1993Assignee: Exxon Research and Engineering CompanyInventor: Joseph P. Boyle
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Patent number: 5180700Abstract: The useful life of the palladium dehydrogenation catalyst used in the preparation of 2-alkylpyrimidines from 1,3-diaminopropane and an appropriate alkanecarboxylic acid in a continuous vapor phase process is substantially increased by employing a stoichiometric excess of the carboxylic acid and by using catalyst pellets of less than 3-4 mm diameters. Additionally, the dehydrogenation catalyst can be regenerated in situ by controlled air oxidation below 350.degree. C.Type: GrantFiled: May 13, 1991Date of Patent: January 19, 1993Assignee: DowElancoInventors: Eva F. Tai, John W. Hull, Jr., Kenneth E. First
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Patent number: 5162274Abstract: Whetlerite degraded by exposure to atmospheric contaminants is treated to restore its ability to adsorb toxic air pollutants by passing through it a flow of an oxygen-containing gas further containing from 500 to 2000 ppm of carbon monoxide and water vapor corresponding to 60 to 90 percent relative humidity at 60 to 80 degrees C.Type: GrantFiled: December 13, 1990Date of Patent: November 10, 1992Assignee: The United States of America as represented by the Secretary of the NavyInventor: Victor R. Deitz
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Patent number: 5155075Abstract: A process for regenerating a coke contaminated reforming catalyst comprising platinum on a molecular sieve, said process consisting essentially of contacting said catalyst with a halogen-free oxygen-containing gas at a temperature of less than 780.degree. F. for a sufficient period of time such that the aromatization activity is restored to within 20.degree. F. of the activity said catalyst possessed at the start of the previous run cycle.Type: GrantFiled: March 1, 1991Date of Patent: October 13, 1992Assignee: Chevron Research and Technology CompanyInventors: Robert A. Innes, Dennis L. Holtermann, Bernard F. Mulaskey
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Patent number: 5145815Abstract: Methods are provided for regenerating a zeolitic molecular sieve having a sulfur-containing carbonaceous material deposited thereon by contacting the zeolitic molecular sieve with an oxygen-containing regeneration feed gas to remove at least a portion of the carbonaceous deposit material and thereafter absorbing sulfur oxides present in the regeneration gas using soda-lime absorbent. The methods can inhibit the deactivation of zeolitic molecular sieves by avoiding contact thereof with the sulfur oxides.Type: GrantFiled: August 19, 1991Date of Patent: September 8, 1992Assignee: UOPInventor: Andrew S. Zarchy
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Patent number: 5087792Abstract: A process for the dehydrogenation of a hydrocarbon selected from the group consisting of propane and butane in the presence of a catalyst comprising platinum and a carrier material. Reconditioning of catalyst particles containing platinum by transferring the catalyst particles through a combustion zone, a drying zone and a re-dispersion zone improves the process. Drying of the catalyst particles immediately after the combustion of coke improves the operation of a platinum re-dispersion zone. The lower moisture content in the re-dispersion zone allows the equilibrium reaction between hydrogen chloride and oxygen on the one hand, and water and chlorine on the other hand to be shifted to the production of chlorine. This shift of the equilibrium reaction can be further improved by maintaining an oxygen-enriched environment within the platinum re-dispersion zone. The use of a much lower chloride concentration in the re-dispersion zone reduces the emissions of hydrogen chloride from the regeneration zone.Type: GrantFiled: January 9, 1991Date of Patent: February 11, 1992Assignee: UOPInventors: Paul R. Cottrell, Michael E. Fettis
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Patent number: 5087783Abstract: An improved process for the alkylation of benzene in the presence of an alkylation catalyst. The catalyst bed may be caused to move in a direction countercurrent to the movement of the benzene and olefin, or a portion of the catalyst bed is periodically removed and replaced. A regeneration step, whereby the catalyst is heated in a controlled oxygen atmosphere in order to reactivate the catalyst, is also described.Type: GrantFiled: November 9, 1990Date of Patent: February 11, 1992Assignee: Lummus Crest, Inc.Inventors: Roger C. Johnson, Daniel McCarthy, Andrei Rhoe
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Patent number: 5081083Abstract: Alternate, successive high temperature oxidation and reduction treatments, in either order, of intermetallic alloy hydrogenation and intermetallic alloy oxidation catalysts unexpectedly improves the impurity poisoning resistance, regeneration capacity and/or activity of the catalysts. The particular alloy, and the final high temperature treatment given alloy (oxidation or reduction) will be chosen to correspond to the function of the catalyst (oxidation or hydrogenation).Type: GrantFiled: February 12, 1990Date of Patent: January 14, 1992Assignee: The United States of America as represented by the Secretary of the Department of EnergyInventor: Randy B. Wright
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Patent number: 5075268Abstract: Disclosed herein is a method for the regeneration of a methanol-reforming talyst reduced in activity due to its use in a reaction in which methanol is modified, in the presence of water if necessary, to produce a hydrogen-containing gas. The catalyst contains copper as a principal component and at least one metal selected from the group consisting of zinc, nickel, chromium and aluminum. The method comprises exposing the catalyst to an atmosphere having a temperature of 120.degree.-650.degree. C. and a molecular oxygen concentration not higher than 5 mole %.Type: GrantFiled: January 30, 1991Date of Patent: December 24, 1991Assignees: Agency of Industrial Science and Technology, Extra Ministerial Bureau of Ministry of International Trade and IndustryInventors: Mitsuhiko Kurashige, Makoto Takiguchi, Noriko Matsuo
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Patent number: 5073529Abstract: A deactivated catalyst comprising a nonacidic zeolite and a Group VIII metal is regenerated by a two-step carbon burn process. The first oxidation step contacts the nonacidic zeolite catalyst with a halogen-free gaseous stream comprising oxygen and an inert gas at a first temperature sufficient to combust carbonaceous material while maintaining a substantial portion of the active Group VIII metal surface area withn the micropores of the nonacidic zeolite for a first period of time sufficient to substantially complete combustion of at least a portion the carbonaceous material at the first temperature. The second step contacts this nonacidic zeolite catalyst with a gaseous stream comprising oxygen and an inert gas at a second temperature sufficient to combust any remaining carbonaceous material for a second period of time sufficient to maintain a substantial portion of the active Group VIII metal surface area in the micropores of the nonacidic zeolite catalyst.Type: GrantFiled: December 20, 1989Date of Patent: December 17, 1991Assignee: Amoco CorporationInventors: Jeffrey T. Miller, Frank S. Modica, Sandra L. Cilluffo, Victor K. Shum
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Patent number: 5047376Abstract: The present invention relates to activated curing combinations for organic cationically polymerizable materials. The curing combinations are obtainable by activating a solution or a dispersion of an iron/arene salt and a polycarboxylic acid, an anhydride based on a polycarboxylic acid, or a polyisocyanate by heating or by irradiation with actinic radiation. The curable compositions containing these activated curing combinations can be used as sheathing or encapsulating materials for electronic components.Type: GrantFiled: July 27, 1989Date of Patent: September 10, 1991Assignee: Ciba-Geigy CorporationInventors: Dieter Baumann, Kurt Meier, Werner Margotte, Beat Muller
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Patent number: 5015611Abstract: A catalyst useful for promoting the conversion of organonitrogen and organosulfur compounds in a hydrocarbon-containing feedstock is regenerated in a method wherein a deactivated catalyst is contacted with a controlled amount of water prior to combustion of sulfur contaminants from the catalyst.Type: GrantFiled: February 28, 1990Date of Patent: May 14, 1991Assignee: Union Oil Company of CaliforniaInventor: Danford E. Clark
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Patent number: 4980325Abstract: A method for continuously or semi-continuously regenerating reforming catalyst by the recirculation of a gas stream advantageously controls the water content by using an oxygen-deficient makeup gas stream to supply the oxygen for combustion of coke. The volume of makeup gas entering the process is increased by reducing its oxygen concentration so that additional waste gases from the combustion of coke on the catalyst can be vented. The venting of additional gas from the circulating gas stream lowers the overall water concentration during the combustion of coke. The oxygen-deficient makeup gas stream can be supplied by oxygen and nitrogen separation from air. Where the production of the oxygen-deficient makeup gas stream also produces an oxygen-enriched stream, the oxygen-enriched stream is advantageously added to a catalyst reconditioning step for an increased dispersion of metals in the catalyst.Type: GrantFiled: June 12, 1989Date of Patent: December 25, 1990Assignee: UOPInventor: Paul A. Sechrist
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Patent number: 4975399Abstract: A spent hydrotreating catalyst composition is regenerated by a two-step heating process under such conditions as to substantially remove all carbonaceous deposits therefrom and to increase the average pore diameter of the catalyst composition. The thus-prepared regenerated catalyst composition is employed in a process for hydrotreating metal-containing oils.Type: GrantFiled: November 21, 1988Date of Patent: December 4, 1990Assignee: Phillips Petroleum CompanyInventor: Lloyd E. Gardner
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Patent number: 4942258Abstract: Process is disclosed for regeneration of a solid methacrylic acid catalyst wherein said catalyst is decoked in the presence of an oxygen-containing gas at an initial temperature no greater than 650.degree. F. and then by increasing the temperature incrementally to complete the regeneration at a temperature of from about 650.degree. F. to 800.degree. F.Type: GrantFiled: April 12, 1988Date of Patent: July 17, 1990Assignee: Amoco CorporationInventor: Thomas G. Smith
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Patent number: 4914065Abstract: The invention relates to a process for regenerating ceramic honeycomb filters by removing soot heaped thereon through combustion, which comprises the steps of controlling the combustion of the soot such that a time t (minutes), required for raising a temperature of an exhaust gas from a soot-ignition temperature, Tig, to Tig+200.degree. C., satisfies the following inequality. ##EQU1## in which: Q: a total flow rate of the waste gas per unit volume of the filter in the initial stage (Nm.sup.3 /min/l)V: the volume of the filter (l); andS: heaped soot per unit volume of the filter (g/l).Type: GrantFiled: October 20, 1988Date of Patent: April 3, 1990Assignee: NGK Insulators, Ltd.Inventors: Toshihiko Hijikata, Toshiaki Higuchi
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Patent number: 4902845Abstract: Catalyst activity life of an iron oxide-containing catalyst is extended by contacting such catalyst with a feedstream containing about 0.0001 to about 0.01 mole of oxygen per mole of feed in the substantial absence of an oxidation catalyst.Type: GrantFiled: November 21, 1988Date of Patent: February 20, 1990Assignee: Amoco CorporationInventors: Dae K. Kim, George A. McConaghy
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Patent number: 4900713Abstract: A method of stabilizing pyrophoric hydrotreating catalyst drums has been discovered. The dry catalyst is introduced into drums which have been purged with an inert gas such as nitrogen or carbon dioxide. A continuous layer of gelatinized starch is applied to the top of the catalyst, sealing it from air. The drum lid is clamped on and the catalyst is stored or transported. The gelatinized starch seal does not impair the catalyst for regeneration or metals reclaiming.Type: GrantFiled: August 19, 1988Date of Patent: February 13, 1990Assignee: Texaco, Inc.Inventors: Fred D. Brent Jr., Richard G. Nelson, William A. Ruff
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Patent number: 4888316Abstract: An active hydrotreating catalyst composition is prepared by a process comprising the steps of (a) grinding a spent hydrotreating catalyst containing carbonaceous deposits, (b) mixing the ground spent catalyst with an alumina-containing material (preferably alumina), (c) shaping (preferably extruding) the mixture of ground spent catalyst and alumina-containing material and (d) heating the shaped mixture so as to burn off carbonaceous deposits on the ground spent catalyst component. The thus-prepared active hydrotreating catalyst is used in a process for hydrotreating hydrocarbon containing feed streams (oils) which contain metal impurities.Type: GrantFiled: November 21, 1988Date of Patent: December 19, 1989Assignee: Phillips Petroleum CompanyInventors: Lloyd E. Gardner, Dennis R. Kidd
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Patent number: 4871700Abstract: A method of reactivating a catalyst having reduced activity as a result of having been used in producing an unsaturated aldehyde as a main product by catalytic vapor-phase oxidation reaction of propylene, isobutylene or tertiary butanol, said catalyst being a catalytic oxide comprising molybdenum, bismuth and iron with a Mo:Fe atomic ratio of 12:at least 0.1. The method comprises heat-treating the used catalyst at a temperature of 300.degree. to 500.degree. C. in the presence of a flowing oxidizing gas containing at least 5% by volume of molecular oxygen and at least 0.1% by volume of steam.Type: GrantFiled: May 12, 1988Date of Patent: October 3, 1989Assignee: Nippon Shokubai Kagaku Kogyo Co., Ltd.Inventors: Shin-ichi Uchida, Kozi Deguchi, Masamitsu Sasaki
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Patent number: 4855267Abstract: Process for the regeneration of deactivated copper-containing catalysts used in methanol or methyl formate dissociation reactions or in the steam reforming of methanol by first oxidizing then reducing the copper component of the copper-containing catalyst.Type: GrantFiled: April 25, 1988Date of Patent: August 8, 1989Assignee: E. I. Du Pont de Nemours and CompanyInventor: Wu-Hsun Cheng
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Patent number: 4853103Abstract: A catalytically dewaxed lubricating oil of improved oxidation stability is produced by catalytically dewaxing and hydrotreating the dewaxed product with a hydrotreating catalyst which has been oxidatively regenerated. The use of oxidative regeneration provides a hydrotreating catalyst which effectively sorbs aromatic components, especially the polycyclic aromatic liquids formed during the hydrogen activation of the dewaxing catalyst which pass out of the dewaxing reactor during the initial stages of each dewaxing cycle.Type: GrantFiled: April 11, 1988Date of Patent: August 1, 1989Assignee: Mobil Oil CorporationInventor: Mohsen N. Harandi
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Patent number: 4849092Abstract: The invention concerns a process for regenerating a hydrocarbon hydroconversion catalyst containing a carrier, at least one group VIII noble metal and a halogen or halogenated compound.It is characterized by an operation in two regeneration zones (1) and (2). The gas effluent from the first regeneration zone (1) is used to feed the second regeneration zone. During the step of burning coke deposited onto the catalyst in the first zone, the heat amount generated during the combustion is used for preheating the feed of said first zone. The temperature of the effluent of said first zone is reduced, through said exchanger, to a value adapted to perform the burning step in the second zone. Additional air is supplied before introducing the gas into said second zone (2) in order to obtain a suitable oxygen concentration.Type: GrantFiled: August 25, 1987Date of Patent: July 18, 1989Assignee: Institut Francais du PetroleInventors: Pierre Ham, Jean-Paul Dessapt, Didier Bischoff, Jean de Bonneville
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Patent number: 4798816Abstract: A process for treating a molecular sieve-containing alkylation catalyst to increase its selectivity for monoalkylation in which the alkylation catalyst is contacted with a feedstock comprising at least one organic compound under conditions such that a sufficient amount of carbonaceous material evenly deposits on the alkylation catalyst to substantially suppress its alkylation activity. The carbon-containing catalyst particles are then subjected to combustion by contacting them with a gaseous oxidizing agent at an elevated temperature to remove at least a portion of the carbonaceous material, preferably substantially all of the carbonaceous material, thereby increasing the selectivity of the catalyst for monoalkylation by at least about 1.0 percentage point. The resulting alkylation catalyst can be used to alkylate benzene and other aromatic compounds with ethylene, propylene or other olefins to produce high yields of ethylbenzene, cumene and other alkylated products.Type: GrantFiled: December 19, 1986Date of Patent: January 17, 1989Assignee: Union Oil Company of CaliforniaInventors: Charles T. Ratcliffe, John W. Ward
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Patent number: 4791080Abstract: Method for regenerating catalysts containing molybdenum, phosphorus, and vanadium in oxidic association and useful for the oxydehydrogenation of isobutyric acid or its lower esters to form methacrylic acid or its lower esters, by oxidizing the spent catalyst with an oxygen containing gas at temperatures from 200.degree. C. to 400.degree. C., suitably intermittently and in alternation with oxydehydrogenation.Type: GrantFiled: July 27, 1987Date of Patent: December 13, 1988Assignee: Rohm GmbHInventors: Wilheim Gruber, Klaus Langerbeins, Wolfgang Ruppert
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Patent number: 4752595Abstract: A process is described for regenerating a coke and poison deactivated noble metal-containing zeolite catalyst material. The activity of the catalyst after oxygen regeneration can be improved by treating the oxidized catalyst at temperatures from 100.degree. to 250.degree. C. (212.degree.-482.degree. F.) or lower, preferably 100.degree. to 200.degree. C. (212.degree.-392.degree. F.), or most preferably 150.degree. to 200.degree. C. (302.degree.-392.degree. F.), in a reducing atmosphere, as opposed to higher conventional reducing temperatures. The process permits catalyst reactivation by removing coke and other poisons, such as nitrogen, from the catalyst while avoiding excess agglomeration of the noble metals thereon.Type: GrantFiled: December 4, 1986Date of Patent: June 21, 1988Assignee: Mobil Oil CorporationInventors: Sharon B. McCullen, Y. Y. Peter Tsao, Stephen S. Wong
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Patent number: 4744962Abstract: A regeneration zone for fluid catalytic cracking contains ammonia (NH.sub.3) when the regeneration zone is operated in a partial combustion mode as defined by a content of CO of between 1 and 6 percent by volume. If the ammonia is not removed from the regeneration zone off gass, the same will be passed to a CO combustion zone where, in the presence of oxygen, CO is oxidized to CO.sub.2 and some of the ammonia will undesirably be oxidized to NO.sub.x. This invention reduces the presence of ammonia in the feed gas to a CO combustion zone of an FCC process by the introduction of a NO.sub.x -containing gas to dilute phase of a regeneration zone or to a regeneration zone off gas. Ammonia, NO.sub.x and oxygen present in the regeneration zone off gas of the regeneration zone, will tend to react to produce nitrogen and water vapor, which then is passed to the CO combustion zone for CO oxidation to CO.sub.2. Where the addition of NO.sub.x is made at temperatures greater than 1700.degree. F.Type: GrantFiled: July 22, 1987Date of Patent: May 17, 1988Assignee: Shell Oil CompanyInventors: Gregory L. Johnson, Norman C. Samish, Diana M. Altrichter
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Patent number: 4719189Abstract: A process is described for rejuvenating a coke-deactivated noble metal-containing zeolite catalyst material which comprises removing coke from a non-sulfided catalyst by contacting the catalyst with oxygen only in the presence of sulfur dioxide, and thereafter reducing the catalyst in the presence of a reducing agent such as hydrogen. The process permits catalyst reactivation by burning off coke from the catalyst while avoiding excessive agglomeration of the noble metal thereon.Type: GrantFiled: October 19, 1986Date of Patent: January 12, 1988Assignee: Mobil Oil CorporationInventor: Sowmithri Krishnamurthy
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Patent number: 4714689Abstract: Catalysts for the gas-phase reduction of aromatic nitro compounds to aromatic amines are regenerated by treatment of the catalyst, at elevated temperature, with a gas mixture which contains oxygen, inorganic and/or organic amines and/or nitrogen oxides and, where appropiate, steam.Type: GrantFiled: August 7, 1986Date of Patent: December 22, 1987Assignee: Bayer AktiengesellschaftInventors: Gunter Stammann, Zoltan Kricsfalussy, Helmut Waldmann, Joachim Schneider, Harald Medem
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Patent number: 4650780Abstract: A coke-deactivated noble metal-containing catalyst is sulfided with a sulfiding agent, e.g., H.sub.2 S in H.sub.2, then coke is burned from the sulfided catalyst by contacting the catalyst with oxygen, optionally in the presence of sulfur dioxide, and then the catalyst is reduced with a reducing agent, e.g., H.sub.2. The process permits burning off coke while avoiding excessive agglomeration of the noble metals on the catalyst.Type: GrantFiled: November 13, 1985Date of Patent: March 17, 1987Assignee: Mobil Oil CorporationInventors: Sowmithri Krishnamurthy, Quang N. Le, Stephen S. Wong
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Patent number: 4615992Abstract: The present invention provides for a process and associated apparatus for limiting the vertical mixing of catalyst in a fluidized catalyst regenerator so that spent catalyst entering the regenerator will remain at the top of the fluidized bed for a longer period of time. This is accomplished by employing a generally horizontally placed baffle device located between 2 ft.-4 ft. below the catalyst bed level in the regenerator.Type: GrantFiled: April 2, 1985Date of Patent: October 7, 1986Assignee: Air Products and Chemicals, Inc.Inventor: James R. Murphy
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Patent number: 4610972Abstract: A catalytic conversion system having sulfur-contaminated vessels and/or conduits upstream from the fixed catalytic bed is regenerated in situ by first flowing regenerating oxygen-containing gas having not more than 0.1 mol percent oxygen and at a temperature of above 850.degree. F., through the normal flow path of the vessels and/or conduits and then the fixed catalyst beds, wherein the sulfur contaminants are oxidized to sulfur dioxide which pass through the catalyst bed in the absence of sufficient oxygen to permit substantial conversion to harmful sulfur trioxide in the presence of catalyst containing a platinum group component on a porous inorganic oxide base, prior to removal of carbonaceous material from the catalyst.Type: GrantFiled: April 18, 1984Date of Patent: September 9, 1986Assignee: Chevron Research CompanyInventor: Thomas R. Hughes
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Patent number: 4604370Abstract: A process for regenerating a Mo.Bi-based multi-oxide catalyst the catalytic performance of which has deteriorated as a result of its use in vapor-phase catalytic oxidation of propylene or isobutene to prepare acrolein or methacrolein, respectively, which process comprises: heating the deteriorated Mo.Bi-based multi-oxide catalyst in an atmosphere consisting essentially of air at a temperature of 380.degree. C. to 540.degree. C., so as to attain at least partial restoration of the catalytic performance thereof.Type: GrantFiled: July 9, 1985Date of Patent: August 5, 1986Assignee: Mitsubishi Petrochemical Company, LimitedInventors: Kohei Sarumaru, Takeshi Shibano, Yoichi Ishii, Etsuji Yamamoto
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Patent number: 4600700Abstract: A process is described for regenerating a coke-deactivated platinum-containing zeolite catalyst material, which includes oxidizing the deactivated catalyst material in the presence of water under conditions which do not cause significant agglomeration of the platinum on the catalyst.Type: GrantFiled: December 28, 1984Date of Patent: July 15, 1986Assignee: Mobil Oil CorporationInventor: William D. McHale
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Patent number: 4581339Abstract: A method for reheating of a catalytic reactor by successive oxidations and reductions of a multiple oxidation state catalyst.Heat is added to the catalyst bed by a series of successive oxidation and reduction reactions occurring on the catalyst. Both catalyst oxidation and catalyst reduction are exothermic reactions, and both reactions generate heat to increase the temperature of the catalyst bed.Type: GrantFiled: March 18, 1985Date of Patent: April 8, 1986Assignee: Air Products and Chemicals, Inc.Inventors: Bharat L. Bhatt, John F. Kirner, Pradip Rao, William A. Schwartz
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Patent number: 4555495Abstract: A process is described for rejuvenating a coke-deactivated noble metal-containing zeolite catalyst material which comprises sulfiding the deactivated catalyst material by contacting with a sulfiding agent such as hydrogen sulfide-containing gas, removing coke from the sulfided catalyst by contacting the catalyst with oxygen in the presence of sulfur dioxide, and thereafter reducing the catalyst in the presence of a reducing agent such as hydrogen. The process permits catalyst reactivation by burning off coke from the catalyst while avoiding excessive agglomeration of the noble metals thereon.Type: GrantFiled: April 26, 1984Date of Patent: November 26, 1985Assignee: Mobil Oil CorporationInventor: Sowmithri Krishnamurthy