Patents Assigned to Chevron Research
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Patent number: 5413700Abstract: A method for reforming hydrocarbons comprising coating portions of a reactor system with a material more resistant to carburization, reacting the material with metal oxides existing in the portions of the reactor system prior to coating, fixating or removing at least a portion of the oxide in the metal oxides, and reforming hydrocarbons in the reactor system under conditions of low sulfur.Type: GrantFiled: January 4, 1993Date of Patent: May 9, 1995Assignee: Chevron Research and Technology CompanyInventors: John V. Heyse, Bernard F. Mulasky
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Patent number: 5409598Abstract: On-stream catalyst replacement hydroprocessing method wherein an upstream mixture of hydrogen and hydrocarbon liquid counter flows through a downwardly moving bed of hydroprocessing catalyst in a reactor vessel. The mixed feed stream of hydrogen and liquid hydrocarbon components enters a surge zone between the lower end of the reactor and a plenum zone to form a common pool under a conical support for the lower end of the downflowing catalyst bed. The mixed feed enters the plenum chamber through a plurality of passageways extending downwardly from the plenum zone to the same depth adjacent the lower end of the surge zone so that the liquid component normally prevents hydrogen from establishing independent paths before entering the plenum zone. Separation of the hydrogen and hydrocarbon liquid components from the mixed feed is thus assured to occur in the plenum zone directly below the pervious conical support to form a plurality of stepped concentric local reservoir rings under the conical support.Type: GrantFiled: March 21, 1994Date of Patent: April 25, 1995Assignee: Chevron Research CompanyInventors: David C. Kramer, Bruce E. Stangeland, David S. Smith, James T. McCall, Georgieanna Scheuerman, Robert W. Bachtel
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Patent number: 5407558Abstract: A method is provided of selecting operating parameters for an aromatization process having at least penultimate and final stages, each containing a respective catalyst, for optimum aromatic barrel per calendar day (AB/CD) production of product having a selected RON and/or over a particular run length. The catalyst lives are determined at constant LHSV for the penultimate and final stage catalysts for a given feed RON to each stage as a function of the change in RON from that of the feed to that of the C.sub.5+ effluent from the respective stage. The penultimate stage C.sub.5+ effluent RON is selected to be such that the lives of the catalysts in each stage are substantially equal. Preferably the yield of C.sub.5+ effluent from each stage and the life of the catalyst used in each stage is determined as a function of the pressure of that stage. The operating pressures of the stages are then selected to be within about 30% of that which gives the highest AB/CD.Type: GrantFiled: July 22, 1991Date of Patent: April 18, 1995Assignee: Chevron Research and Technology CompanyInventors: Jules M. Kline, Stephen J. Miller, Bernard F. Mulaskey
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Patent number: 5406014Abstract: Disclosed are methods for dehydrogenation of alkanes into alkenes in reactor systems of improved resistance to carburization under dehydrogenation conditions. The reactor walls are provided with a carburization and abrasion resistant protective layer by applying a metal plating, cladding or other coatings, such as painting, of a metal, such as Sb, As, Bi, Cu, Cr, Ga, Ge, In, Pb, Se, Te, Sn, particularly tin as a stannide layer, for forming a carburation resistant protective layer to a thickness of about 0.5 to 15 mils, effective to isolate the steel portion from hydrocarbons during the dehydrogenation process while avoiding any substantial liquid metal embrittlement. The protective layer is formed anchored to the steel portion through an intermediate carbide-rich bonding layer.Type: GrantFiled: January 4, 1994Date of Patent: April 11, 1995Assignee: Chevron Research and Technology CompanyInventors: John V. Heyse, Paul G. Johnson, Bernard F. Mulaskey
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Patent number: 5405525Abstract: A method for reforming hydrocarbons comprising coating portions of a reactor system with a material more resistant to carburization, reacting the material with metal sulfides existing in the portions of the reactor system prior to coating, fixating and removing at least a portion of the sulfur in the metal sulfides, and reforming hydrocarbons in the reactor system under conditions of low sulfur.Type: GrantFiled: January 4, 1993Date of Patent: April 11, 1995Assignee: Chevron Research and Technology CompanyInventors: John V. Heyse, Bernard F. Mulaskey
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Patent number: 5401386Abstract: Provided is a reforming process for producing a high purity benzene product using a non-acidic zeolitic catalyst. The high purity benzene is extracted from a light fraction of reformate that has less than 500 ppm by weight toluene. Generally, a hydrocarbon feed is reformed in a reformer under reforming conditions in the presence of a non-acidic catalyst to produce a reformate. That reformate is separated into a light fraction and a heavy fraction. The extraction unit, preferably an extractive distillation unit, is then used to separate the light fraction into an aromatic extract stream and a nonaromatic raffinate stream.Type: GrantFiled: July 23, 1993Date of Patent: March 28, 1995Assignee: Chevron Research and Technology CompanyInventors: Scott G. Morrison, Warren E. Brown
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Patent number: 5401365Abstract: A process is provided for separating benzene from non-aromatics in a highly aromatic stream containing olefins in a concentration range of from about 0.05 to about 5.0, which process comprises predistilling said highly aromatic stream to produce a distilled fraction having a concentration of C.sub.8 and heavier compounds of less than about 0.1 wt percent; and extracting said distilled fraction with a solvent comprising substituted morpholines in an extractive distillation zone to produce a highly-pure benzene stream.Type: GrantFiled: October 27, 1993Date of Patent: March 28, 1995Assignee: Chevron Research & TechnologyInventors: George T. Chen, Brenda M. Balaban, Gerd Emmrich, Bernhard Firnhaber
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Patent number: 5393407Abstract: A crystalline low-aluminum boron beta zeolite is prepared using a diquaternary ion as a template.Type: GrantFiled: June 26, 1992Date of Patent: February 28, 1995Assignee: Chevron Research CompanyInventors: Stacey I. Zones, Dennis L. Holtermann, Lawrence W. Jossens, Donald S. Santilli, Andrew Rainis
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Patent number: 5393309Abstract: A fuel additive composition comprising (a) a polyisobutenyl succinimide derived from ethylenediamine or diethylenetriamine, wherein the polyisobutenyl group has an average molecular weight of about 1200 to 1500 and (b) a nonvolatile paraffinic or naphthenic carrier oil, or a mixture thereof.Type: GrantFiled: May 19, 1994Date of Patent: February 28, 1995Assignee: Chevron Research and Technology CompanyInventor: Richard E. Cherpeck
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Patent number: 5393408Abstract: A process is disclosed for producing a hydrogenated lubricating oil base stock having improved stability. A lube oil base stock is contacted with hydrogen in a first hydrogenation zone under hydrogenation reaction conditions in the presence of a macroporous hydrogenation catalyst comprised of a particulate refractory inorganic oxide support component and a hydrogenation component. The macroporous hydrogenation catalyst has an acid site density of between about 0.015 and about 0.3 milliequivalents per gram of catalyst, a total pore volume greater than about 0.45 cm.sup.3 /g, and at least 10% of the total pore volume in macropores of diameter is greater than about 1000 Angstroms. A portion of the effluent from the first step is then contacted with hydrogen in a second hydrogenation zone under hydrogenation reaction conditions in the presence of a mesoporous hydrogenation catalyst comprised of a particulate refractory inorganic oxide support component and a hydrogenation component.Type: GrantFiled: April 30, 1992Date of Patent: February 28, 1995Assignee: Chevron Research and Technology CompanyInventors: James N. Ziemer, John M. Rosenbaum, Kristine L. Eiden
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Patent number: 5393410Abstract: This invention relates to catalyst compositions useful in converting hydrocarbonaceous oils. The catalyst comprises an ultra stable Y zeolite base, wherein said Y zeolite has a unit cell size greater than about 24.55 .ANG. and a crystal size less than about 2.8 microns, an amorphous cracking component, a binder, and a catalytic amount of hydrogenation component selected from the group consisting of a Group VI metal, a Group VIII metal, and mixtures thereof. The invention also relates to processes that are suitable for the catalyst use therein.Type: GrantFiled: October 20, 1993Date of Patent: February 28, 1995Assignee: Chevron Research and Technology CompanyInventors: Mohammad M. Habib, Arthur J. Dahlberg
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Patent number: 5391289Abstract: A method of fluid catalytic cracking of hydrocarbon feed which for rapid separation of the fluid catalytic cracking catalyst from the mixture of gases and products, utilizes a U-turn inertial separator directly coupled to cyclone separation.Type: GrantFiled: September 4, 1990Date of Patent: February 21, 1995Assignee: Chevron Research and Technology CompanyInventors: Ralph M. Forde, Bruce E. Stangeland
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Patent number: 5391287Abstract: The present invention relates to new crystalline zeolite SSZ-35 prepared by processes for preparing crystalline molecular sieves, particularly large pore zeolites, using conformationally constrained aza-polycyclic ring system templating agents.Type: GrantFiled: December 1, 1993Date of Patent: February 21, 1995Assignee: Chevron Research and Technology CompanyInventor: Yumi Nakagawa
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Patent number: 5389111Abstract: A low emissions diesel fuel with prescribed levels of aromatics and cetane number is disclosed which, when combusted in a diesel engine, results in lower emissions than the California Reference diesel fuel.Type: GrantFiled: June 1, 1993Date of Patent: February 14, 1995Assignee: Chevron Research and Technology CompanyInventors: Manuch Nikanjam, Richard F. Sullivan
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Patent number: 5389112Abstract: A low emissions diesel fuel with prescribed levels of aromatics and cetane number is disclosed which, when combusted in a diesel engine, results in lower emissions than the California Reference diesel fuel.Type: GrantFiled: August 13, 1993Date of Patent: February 14, 1995Assignee: Chevron Research and Technology CompanyInventors: Manuch Nikanjam, Richard F. Sullivan
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Patent number: 5382353Abstract: A pretreatment process is disclosed for increasing conversion and reducing the fouling rate of reforming catalysts wherein the catalyst is pretreated at a temperature from 1025.degree. F. to 1275.degree. F. in a reducing atmosphere prior to contacting the catalyst with a hydrocarbon feed in the presence of hydrogen.Type: GrantFiled: November 15, 1993Date of Patent: January 17, 1995Assignee: Chevron Research & Technology Co., a Div. of Chevron U.S.A. Inc.Inventors: Bernard F. Mulaskey, Robert L. Hise, Steven E. Trumbull, William J. Cannella, Robert A. Innes
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Patent number: 5380345Abstract: Polyalkyl nitro and amino aromatic esters having the formula: ##STR1## wherein A.sub.1 is nitro, amino, N-alkylamino wherein the alkyl group contains 1 to 6 carbon atoms, or N,N-dialkylamino wherein each alkyl group independently contains 1 to 6 carbon atoms; R.sub.1 and R.sub.2 are independently hydrogen, hydroxy, lower alkyl having 1 to 6 carbon atoms, or lower alkoxy having 1 to 6 carbon atoms; R.sub.3 is a polyalkyl group having a weight average molecular weight in the range of about 450 to 5,000; and x is an integer from 0 to 10.The polyalkyl nitro and amino aromatic esters of formula I are useful as fuel additives for the prevention and control of engine deposits.Type: GrantFiled: December 3, 1993Date of Patent: January 10, 1995Assignee: Chevron Research and Technology CompanyInventor: Richard E. Cherpeck
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Patent number: 5376259Abstract: A naphtha feed is contacted in a penultimate aromatic forming stage under catalytic aromatic forming conditions with a first catalyst. The effluent from the penultimate stage is contacted in a final aromatic forming stage under catalytic aromatic forming conditions and at substantially the same pressure as is maintained in the penultimate stage with a second catalyst. The pressure is selected to provide optimal aromatic production per calendar day from the final stage.Type: GrantFiled: July 22, 1991Date of Patent: December 27, 1994Assignee: Chevron Research and Technology CompanyInventors: Jules M. Kline, Stephen J. Miller, Bernard F. Mulaskey
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Patent number: 5375660Abstract: Minerals in a subterranean formation are dissolved by treating them in the presence of an organic acid with a fluoride-containing compound having a concentration in the range of from 0.007 N to 0.05 N. The hydrogen ion concentration can be less than 0.02 N, preferably less than 0.004 N. The fluoride-containing compound can be hydrofluoric acid. Alternatively, the minerals can be treated by applying alternating stages of a solution of fluoride salt, such as ammonium fluoride or ammonium bifluoride, and an organic acid, such as acetic acid. The treatment can be done in a formation at a temperature of at least 350.degree. F.Type: GrantFiled: October 7, 1992Date of Patent: December 27, 1994Assignee: Chevron Research and Technology CompanyInventor: C. Dean Wehunt
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Patent number: 5376260Abstract: Heavy waxy oil is dewaxed by a mild cracking and isomerization process using a catalyst comprising SSZ-32 and at least one Group VIII metal. The heavy oil contains naphthenic wax, which includes only a relatively small amount of normal alkanes. Naphthenic wax containing a minor amount of oil may also be dewaxed using the process.Type: GrantFiled: April 5, 1993Date of Patent: December 27, 1994Assignee: Chevron Research and Technology CompanyInventors: Donald S. Santilli, Stacey I. Zones