Patents Assigned to Chevron Research
  • Method for enhancing the recovery of petroleum from an oil-bearing formation using a mixture including anionic and cationic surfactants
    Patent number: 5246072
    Abstract: A foam-forming composition comprising a mixture of at least one anionic surfactant and at least one cationic surfactant can effectively form a foam in a variety of formations including an oil-wet environment. In particular, this composition can be employed in a method which comprises at least periodically injecting a gas and this foam-forming composition into an oil-bearing formation to drive oil to a production well. In this composition, the ratio of the at least one anionic surfactant to the at least one cationic surfactant is selected so that the surfactants do not form substantial amounts of precipitate when mixed together. In certain environments, e.g., when the formation contains upwards of 20% total dissolved solids and/or a divalent metal ion concentration up to about 20,000 ppm, the composition can further contain at least one salt-tolerance additive, e.g., a nonionic surfactant.
    Type: Grant
    Filed: August 14, 1991
    Date of Patent: September 21, 1993
    Assignee: Chevron Research and Technology Company
    Inventors: Rawls H. Frazier, Jr., Donald L. Kuehne, Willie Horn, Jr., Jeremy Cantor
  • Wax isomerization using catalyst of specific pore geometry
    Patent number: 5246566
    Abstract: The present invention relates to a process for producing a lube oil having a low pour point and excellent viscosity and viscosity index comprising isomerizing a waxy feed over a catalyst comprising a molecular sieve having generally oval 1-D pores having a minor axis between about 4.2 .ANG. and about 4.8 .ANG. and a major axis between about 5.4 .ANG. and about 7.0 .ANG. and at least one group VIII metal. SAPO-11, SAPO-31, SAPO-41, ZSM-22, ZSM-23 and ZSM-35 are examples of useful catalysts.
    Type: Grant
    Filed: June 29, 1992
    Date of Patent: September 21, 1993
    Assignee: Chevron Research and Technology Company
    Inventor: Stephen J. Miller
  • Polyurea-based grease with metal borate and antimony additives
    Patent number: 5246605
    Abstract: Disclosed is a grease composition comprising a major amount of a lubricating oil base vehicle, a polyurea gellant in an amount sufficient to thicken the base vehicle to grease consistency, an alkali-metal borate in an amount sufficient to impart extreme-pressure properties to the grease and from 0.1 to 10.0 mass percent of antimony dithiocarbamate.
    Type: Grant
    Filed: October 26, 1992
    Date of Patent: September 21, 1993
    Assignee: Chevron Research Company
    Inventor: Paul F. Vartanian
  • Grease composition with improved extreme pressure and antiwear properties
    Patent number: 5246604
    Abstract: Disclosed is a grease composition comprising a major amount of a lubricating oil base vehicle, a lithium gellant in an amount sufficient to thicken the base vehicle to grease consistency, an alkali-metal borate in an amount sufficient to impart extreme-pressure properties to the grease and from 0.1 to 10.0 mass percent of antimony dithiocarbamate.
    Type: Grant
    Filed: October 26, 1992
    Date of Patent: September 21, 1993
    Assignee: Chevron Research Company
    Inventor: Paul F. Vartanian
  • Lubricating oil compositions for internal combustion engines having silver bearing parts
    Patent number: 5244591
    Abstract: Essentially chlorine-free lubricating compositions having a TBN of 10-30 designed for use in internal combustion engines having silver bearing parts which provide protection for said bearings via the incorporation therein of certain unsaturated aliphatic carboxylic acids. An additive concentrate for said lubricating compositions is also disclosed.
    Type: Grant
    Filed: March 23, 1992
    Date of Patent: September 14, 1993
    Assignee: Chevron Research and Technology Company
    Inventor: Wesley A. Middleton
  • Method for reducing the production of liquids from a gas well
    Patent number: 5244043
    Abstract: A method for reducing the amount of liquids produced from a selected geologic formation of a gas producing well is disclosed. A solution comprising controlled quantities of a scaling cation brine and scaling anion brine such that a scale will precipitate, and a controlled quantity of a scale inhibitor such that the scale precipitation will be delayed, is injected into the formation. The well is then shut-in long enough to allow the injected mixture to precipitate scale and to reduce the permeability of the formation such that a substantial portion of liquids that had been produced before, no longer are produced upon a resumption of gas production.
    Type: Grant
    Filed: November 19, 1991
    Date of Patent: September 14, 1993
    Assignee: Chevron Research and Technology Company
    Inventor: Patrick J. Shuler
  • Dimeric and tetrameric cyclopentadienyl group 6B metal alpha-olefin polymerization catalysts and process for polymerizing alpha-olefins
    Patent number: 5240895
    Abstract: Disclosed is a catalyst system for the homopolymerization and copolymerization of alpha-olefins having 2-8 carbon atoms, said catalyst system comprising a dimeric or tetrameric cyclopentadienyl Group 6b metal compound in which the metal has an oxidation state of +2, said Group 6b metal compound being supported on an inorganic support. The catalyst system may also contain a Group 2 or Group 3 metal alkyl compound cocatalyst.
    Type: Grant
    Filed: November 6, 1992
    Date of Patent: August 31, 1993
    Assignee: Chevron Research and Technology Company
    Inventors: Michael J. Carney, David L. Beach
  • Processes for recovering precious metals
    Patent number: 5238662
    Abstract: Disclosed is a process for recovering precious metals using a combination of smelting and an effective utilization of molten salt chlorination. More specifically, disclosed is a process including the steps of (i) contacting, for example, a matte with a chloride salt containing at least one of potassium, cesium or rubidium, but not sodium or lithium to form a matte/salt solids mixture, (ii) introducing the solids mixture into a chloride melt having a temperature ranging from 300.degree. C. to 650.degree. C., said melt containing at least one of potassium, cesium, rubidium, sodium or lithium, (iii) introducing a chlorine containing gas into the melt, and (iv) maintaining the salt ratio in the matte/salt mixture at a stoichiometrically equivalent amount with the precious metals and base metals contained in the matte.
    Type: Grant
    Filed: May 11, 1992
    Date of Patent: August 24, 1993
    Assignee: Chevron Research Company
    Inventor: Michael Dubrovsky
  • Process for removing dissolved organics from aqueous compositions
    Patent number: 5236590
    Abstract: A process is disclosed for removing dissolved organics from an aqueous composition, said composition comprising water, carbon dioxide and dissolved organics, and said composition having a pH of 6.5 or less and an inlet organics concentration. The process comprises the steps of feeding said aqueous composition to a centrifugal separation zone, preferably to a hydrocyclone, depressurizing said composition in said centrifugal separation zone to regasify at least a portion of said carbon dioxide. An aqueous product stream is removed from the centrifugal separation zone wherein the concentration of said organics is less than said inlet organics concentration. The process is particularly useful in the cleanup of industrial wastewater, and also for removing organics from water produced in petroleum production operations.
    Type: Grant
    Filed: November 21, 1991
    Date of Patent: August 17, 1993
    Assignee: Chevron Research and Technology Company
    Inventors: Steven F. Sciamanna, Michael Dubrovsky
  • Method for foam emplacement in gas flooding for enhanced oil recovery
    Patent number: 5234054
    Abstract: A method for improving the sweep efficiency of gas or steam flooding operations by reducing the permeability of relatively high permeability thief zones of an oil bearing subterranean reservoir having heterogeneous and/or fracture permeability and that is penetrated by at least one well is disclosed. A controlled quantity of a surfactant is injected into a high-permeability zone of a reservoir. Controlled quantities of a gas and a subsequent surfactant are then injected, simultaneously or alternatively into the same well, so that a controlled amount of foam having a controlled quality is generated in the high permeability zone, thereby reducing permeability. Following foam emplacement, a chase gas may be injected, and the steps of injecting surfactant and gas may be repeated as necessary to lower the gas-oil ration of non-problem offset producing wells to a preset limit.
    Type: Grant
    Filed: September 12, 1991
    Date of Patent: August 10, 1993
    Assignee: Chevron Research and Technology Company
    Inventor: Shang Chou
  • Hydrocracking process with polycyclic aromatic dimer removal
    Patent number: 5232577
    Abstract: A process for separation and removal of stable polycyclic aromatic dimer foulants from refinery process streams by blending a paraffinic stream with a portion of heavy effluent from a hydrocracking reactor to induce precipitation of foulant, which may then be separated and removed from the hydrocracker. Additional embodiments include introduction of flocculating agents and adjusting the temperature of the blend.
    Type: Grant
    Filed: August 14, 1990
    Date of Patent: August 3, 1993
    Assignee: Chevron Research and Technology Company
    Inventors: John C. Fetzer, John M. Rosenbaum, Robert W. Bachtel, Dennis R. Cash, David G. Lammel
  • Lubricating compositions
    Patent number: 5232616
    Abstract: Provided are lubricating oil compositions which contain (a) a mixture comprising an oil-soluble alkali metal compound and certain polyalkenyl succinimide or (b) alkali metal salts of said polyalkenyl succinimides.
    Type: Grant
    Filed: August 21, 1990
    Date of Patent: August 3, 1993
    Assignee: Chevron Research and Technology Company
    Inventors: James J. Harrison, Curtis B. Campbell
  • Methods for preparing substantially pure SAPO-31 silicoaluminophosphate molecular sieve
    Patent number: 5230881
    Abstract: Disclosed herein is a process for preparing substantially pure crystalline SAPO-31 molecular sieve. In particular, disclosed are methods for preparing SAPO-31 which methods employ specified crystallization media with specified pHs. When such crystallization media are employed, the resulting SAPO-31 is substantially pure and has no contamination from crystalline SAPO-11 silicoaluminophosphate molecular sieve.
    Type: Grant
    Filed: May 6, 1992
    Date of Patent: July 27, 1993
    Assignee: Chevron Research & Technology Co.
    Inventor: Stephen J. Miller
  • Retarding skin formation on hot asphalt
    Patent number: 5224992
    Abstract: Organotin hydrides are effective in retarding oxidative skin formation in asphalts maintained at elevated temperature.
    Type: Grant
    Filed: July 1, 1992
    Date of Patent: July 6, 1993
    Assignee: Chevron Research and Technology Company
    Inventor: Edgar L. McGinnis
  • Method of making molecular sieves
    Patent number: 5225179
    Abstract: A method for synthesizing molecular sieves is disclosed. The method comprises preparing an aqueous mixture comprising:a) a source zeolite, wherein said source zeolite contains sodalite substructures and has a tetrahedra atom density of less than about 15 TO.sub.2 per 1000 .ANG..sup.3, and wherein said source zeolite has a silica/alumina mole ratio greater than 200; an alkali metal oxide; and an organic template, and wherein said aqueous mixture has a composition in terms of mole ratios of oxides falling within the following ranges:______________________________________ M+/SiO.sub.2 = 0.01-1.00 OH-/SiO.sub.2 = 0.15-0.80 H.sub.2 O/SiO.sub.2 = 20-120 Q/SiO.sub.2 = 0.10-1.00 SiO.sub.2 /Y.sub.2 O.sub.
    Type: Grant
    Filed: August 27, 1992
    Date of Patent: July 6, 1993
    Assignee: Chevron Research and Technology Company
    Inventors: Stacey I. Zones, Yumi Nakagawa
  • Method for making anhydride from ester using a palladium-containing catalyst system
    Patent number: 5220060
    Abstract: Methylene and oxymethylene bis-esters are produced by the reaction of an aliphatic ester of a carboxylic acid, formaldehyde and carbon monoxide in the presence of a catalytic amount of a Group VIII noble transition metal compound, an iodide or bromide promoter, and a proton donor.
    Type: Grant
    Filed: December 20, 1991
    Date of Patent: June 15, 1993
    Assignee: Chevron Research and Technology Company
    Inventors: Seymour J. Lapporte, William G. Toland
  • Ethylene-alkyl acrylate copolymer saponification process
    Patent number: 5218057
    Abstract: Disclosed is a method for saponifying an ethylene-alkyl acrylate copolymer comprising mixing together an ethylene-alkyl acrylate copolymer and an aqueous solution of an inorganic alkali metal base at a temperature sufficient for saponification to take place and at which the ethylene-alkyl acrylate copolymer undergoes a phase change.
    Type: Grant
    Filed: July 10, 1991
    Date of Patent: June 8, 1993
    Assignee: Chevron Research and Technology Company
    Inventors: Victor P. Kurkov, Leslie P. Theard
  • Resid catalyst with high metals capacity
    Patent number: 5215955
    Abstract: A catalyst, and method of preparing and using a catalyst, for the hydrodesulfurization of metal-containing heavy feedstocks, which has improved catalytic life and metals capacity. The catalyst contains Group VIB and Group VIII metals or metal compounds on a support comprising alumina wherein the support has at least 80 percent of said pore volume in pores having a diameter of between 110 and 190 .ANG. and at least 70 percent of said pore volume in pores having a diameter between 130 and 200 .ANG..
    Type: Grant
    Filed: October 2, 1991
    Date of Patent: June 1, 1993
    Assignee: Chevron Research and Technology Company
    Inventor: Richard S. Threlkel
  • Hydrocarbon conversion processes using SSZ-31
    Patent number: 5215648
    Abstract: Hydrocarbon conversion processes using a crystalline zeolite SSZ-31.
    Type: Grant
    Filed: January 3, 1992
    Date of Patent: June 1, 1993
    Assignee: Chevron Research and Technology Company
    Inventors: Stacey I. Zones, Thomas V. Harris, Andrew Rainis, Donald S. Santilli
  • Spraying device with a replaceable cartridge
    Patent number: 5213264
    Abstract: A spraying device having a sprayer head and an interchangeable, disposable, recyclable and/or biodegradable, and attachable cartridge, capable of diluting and dispensing a chemical. The device has a rotatable barrel valve to select whether to fill the cartridge, spray the diluted chemical, or prevent any flow. The device further has a pair of coupling tubes which permit the easy connection of the sprayer head to the cartridge in a way to cause, by aspiration, the partially diluted chemical to enter the sprayer head for further mixing and discharge. A rupturable or replaceable membrane is placed across the top of the cartridge to contain the concentrated chemical prior to use. A plug closure permits the addition of a chemical to the cartridge.
    Type: Grant
    Filed: October 11, 1990
    Date of Patent: May 25, 1993
    Assignee: Chevron Research and Technology Company
    Inventor: James J. Styne