Patents Represented by Attorney Mark D. Marin
  • Patent number: 7241375
    Abstract: A heavy hydrocarbon composition with utility as a heavy hydrocarbon base stock comprising at least 95 wt % paraffin molecules, of which at least 90 wt % are isoparaffin, containing hydrocarbon molecules having consecutive numbers of carbon atoms, is a liquid at 100° C., at which temperature its kinematic viscosity, as measured by ASTM D-445, is above 8 cSt, has an initial boiling point of least 850° F. (454° C.) and an end boiling point of at least 1000° F. (538° C.), wherein the branching index (BI), as measured by the percentage of methyl hydrogens, and the branching proximity (CH2>4), as measured by the percentage of recurring methylene carbons which are four or more carbon atoms removed from an end group or branch, of said isoparaffinic hydrocarbon molecules, are such that: (a) BI?0.5(CH2>4)<15; and (b) BI+0.85(CH2>4)<45; as measured over the heavy hydrocarbon composition as a whole.
    Type: Grant
    Filed: August 29, 2003
    Date of Patent: July 10, 2007
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Jack Wayne Johnson, Adeana Richelle Bishop, William Berlin Genetti, Loren Leon Ansell, Rocco Anthony Fiato
  • Patent number: 7096931
    Abstract: Ribbed heat exchange tubes in which the aspect ratio of the ribs is less than 5, provide greater indirect heat exchange than conventional heat exchange tubes with or without fins, when used in a slurry comprising a liquid phase, in which is dispersed flowing gas bubbles or particulate solids and flowing gas bubbles. The ribs, and typically also the longitudinal axis of the heat exchange tubes, are aligned in a direction parallel to, or spirally along the gas bubble flow direction. This is useful to increase either (i) the productivity of a slurry Fischer-Tropsch hydrocarbon synthesis reactor without an increase in the temperature in the reactor or (ii) increasing the production of higher molecular weight hydrocarbons by reducing the reaction temperature at a given feed conversion.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: August 29, 2006
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Min Chang, Richard Frank Bauman
  • Patent number: 7008966
    Abstract: A removable filter for separating and filtering slurry liquid from solid particles includes one or more filter sections connected by a filtrate conduit. Each section comprises a plurality of vertical, hollow, sintered metal filter elements horizontally arranged across a manifold connected to a hollow filtrate conduit. The sections are vertically stacked and connected by the conduit(s) to form the filter which is removably secured in the slurry by means which permit it to be removed vertically up and out of the top of the reactor. This filter has a high surface area to volume ratio and is useful for removing the liquid hydrocarbon products from a slurry hydrocarbon synthesis reactor and can easily be replaced without having to drain out the slurry.
    Type: Grant
    Filed: October 5, 2004
    Date of Patent: March 7, 2006
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Charles W. Degeorge, Barry J. Thompson
  • Patent number: 6972275
    Abstract: Novel oil-in-oil emulsions and methods of lubrication using the same are provided. The lubricants are stable emulsions of carrier fluid and high viscosity fluid that display superior properties related to lubricating film thickness and reduced shear strength.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: December 6, 2005
    Assignee: ExxonMobil Research and Engineering Company
    Inventor: Thomas R. Forbus, Jr.
  • Patent number: 6846848
    Abstract: A hydrocarbon wax product from a hydrocarbon synthesis slurry comprising liquid synthesis product and catalyst particles is purified by introducing a portion of hydrocarbon synthesis slurry from a hydrocarbon synthesis zone to a treatment zone in which a treatment gas contacts the hydrocarbon synthesis slurry. Hydrogen or a hydrogen-containing gas is useful as the treatment gas. The gas treatment removes impurities from the hydrocarbon wax portion of the hydrocarbon synthesis slurry. Purified wax product is separated and removed in situ via wax withdrawal means. This avoids or minimizes the need for further treating the wax product.
    Type: Grant
    Filed: August 23, 2002
    Date of Patent: January 25, 2005
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Robert Jay Wittenbrink, Loren Leon Ansell, Daniel Francis Ryan, Louis Francis Burns
  • Patent number: 6846778
    Abstract: A synthetic, isoparaffinic heavy hydrocarbon composition useful as a heavy lubricant base stock contains hydrocarbon molecules having consecutive numbers of carbon atoms, is a liquid at 100° C., at which temperature its kinematic viscosity is above 8 cSt and has respective initial and end boiling points of at least 850 and 1000° F. (454 and 538° C.). The branching index BI and the branching proximity CH2>4 of the isoparaffinic hydrocarbon molecules, are such that: BI?0.5(CH2>4)<15; and??(a) BI+0.85(CH2>4)<45;??(b) as measured over the hydrocarbon composition as a whole.
    Type: Grant
    Filed: October 8, 2002
    Date of Patent: January 25, 2005
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Jack Wayne Johnson, Adeana Richelle Bishop, William Berlin Genetti, Loren Leon Ansell, Rocco Anthony Fiato
  • Patent number: 6833064
    Abstract: A wide cut Fischer-Tropsch derived diesel fuel is produced wherein the distillate boils in a wider range than a conventional diesel fuel while providing favorable low temperature properties and environmentally beneficial effects. In particular, the fuel comprises a hydrocarbon distillate derived from the Fischer-Tropsch process having T90 greater than 640° F. (338° C.) but less than 1000° F. (538° C.) and a cold filter plugging point less than or equal to +5° C.
    Type: Grant
    Filed: August 3, 2001
    Date of Patent: December 21, 2004
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Paul Joseph Berlowitz, Robert Jay Wittenbrink, Daniel Francis Ryan, William Berlin Genetti, Jack Wayne Johnson
  • Patent number: 6827842
    Abstract: A laser beam reflected by wax crystals is used in determining the wax crystallization temperature of a hot dewaxing solvent upstream of solvent chillers. This is automatically achieved by an on-line method from a remote control point, in which a slipstream of solvent is passed through an attached solvent loop into a sample chamber in the loop, without being exposed to ambient conditions. As the sample is cooled, the beam reflections are detected and indicate the wax to crystallization temperature. Corrective measures can then be taken to prevent fouling of the chillers, if need be.
    Type: Grant
    Filed: October 19, 2001
    Date of Patent: December 7, 2004
    Assignee: ExxonMobil Research & Engrg. Co.
    Inventors: Brent England Beasley, Randall Stephen Lachine
  • Patent number: 6825154
    Abstract: Lubricating oil formulations comprising base oil, sulfur-phosphorous anti-wear/extreme pressure agents and hindered phenol antioxidants which anti-wear/extreme-pressure agents and hindered phenolic antioxidants are prone to crystal formation wherein the base oil is characterized as having a saturates content of less than 99% are stabilized against crystal formation by the addition of a minor amount of a high molecular weight di- or polycarboxylic acid anhydride, or mixture thereof.
    Type: Grant
    Filed: July 22, 2002
    Date of Patent: November 30, 2004
    Assignee: ExxonMobil Research and Engineering Company
    Inventor: David Gary Lawton Holt
  • Patent number: 6822131
    Abstract: Clean distillate useful as a diesel fuel or diesel blending stock is produced from Fischer-Tropsch wax by separating wax into heavier and lighter fractions; further separating the lighter fraction and hydroisomerizing the heavier fraction and that portion of the light fraction below about 500° F. The isomerized product is blended with the untreated portion of the lighter fraction.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: November 23, 2004
    Assignee: ExxonMobil Reasearch and Engineering Company
    Inventors: Paul J. Berlowitz, Robert J. Wittenbrink, Bruce R. Cook
  • Patent number: 6777451
    Abstract: A process for enhancing metal catalysts for carbon monoxide hydrogenation comprising reducing the catalyst so that at least a portion is in the metallic state, impregnating under a non-oxidative atmosphere with a solution of a salt of at least one metal, optionally in combination with at least one of an ammonium salt, an alkyl ammonium salt, a weak organic acid and ammonia, oxidizing with a gaseous oxidant in the presence of the impregnating solution, and reducing to form an active catalyst. Used catalysts enhanced by the process are initially treated to decrease their hydrocarbon content. The treatment may be carried out in a single reactor, or by carrying out up to all steps after catalyst may be withdrawn from a reactor and returned to at least one reactor, both preferably during operations. Up to all steps may be effected in a subsequent reactor, or in specialized apparatus.
    Type: Grant
    Filed: January 29, 2002
    Date of Patent: August 17, 2004
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Russell John Koveal, Michel Daage, Charles Harrison Mauldin, Janet Renee Clark
  • Patent number: 6776898
    Abstract: A novel process for forming hydrocarbon waxes from synthesis gas is disclosed. This invention teaches a process whereby a Fischer-Tropsch wax can be formulated such that the wax softness as defined by ASTM Standard Test Method for Needle Penetration of waxes (ASTM D-1321) can be adjusted to within a region most preferred for end use applications while simultaneously removing undesirable impurities, such as oxygenates (e.g., primary alcohols), olefins, and trace levels of aromatics. In a Fischer-Tropsch reactor, Fischer-Tropsch wax is formed from synthesis gas in a catalyzed reaction. The Fischer Tropsch wax is then subjected to a relatively mild hydroprocessing over a hydroisomerization catalyst under conditions such that essentially no boiling point conversion is obtained, but yet chemical conversions (e.g., hydrogenation and mild isomerization) occur yielding a high purity, hydrocarbon wax product of reduced hardness.
    Type: Grant
    Filed: April 4, 2000
    Date of Patent: August 17, 2004
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Robert J. Wittenbrink, Daniel Francis Ryan
  • Patent number: 6765026
    Abstract: A process for the preparation of a catalyst useful for conducting carbon monoxide hydrogenation reactions, particularly Fischer-Tropsch reactions; the catalyst compositions, use of the catalyst compositions for conducting such reactions, and the products of these reactions. The steps of the process for producing the catalyst comprise impregnating a powder, or particulate refractory inorganic oxide solids, preferably silica, with a) a soluble compound or salt of a catalytic metal of the Iron Group, preferably cobalt, and b) a soluble compound, or salt, of a Group VIII noble metal, preferably platinum, suitably by sequential contact of the solids with a solution of (a) and a solution of (b), by sequential contact of the solids with a solution of (b) and a solution of (a), or by contact with a solution which contains both (a) and (b).
    Type: Grant
    Filed: February 28, 2003
    Date of Patent: July 20, 2004
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Alla Jurievna Krylova, Albert L'Vovich Lapidus, Maria Vadimovna Tsapkina
  • Patent number: 6755961
    Abstract: A Fischer-Tropsch derived distillate fraction is blended with either a raw virgin condensate fraction or a mildly hydrotreated virgin condensate to obtain a stable inhibited distillate fuel.
    Type: Grant
    Filed: July 25, 2000
    Date of Patent: June 29, 2004
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Paul J Berlowitz, Robert J. Wittenbrink, Bruce R. Cook
  • Patent number: 6753354
    Abstract: There is provided a process for hydrocarbon synthesis wherein a supported metal catalyst for hydrogenating carbon monoxide to form a mixture of hydrocarbons is regenerated by decreasing its hydrocarbon content, impregnating under a non-oxidative atmosphere with a solution of at least one member selected from the group consisting of ammonium salts, alkyl ammonium salts and weak organic acids, optionally including ammonia, oxidizing with a gaseous oxidant in the presence of the impregnating solution, activating the catalyst by reduction with hydrogen at elevated temperatures and reusing the catalyst. The treatment may be carried out in a single reactor, or by carrying out up to all steps after catalyst has been withdrawn therefrom and returned to at least one reactor. Up to all steps subsequent to decreasing the hydrocarbon content may be effected in a subsequent reactor, or in specialized apparatus.
    Type: Grant
    Filed: January 29, 2002
    Date of Patent: June 22, 2004
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Russell John Koveal, Michel Daage, Eric Baochun Shen
  • Patent number: 6753351
    Abstract: A process for activating a supported metal catalyst or catalyst precursor useful for the hydrogenation of carbon monoxide to form a mixture of hydrocarbons, comprising reducing with a hydrogen-containing gas at elevated temperature so that at least a portion is in the metallic state, impregnating under a non-oxidizing atmosphere with a solution of at least one member selected from the group consisting of ammonium salts, alkyl ammonium salts and weak organic acids, optionally further including ammonia, to the point where it has absorbed a volume of solution equal to at least about 10% of its calculated pore volume, oxidizing with a gaseous oxidant in the presence of the impregnating solution and reducing with hydrogen-containing gas at elevated temperatures to form an active catalyst. The steps beginning with the impregnation may be repeated. Optionally, the catalyst may be calcined after the oxidation step and/or passivated after activation.
    Type: Grant
    Filed: January 29, 2002
    Date of Patent: June 22, 2004
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Janet Renee Clark, Michel Daage, Russell John Koveal
  • Patent number: 6753286
    Abstract: There is provided a process for renewing the activity of used, supported metal catalysts for the hydrogenation of carbon monoxide to form a mixture of hydrocarbons comprising decreasing the hydrocarbon content of the catalyst, impregnating said catalyst under an non-oxidative atmosphere with a solution at least one weak organic acid, preferably a mono- or di-carboxylic acid, to the point where it has absorbed a volume of said solution equal to at least about 10% of its calculated pore volume, oxidizing the catalyst with a gaseous oxidant in the presence of the impregnating solution and activating the catalyst by reduction with hydrogen at elevated temperatures. Optionally, the catalyst is calcined after the oxidation step, and passivated after the activation step. A preferred means of decreasing the hydrocarbon content of the catalyst is contacting it with a hydrogen-containing gas at elevated temperatures.
    Type: Grant
    Filed: January 29, 2002
    Date of Patent: June 22, 2004
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Janet Renee Clark, Russell John Koveal, Michel Daage
  • Patent number: 6717024
    Abstract: A slurry Fischer-Tropsch hydrocarbon synthesis process for synthesizing liquid hydrocarbons from synthesis gas in a synthesis reactor also hydroisomerizes the synthesized hydrocarbon liquid, which comprises the slurry liquid, in one or more lift reactors immersed in the slurry body in the synthesis reactor. A monolithic catalyst is preferably used for the hydroisomerization, and slurry circulation up through the lift reactors from the surrounding slurry body, is achieved at least in part by the lift action of the hydroisomerization treat gas. Preferably, catalyst particles are also removed before the slurry contacts the catalyst. Hydroisomerization occurs while the synthesis reactor is producing hydrocarbons, without interfering with the synthesis reaction. A gas bubble reducing downcomer may be used to produce and feed the gas bubble reduced slurry into the lift reactor, thereby providing a hydraulic head assist in the slurry circulation up through and out of the lift reactor.
    Type: Grant
    Filed: November 6, 2001
    Date of Patent: April 6, 2004
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Robert Jay Wittenbrink, Charles John Mart, Janet Renee Clark, Jennifer Schaefer Feeley
  • Patent number: 6695965
    Abstract: A wax blending process is disclosed which retains the desirable properties of a Fischer-Tropsch wax, while adjusting the hardness of the wax to within to a desired range. The invention utilizes a synergistic effect between hard virgin Fischer-Tropsch wax and softer mildly isomerized Fischer-Tropsch wax in a blending process which allows the artisan to adjust the hardness of a wax product to within desired ranges. The process involves passing a Fischer-Tropsch wax over a hydroisomerization catalyst under predetermined conditions including relatively mild temperatures such that chemical conversions (e.g., hydrogenation and mild isomerization) take place while less than 10% boiling point conversion (hydrocracking) occurs, thus preserving overall isomerized wax yield.
    Type: Grant
    Filed: April 4, 2000
    Date of Patent: February 24, 2004
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Robert J. Wittenbrink, Daniel Francis Ryan
  • Patent number: 6696502
    Abstract: Fresh catalyst particles are added to a slurry hydrocarbon synthesis reactor and their activity increased by contact with hydrogen in-situ in the slurry in a catalyst activity increasing means, while the reactor is producing hydrocarbons. The means may be a simple, vertically oriented and hollow tube, open at the top and bottom, into which slurry and a hydrogen treat gas are passed. The treat gas acts as a lift gas which provides slurry circulation into and out of the means and back into the slurry body, while increasing the activity of the catalyst particles. During the activity increase of the fresh catalyst, partially and reversibly activated catalyst particles are rejuvenated. The activity increasing means may be inside the reactor and at least partially immersed in the slurry or external of the reactor, or both.
    Type: Grant
    Filed: June 2, 2000
    Date of Patent: February 24, 2004
    Assignee: ExxonMobil Research and Engineering Company
    Inventors: Charles John Mart, Daniel Ray Neskora