Isomerization Patents (Class 585/253)
  • Patent number: 4654452
    Abstract: A hexanes stream, conventionally produced in petroleum refining, comprising normal hexane, isohexanes, methylcyclopentane, and cyclohexane is isomerized to produce primarily cyclohexane and to recover normal hexane by first fractionating the hexanes stream in a first fractionation step in a manner and under conditions to produce a normal hexane-isohexane rich overhead stream and a methylcyclopentane-cyclohexane rich bottoms stream, the bottoms stream is isomerized in the presence of an isomerization catalyst and under conditions sufficient to maximize the conversion of methylcyclopentane to cyclohexane, the overhead from the first fractionation step and the effluent from the isomerization step is then fractionated in at least one stage of a second fractionation step in a manner and under conditions to produce separate streams, comprising isohexanes, normal hexane, cyclohexane, and unreacted methylcyclopentane and the methylcyclopentane is recycled to the isomerization step and/or the first fractionation step.
    Type: Grant
    Filed: December 16, 1982
    Date of Patent: March 31, 1987
    Assignee: Phillips Petroleum Company
    Inventors: William C. Rahlwes, Ralph G. Carrasco, Jr.
  • Patent number: 4625069
    Abstract: Coordination compounds of rhodium are solid salts having donor ligands of [(aryl).sub.3 P].sub.3 Rh.sup.+ and a non-coordinated counterion derived from a fluorochemical acid, the salts having the formula:[(aryl).sub.3 P].sub.3 Rh.sup.+ (counterion).sup.-.The salts are prepared by reacting [(aryl).sub.3 P].sub.4 RhH, which is and uncharged rhodium hydride, with a fluorochemical acid selected form acids having the formulae:HC(R)(SO.sub.2 R.sub.f).sub.2, R.sub.f 'SO.sub.3 H, and HN(SO.sub.2 R.sub.f).sub.2wherein R.sub.f and R.sub.f ' are perfluoroalkyl groups and R is lower alkyl substituted or unsubstituted phenyl, hydrogen, Cl, SO.sub.2 R.sub.f or R.sub.f. Carbonylation of the [(aryl).sub.3 P].sub.3 Rh.sup.+ (counterion).sup.- compounds of this invention, e.g., by contacting the salts of the invention with carbon monoxide gas, produces salts having the formula:[(aryl).sub.3 P].sub.3 Rh(CO).sub.n.sup.+(counterion).sup.-,wherein n is 1 or 2, and (counterion).sup.- is as defined above.
    Type: Grant
    Filed: August 26, 1985
    Date of Patent: November 25, 1986
    Assignee: Minnesota Mining and Manufacturing
    Inventors: Allen R. Siedle, Richard D. Howells
  • Patent number: 4507516
    Abstract: A fuel composition comprising a hydrogenated material obtained by hydrogenating a reaction mixture ranging from C.sub.11 to C.sub.16 containing mainly compounds which comprise butadiene and cyclopentadiene as basic structural units, produced by reacting an acyclic conjugated diene with cyclopentadiene, dicyclopentadiene, an alkyl-substituted cyclopentadiene, or an alkyl-substituted dicyclopentadiene in accordance with Diels-Alder reaction an isomeric material prepared by isomerizing the hydrogenated material or the mixture of the hydrogenated material and the isomeric material.
    Type: Grant
    Filed: March 14, 1984
    Date of Patent: March 26, 1985
    Assignee: Nippon Petrochemicals Co., Ltd.
    Inventors: Seiji Hirooka, Michiaki Torii
  • Patent number: 4427467
    Abstract: An improved ramjet fuel consisting of hydrogenated hydrocarbons uses a mium weight percentage of 50% tetrahydromethylcyclopentadiene dimer (TH-dimer) with about 50% by wt. exo-tetrahydrodicyclopentadiene (Exo-THDC). The mixture exceeds U.S. Navy flash point requirements of 60.degree. C. while yielding a lower viscosity than TH-dimer alone. Volumetric heating properties of the mixture make it an excellent ramjet fuel.
    Type: Grant
    Filed: April 29, 1982
    Date of Patent: January 24, 1984
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: George W. Burdette, Lewis Hall
  • Patent number: 4401837
    Abstract: A high density fuel for airbreathing or bi-propellant engines consisting of xo-tetrahydrotricyclopentadiene (EXO-THTC) alone and in mixtures with other high density fuels. Processes for their preparation are also disclosed.
    Type: Grant
    Filed: June 2, 1980
    Date of Patent: August 30, 1983
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: George W. Burdette, Abraham I. Schneider
  • Patent number: 4398978
    Abstract: A method for preparation of high density, high energy, low viscosity liquid ydrocarbon fuel by catalytic treatment of tetrahydrodimethyldicyclopentadiene (RJ-4) synthetic fuel. Endo-isomers within the fuel stock are isomerized to exo-isomers by treatment of the fuel stock with catalysts such as aluminum chloride, nickel, or pulverized, acid treated firebrick resulting in a fuel having a lower viscosity than the original RJ-4.
    Type: Grant
    Filed: April 26, 1982
    Date of Patent: August 16, 1983
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: George W. Burdette, Abraham I. Schneider
  • Patent number: 4328385
    Abstract: Isomerizable hydrocarbons are isomerized using a catalytic composite comprising a combination of a catalytically effective amount of a pyrolyzed rhenium carbonyl component with a porous carrier material containing a uniform dispersion of catalytically effective amounts of a platinum group component, which is maintained in the elemental metallic state during the incorporation and pyrolysis of the rhenium carbonyl component, of a tin component, and of a halogen component.
    Type: Grant
    Filed: December 3, 1980
    Date of Patent: May 4, 1982
    Assignee: UOP Inc.
    Inventor: George J. Antos
  • Patent number: 4320238
    Abstract: A high density fuel composition having low temperature operational capability for propelling turbo-jet, limited volume missile systems consisting essentially of at least 95 weight percent exo-tetrahydrodicyclopentadiene (JP-10) and a correspondingly minor amount of a C.sub.3 -C.sub.7 saturated hydrocarbon.
    Type: Grant
    Filed: August 21, 1980
    Date of Patent: March 16, 1982
    Assignee: Ashland Oil, Inc.
    Inventors: Richard V. Norton, Steven C. Howe
  • Patent number: 4286109
    Abstract: A high density specialty fuel for propelling limited volume ramjet and turbojet missile systems comprising a blend of at least 70 weight percent of exotetrahydrodicyclopentadiene and a correspondingly minor amount of a combination of a C.sub.5 -C.sub.7 alkane or cycloalkane and a tetrahydro derivative of the trimer and/or co-trimer of cyclopentadiene and methylcyclopentadiene.
    Type: Grant
    Filed: July 31, 1980
    Date of Patent: August 25, 1981
    Assignee: Ashland Oil, Inc.
    Inventors: Richard V. Norton, Dennis H. Fisher
  • Patent number: 4277636
    Abstract: Method for effecting the formation of co-trimers of cyclopentadiene and methylcyclopentadiene whereby a mixture of the dimers of said dienes is heated in the presence of an inert solvent. The foregoing method is implemented to provide a high energy fuel by substantially completely hydrogenating the resultant trimerization product.
    Type: Grant
    Filed: August 11, 1980
    Date of Patent: July 7, 1981
    Assignee: Ashland Oil, Inc.
    Inventors: Richard V. Norton, Peter J. Frank, Dennis H. Fisher, Steven C. Howe
  • Patent number: 4270014
    Abstract: A method for converting endo-tetrahydrodicyclopentadiene to the corresponding exo isomeric form which is advantageously carried out in the presence of aluminum chloride catalyst and the spent nickel hydrogenation catalyst utilized in hydrogenating an endo dimer of cyclopentadiene to provide said tetrahydro derivative thereof.
    Type: Grant
    Filed: April 30, 1979
    Date of Patent: May 26, 1981
    Assignee: Ashland Oil, Inc.
    Inventors: Richard V. Norton, Steven C. Howe
  • Patent number: 4191845
    Abstract: Unsaturated C.sub.4 hydrocarbons are converted into normal butane by introducing an unsaturated C.sub.4 hydrocarbon stream into a hydrogenation zone to convert it into a stream of normal butane and isobutane. Normal butane is recovered from a separation zone while isobutane is directed to an isomerization zone wherein a portion of the isobutane is converted into normal butane. The stream from the isomerization zone is returned to the separation zone to recover the normal butane produced in the isomerization reaction. The normal butane produced by the process is subsequently utilized in a cracking zone to produce ethylene.
    Type: Grant
    Filed: July 25, 1978
    Date of Patent: March 4, 1980
    Assignee: Stone & Webster Engineering Corporation
    Inventors: Jacob N. Rubin, Frederick B. Seufert
  • Patent number: 4177217
    Abstract: Dimethyldicyclopentadiene is continuously hydrogenated to tetrahydrodimethyldicyclopentadiene and then the latter is continuously isomerized to a missile fuel. Both the hydrogenation and the isomerization steps use a nickel on silica-alumina catalyst. The temperature of the hydrogenation is in the range of about 70.degree.-260.degree. C., and the temperature of the isomerization is in the range of about 200.degree.-280.degree. C. The space velocity of the hydrogenation is about 0.1 to about 2.0 volumes of the diene charged per volume of catalyst per hour and the space velocity of the isomerization is about 0.1 to about 3.0 volumes of the hydrocarbon charged per volume of catalyst per hour. The pressure range for hydrogenation is between about 200 psig to about 3000 psig and for isomerization between from about 10 psig to about 1500 psig. Hydrogen is present during the isomerization.
    Type: Grant
    Filed: September 28, 1977
    Date of Patent: December 4, 1979
    Assignee: Suntech, Inc.
    Inventors: Edward J. Janoski, Richard E. Mitchell, Abraham Schneider