Patents Assigned to Yukong Limited
  • Patent number: 5580442
    Abstract: A process is disclosed for producing feedstocks for manufacturing high quality lube base oil utilizing unconverted oil, which is produced from a fuels hydrocracker unit. The first step of the process is the distillation of an atmospheric residue under vacuum in a first vacuum distillation unit to produce a vacuum gas oil. The vacuum gas oil is then hydrotreated in a first reaction unit to remove impurities and produce a treated vacuum gas oil. The treated vacuum gas oil is then subjected to hydrocracking in a second reaction unit to yield light hydrocarbons. The light hydrocarbons are then subjected to a series of fractional distillations to separate light oil products and an unconverted oil. All or a fraction of the unconverted oil is fed to a second vacuum distillation unit to produce feedstocks of high quality lube base oil and a remaining portion. The remaining portion and, optionally, a fraction of the unconverted oil is recycled from the second vacuum distillation unit to the second reaction unit.
    Type: Grant
    Filed: May 13, 1994
    Date of Patent: December 3, 1996
    Assignee: Yukong Limited
    Inventors: Sook-hyung Kwon, Wha-sik Min, Yun-kil Lee
  • Patent number: 5518893
    Abstract: The biochemical oxygen demand (BOD) of aqueous liquids containing organic matter is determined. A microorganism culture is aerated to exhaust the organic matter available to the microorganisms. An aqueous liquid test sample containing organic matter is added to the exhausted culture to measure the amount of oxygen consumed by the microorganisms. The determination of biochemical oxygen demand (BOD) of the sample is determined in as little as 20 minutes. An apparatus is provided for determining BOD comprising a magnetic stirrer, an aerating instrument, a dissolved oxygen/temperature sensor, tubing pumps and a quick biochemical oxygen demand (QBOD) bottle. The BOD may be automatically calculated using the apparatus.
    Type: Grant
    Filed: March 11, 1994
    Date of Patent: May 21, 1996
    Assignee: Yukong Limited
    Inventors: Yong-Seok Park, Hyung-Charn Kim, Sung-Hong Kim, Yong-Taek Yi
  • Patent number: 5510210
    Abstract: The present invention is directed to a solid electrolyte and a process for making the same for a sodium-sulfur secondary cell including a composition of 7.0 to 10.0 weight percent of Na.sub.2 O, 0.5 to 3.5 weight percent of MgO or 0.7 to 1.0 weight percent of Li.sub.2 O, 0.01 to 0.6 weight percent of WO.sub.3, and the balance of Al.sub.2 O.sub.3. The solid electrolyte is prepared by mixing Na.sub.2 O, MgO, Li.sub.2 O, WO.sub.3, and Al.sub.2 O.sub.3, calcining the resulting mixture, pulverizing the calcined body, and subjecting the resulting powders to sintering. Alternatively, the solid electrolyte is prepared by mixing Na.sub.2 O, MgO, or Li.sub.2 O, and Al.sub.2 O.sub.3 with one another, calcining the mixture, adding WO.sub.3 to the calcined body, pulverizing the resulting material, and subjecting the resulting powders to sintering.
    Type: Grant
    Filed: October 31, 1994
    Date of Patent: April 23, 1996
    Assignee: Yukong Limited
    Inventor: Young-shol Kim
  • Patent number: 5503645
    Abstract: The present invention improves the low temperature flow property of a fuel oil having a boiling point of 120.degree.-150.degree. C. by adding a novel compound prepared by reacting pri-, sec- or tert-aliphatic amine containing alkyl group of 1-30 carbon atoms with 9,10-dihydroanthracene-9,10-endo-.alpha.,.beta.-succinic acid or anhydride thereof together with a polymer having ethylene structure and/or a terpolymer of dialkyl fumarate-vinyl ester-vinyl ether.
    Type: Grant
    Filed: May 23, 1994
    Date of Patent: April 2, 1996
    Assignee: Yukong Limited
    Inventors: Hyun-Jong Jung, Bon-Cheol Ku, Ki-Ho Lee, Jin-Soo Lee
  • Patent number: 5468263
    Abstract: The present invention relates to an alkylphenyl poly(oxyalkylene) polyamine acid ester fuel detergent effective for controlling deposit generated in an automobile engine, prepared by reacting polyamine and alkylphenyl poly(oxyalkylene) maleate derivative prepared by reaction of alkylphenyl poly(oxyalkylene) alcohol and maleic anhydride, through Michael reaction. A fuel detergent diluted solution comprising 5-70 wt % of said fuel detergent and an inert organic solvent, and a hydrocarbon fuel composition comprising thereof are prepared. The present invention does not use deadly toxic phosgene gas used in preparation of a deposit control additive for conventional polyether amine deposit control additive and prevents generation of amine salt to eliminate the process for removing amine salt.
    Type: Grant
    Filed: February 18, 1994
    Date of Patent: November 21, 1995
    Assignee: Yukong Limited
    Inventors: Hyun-jong Chung, Sang-chul Yim, Bon-chul Ku, Ho-young Guen, Duk-han Kim
  • Patent number: 5461094
    Abstract: The present invention relates to a biodegradable film prepared by chemical bonding of starch and polyethylene chains using polyethylene, which is polyolefin having the most widest general application, coupling agent such as maleic anhydride, methacrylic anhydride or maleimide which bonds with starch and polyethylene, and acid catalytic comonomer like acrylic acid and/or methacrylic acid and to a process for preparing thereof.The present invention was accomplished varying coupling agent such as maleic anhydride, methacrylic anhydride or maleimide at an amount of 0.01-10 weight %, acid catalytic comonomer such as acrylic acid and/or methacrylic acid at an amount of 0.01-10 weight % and radical initiator at an amount of 0.01 1.0 weight % based on the amount of polyethylene, and the reactive extrusion was appelied to lower the production cost by process simplification.There was no difference in tensile strength and tensile elongation of the prepared biodegradable films comprising up to 20 wt.
    Type: Grant
    Filed: November 23, 1993
    Date of Patent: October 24, 1995
    Assignee: Yukong Limited
    Inventors: Yong-deuk Yoo, Yong-wook Kim, Won-yung Cho
  • Patent number: 5461093
    Abstract: In the present invention, the lowering of physical properties is minimized by bonding matrix resin and starch chemically using a coupling agent in the presence of an organic acid catalyst, at the same time lowering of the production cost is achieved by simplyfing the process. In the prior arts, the problems associated with low physical properties caused by starch incorporation were approached only in terms of enhanced physical interacting strength between matrix resin and starch.The purposes of the present invention are to provide a biodegradable polyethylene composition chemically bonded with starch comprising 100 parts by weight of matrix resin, 5-400 parts by weight of biodegradable incorporating material, 0.01-10 parts by weight of coupling agent, 0.01-1.0 parts by weight of radical initiator, 0.01-5 parts by weight of Lewis acid catalyst, 0.01-10 parts by weight of autoxidizing agent and 0.01-10 parts by weight of plasticizer and to provide a process for preparing thereof.
    Type: Grant
    Filed: November 23, 1993
    Date of Patent: October 24, 1995
    Assignee: Yukong Limited
    Inventors: Yong-deuk Yoo, Yong-wook Kim, Won-yung Cho
  • Patent number: 5239000
    Abstract: Thermoplastic elastomers in which low molecular weight ethylene/propylene/nonconjugated diene rubber ("liquid" EPDM rubber) replaces part of the high molecular weight EPDM rubber used in conventional blends exhibit better tension set properties than conventional blends in which liquid EPDM rubber is not used. A masterbatch containing liquid EPDM rubber and phenolic curing resin which is added to a mixture of polyolefin, high molecular weight EPDM rubber, and other ingredients during mixing results in a thermoplastic elastomer having better mechanical properties as well as better tension set properties than blends of conventional materials.
    Type: Grant
    Filed: June 21, 1991
    Date of Patent: August 24, 1993
    Assignee: Yukong Limited
    Inventors: Myung H. Kim, Byung H. Lee
  • Patent number: 5171881
    Abstract: It is a process for producing trimellitic acid (trimellitic acid, 1, 2, 4-tricarboxylic acid) by oxidizing pseudocumene with a molecular oxygen containing gas. More particularly, pseudocumene is oxidized into trimellitic acid by introducing a molecular oxygen containing gas in an acetic acid solvent in the presence of oxidizing catalysts, wherein the oxidization reactions in two different stages which have different ranges of temperature and different compositions of catalyst, respectively.
    Type: Grant
    Filed: November 29, 1990
    Date of Patent: December 15, 1992
    Assignee: Yukong Limited
    Inventors: Sang H. Park, Jae S. Go, Jung W. Sim, Chun G. Kim