Patents by Inventor Biddanda U. Achia

Biddanda U. Achia has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5306681
    Abstract: The isomerization activity of hydroisomerization catalyst is recovered by subjecting the catalyst to a wash using light aromatic solvents at elevated temperature, e.g. toluene at 300.degree. C. This hot aromatic solvent wash may be preceded by a hot hydrogen containing gas strip. Catalyst activity can be maintained by the continuous or periodic addition of light aromatic solvent or light aromatic containing materials to the feeds sent to the isomerization catalyst.
    Type: Grant
    Filed: March 26, 1993
    Date of Patent: April 26, 1994
    Assignee: Exxon Research and Engineering Company
    Inventors: James J. Schorfheide, Biddanda U. Achia
  • Patent number: 5212128
    Abstract: The isomerization activity of hydroisomerization catalyst is recovered by subjecting the catalyst to a wash using light aromatic solvents at elevated temperature, e.g. toluene at 300.degree. C. This hot aromatic solvent wash may be preceded by a hot hydrogen containing gas strip. Catalyst activity can be maintained by the continuous or periodic addition of light aromatic solvent or light aromatic containing materials to the feeds sent to the isomerization catalyst.
    Type: Grant
    Filed: November 29, 1991
    Date of Patent: May 18, 1993
    Assignee: Exxon Research & Engineering Company
    Inventors: James J. Schorfheide, Biddanda U. Achia
  • Patent number: 5059299
    Abstract: Slack waxes and synthetic wax are isomerized and processed into high viscosity index and very low pour point lube base stock oils and blending stocks by the process comprising the steps of hydrotreating the wax, if necessary, to remove heteroatom and polynuclear aromatic compounds and/or deoiling the wax, if necessary, to an oil content between about 5-20% oil, isomerizing the wax over a Group VI-Group VIII on halogenated refractory metal oxide support catalyst, said isomerization being conducted to a level of conversion such that .about.40% and less unconverted wax remains in the 330.degree. C..sup.+, preferably the 370.degree. C..sup.+ fraction sent to the dewaxer. The total isomerate from the isomerization unit is fractionated into a lube oil fraction boiling at 330.degree. C..sup.+, preferably 370.degree.p9 C..sup.+. This oil fraction is solvent dewaxed preferably using MEK/MIBK at 20/80 ratio and unconverted wax is recycled to the isomerization unit.
    Type: Grant
    Filed: May 11, 1990
    Date of Patent: October 22, 1991
    Assignee: Exxon Research and Engineering Company
    Inventors: Ian A. Cody, James D. Bell, Theodore H. West, William A. Wachter, Biddanda U. Achia
  • Patent number: 4937399
    Abstract: The present invention is directed to a process for the catalytic isomerization of waxes to liquid products, particularly to the production of high yields of liquid products boiling in the 370.degree. C..sup.+ range suitable for use as lube oil base stocks or blending stocks, said process employing as the catalyst a material made by depositing a hydrogenation metal component on a refractory metal oxide base, preferably alumina, fluoriding said metal loaded base using aqueous HF and subsequently crushing the fluorided metal loaded base to produce a sized material of 1/32 inch and less its largest cross-sectional dimension. Alternately the catalyst can be made by depositing a hydrogenation metal component on a refractory metal oxide base of 1/32 inch and less across its largest cross-sectional dimension and subsequently fluoriding said sized material using aqueous HF. In either case the catalyst is activated before being used by heating in a hydrogen atmosphere to from 350.degree. C. to 500.degree. C.
    Type: Grant
    Filed: December 13, 1988
    Date of Patent: June 26, 1990
    Assignee: Exxon Research and Engineering Company
    Inventors: William A. Wachter, Ian A. Cody, Glen P. Hamner, deceased, Biddanda U. Achia
  • Patent number: 4673485
    Abstract: A process in fuels production for increasing the yield of deasphalted oil production from upgraded residua and improving deasphalter operability involving mixing the upgraded residua with an aromatics solubilizing aid to prevent the formation of an immiscible third phase during deasphalting.
    Type: Grant
    Filed: April 6, 1984
    Date of Patent: June 16, 1987
    Assignee: Exxon Research and Engineering Company
    Inventors: Duncan J. Bristow, Biddanda U. Achia, Lawrence J. Evers
  • Patent number: 4594142
    Abstract: A solvent dewaxing process is described comprising mixing a waxy hydrocarbon oil, preferably a waxy petroleum oil, most preferably a waxy lube or specialties oil, with dewaxing solvent and a dewaxing aid comprising (A) a dialkylfumarate-vinyl laurate copolymer and (B) a wax-naphthalene condensation copolymer, a dialkyl fumarate-vinyl acetate copolymer or an ethylene vinyl acetate copolymer and chilling the mixture to yield a slurry comprising solid particles of precipitated wax and a solution of dewaxed oil and solvent and separating said solid wax from dewaxed oil solution.
    Type: Grant
    Filed: April 25, 1985
    Date of Patent: June 10, 1986
    Assignee: Exxon Research and Engineering Co.
    Inventors: Biddanda U. Achia, Abraham R. DeKraker, Albert Rossi
  • Patent number: 4592832
    Abstract: A process for increasing the production of Bright Stock oil in a lube oil process scheme. Aromatic extract oil, after being separated from the extraction solvent, is recycled back to the deasphalter unit and combined with a vacuum residuum in 10-20 LV %, based on the total deasphalter feed, prior to deasphalting. After deasphalting and aromatics extraction the absolute yield of raffinate is increased.
    Type: Grant
    Filed: September 6, 1984
    Date of Patent: June 3, 1986
    Assignee: Exxon Research and Engineering Co.
    Inventors: Duncan J. Bristow, Biddanda U. Achia, Lawrence J. Evers
  • Patent number: 4522710
    Abstract: A method for increasing the production of deasphalted oil is described. The method comprises passing a hydrocarbon feedstock into a first distillation zone wherein the feedstock is separated into a first distillate and a first residuum. First residuum is passed to a second distillation zone wherein the fraction is separated into a second distillate and a second residuum. Second distillate and residuum are passed to a deasphalting zone and contacted with a solvent to produce a deasphalted oil. This method may produce increased quantities of acceptable quality deasphalted oil where the deasphalting zone is rate-limiting.
    Type: Grant
    Filed: December 9, 1983
    Date of Patent: June 11, 1985
    Assignee: Exxon Research & Engineering Co.
    Inventors: Biddanda U. Achia, David H. Shaw, James D. Bushnell
  • Patent number: 4377467
    Abstract: An improved dewaxing aid for solvent dewaxing processes comprising a mixture of (a) lithium isostearate and (b) a polymer of an ester of at least one aliphatic alcohol with methacrylic acid or acrylic acid having an average molecular weight ranging from between about 300,000 to 2,000,000. The lithium isostearate, when combined with the acrylic polymer, synergistically improves the efficiency of wax separation. This has been found to be especially useful for dewaxing heavy petroleum oil fractions, such as bright stocks.
    Type: Grant
    Filed: January 30, 1981
    Date of Patent: March 22, 1983
    Assignee: Exxon Research and Engineering Co.
    Inventor: Biddanda U. Achia
  • Patent number: 4203824
    Abstract: Polyvinylpyrrolidone having a number average molecular weight ranging from about 150,000 to 400,000 has been found to be an effective dewaxing aid for bright stock in ketone dewaxing processes. Using as little as 100 ppm based on the waxy oil can result in almost a 50% increase in the filter rate of the dewaxed oils from the wax.
    Type: Grant
    Filed: December 22, 1978
    Date of Patent: May 20, 1980
    Assignee: Exxon Research & Engineering Co.
    Inventors: Biddanda U. Achia, David H. Shaw