Patents Represented by Attorney Daniel R. Head & Johnson Alexander
  • Patent number: 5474668
    Abstract: A process for dewaxing including the steps of mixing a waxy feedstock near its pour point with an ambient or below ambient temperature solvent essentially free of a selected cosolvent, to form a solvent/feedstock mixture, essentially free of a selected cosolvent, and subsequently adding the cosolvent to the solvent/feedstock mixture to cause instantaneous precipitation of wax on addition of cosolvent with the amount of wax precipitation being controlled by the quantity and temperature of cosolvent added. The cosolvent is essentially completely miscible with the solvent, but immiscible with the oil and wax. For example, alcohols (methanol, ethanol, propanol), ketones (ketene, acetone), amines, etc. The process of the present invention provides the advantages of lower solvent ratios (higher solvent recovery), higher filtration temperatures, "environmentally compatible" solvents, rapid filtration rates, and debottlenecking of existing dewaxing plants.
    Type: Grant
    Filed: July 25, 1994
    Date of Patent: December 12, 1995
    Assignees: University of Arkansas, Advanced Refining Technologies, Inc.
    Inventors: Michael D. Ackerson, Seyed-Hamid Arabshahi, Robert E. Babcock
  • Patent number: D365139
    Type: Grant
    Filed: October 4, 1993
    Date of Patent: December 12, 1995
    Inventor: Lynn Gibbins