Patents by Inventor Stewart H. Presnall

Stewart H. Presnall 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).

  • Removal of aromatic color bodies from aromatic hydrocarbon streams
    Patent number: 5207894
    Abstract: This invention provides a process to remove aromatic color bodies, particularly oxygen or sulfur containing aromatics from a C.sub.8-11 aromatic hydrocarbon stream having a boiling range between about 160.degree.-460.degree. F. The process involves contacting the hydrocarbon stream with a neutral attapulgite clay for a time sufficient to adsorb the aromatic color bodies. The process is effective in reducing the APHA color value of the subject hydrocarbon stream from an initial 850-1100 value to about 400 or less.
    Type: Grant
    Filed: October 11, 1991
    Date of Patent: May 4, 1993
    Assignee: Lyondell Petrochemical Company
    Inventors: Stewart H. Presnall, Robert J. Haynal, Beverly B. Slimp, Jr., Martin P. Grosboll, Pamela A. Yanchik
  • Purification of unsaturated hydrocarbon streams containing styrenics
    Patent number: 5081325
    Abstract: This invention relates to a method for removing polar bodies and other contaminants, including color bodies, from unsaturated hydrocarbon streams having a boiling range between 280.degree.-310.degree. F. by contacting the unsaturated hydrocarbon stream with a neutral clay comprising an oxide state of at least one and preferably two of Si, Al, Fe, Ca, Mg, K, Na, S, and P, particularly attapulgite clay. The process is most effective if the unsaturated hydrocarbon stream is first dried using a molecular sieve.
    Type: Grant
    Filed: October 12, 1990
    Date of Patent: January 14, 1992
    Assignee: Lyondell Petrochemical Company
    Inventors: Robert J. Haynal, Stewart H. Presnall, Beverly B. Slimp, Jr.
  • Manufacture of disulfides
    Patent number: 4868336
    Abstract: A method for preparing disulfides comprising combining at least one mercaptan of the general formula R-SH wherein R is selected from the group consisting of an alkyl, aryl, aralkyl, cycloalkyl, arylcycloalkyl radical, and mixtures thereof; at least one oxidizing agent; at least one aqueous base; at least one oxygen containing water miscible organic compound; and at least one divalent transition metal carboxylic acid salt and/or divalent transition metal sulfate salt.
    Type: Grant
    Filed: November 20, 1987
    Date of Patent: September 19, 1989
    Assignee: Phillips Petroleum Company
    Inventor: Stewart H. Presnall