Patents by Inventor Stephen L. Dickman

Stephen L. Dickman 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).

  • Cement compositions and biodegradable dispersants therefor
    Patent number: 6019835
    Abstract: This invention provides improved cement composition and biodegradable dispersants therefor. The biodegradable dispersants are basically comprised of a high molecular weight, phenolic hydroxy group blocked, alkali metal lignosulfonate.
    Type: Grant
    Filed: September 1, 1998
    Date of Patent: February 1, 2000
    Assignees: Halliburton Energy Services, Inc., LignoTech U.S.A., Inc.
    Inventors: Jiten Chatterji, D. Chad Brenneis, Dennis W. Gray, Stuart E. Lebo, Stephen L. Dickman
  • Production of oxidized humic acids by an oxygen-alkali process
    Patent number: 5688999
    Abstract: A method is disclosed for the production of oxidized humic acids. The process of the invention comprises reacting humic acid bearing ores with oxygen under alkaline conditions at a temperature between 100.degree. C. and 200.degree. C. for at least 1/2 hour, but usually for 1-2 hours, to produce oxidized humic acids which are soluble at pH as low as 2.9 and which are formed in yields of at least 70%. The oxidized humic acids produced according to the process of the invention are also superior viscosity reducers.
    Type: Grant
    Filed: January 26, 1996
    Date of Patent: November 18, 1997
    Assignee: Lignotech USA, Inc.
    Inventors: Stuart E. Lebo, Jr., Kevin R. Wirtz, Stephen L. Dickman