Patents by Inventor John Hessler

John Hessler 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: 11130098
    Abstract: The invention is an improved method of making a carbon molecular sieve (CMS) membrane in which a precursor polymer is pyrolyzed to form a carbon molecular sieve membrane that is then exposed to a conditioning atmosphere comprised of a target permeate gas molecule such as ethylene when the membrane is desired to separate it from a light hydrocarbon gas stream. The exposure to the ethylene desirably occurs prior to the CMS permeance and selectivity combination substantially changing (e.g., within 5 days) of cooling from the pyrolyzing temperature. The CMS membranes have shown an improved combination of selectivity and permeance as well as stability and are useful to separate gases in gas streams such methane from natural gas, oxygen from air and ethylene or propylene from light hydrocarbon streams.
    Type: Grant
    Filed: November 30, 2016
    Date of Patent: September 28, 2021
    Assignee: Dow Global Technologies LLC
    Inventors: John Hessler, William J. Koros, Liren Xu, Mark K. Brayden, Marcos V. Martinez
  • Patent number: 11084000
    Abstract: The invention is an improved method of making a carbon molecular sieve (CMS) membrane in which a polyimide precursor polymer is pyrolyzed to form a carbon molecular sieve membrane by heating, in a furnace, said polyimide precursor polymer to a final pyrolysis temperature of 600 C to 700 C at a pyrolysis heating rate of 3 to 7 C/minute from 400 C to the final pyrolysis temperature, the final pyrolysis temperature being held for a pyrolysis time of at most 60 minutes in a non-oxidizing atmosphere. In a particular embodiment, the cooling rate from the pyrolysis temperature is accelerated by methods to remove heat. The CMS membranes have shown an improved combination of selectivity and permeance as well as being particularly suitable to separate gases in gas streams such methane from natural gas, oxygen from air and ethylene or propylene from light hydrocarbon streams.
    Type: Grant
    Filed: March 2, 2017
    Date of Patent: August 10, 2021
    Assignees: Dow Global Technologies LLC, Georgia Tech Research Corporation
    Inventors: John Hessler, William J. Koros, Liren Xu, Mark K. Brayden, Marcos V. Martinez
  • Publication number: 20190099722
    Abstract: The invention is an improved method of making a carbon molecular sieve (CMS) membrane in which a polyimide precursor polymer is pyrolyzed to form a carbon molecular sieve membrane by heating, in a furnace, said polyimide precursor polymer to a final pyrolysis temperature of 600 C to 700 C at a pyrolysis heating rate of 3 to 7 C/minute from 400 C to the final pyrolysis temperature, the final pyrolysis temperature being held for a pyrolysis time of at most 60 minutes in a non-oxidizing atmosphere. In a particular embodiment, the cooling rate from the pyrolysis temperature is accelerated by methods to remove heat. The CMS membranes have shown an improved combination of selectivity and permeance as well as being particularly suitable to separate gases in gas streams such methane from natural gas, oxygen from air and ethylene or propylene from light hydrocarbon streams.
    Type: Application
    Filed: March 2, 2017
    Publication date: April 4, 2019
    Inventors: John Hessler, William J. Koros, Liren Xu, Mark K. Brayden, Marcos V. Martinez
  • Publication number: 20180369761
    Abstract: The invention is an improved method of making a carbon molecular sieve (CMS) membrane in which a precursor polymer is pyrolyzed to form a carbon molecular sieve membrane that is then exposed to a conditioning atmosphere comprised of a target permeate gas molecule such as ethylene when the membrane is desired to separate it from a light hydrocarbon gas stream. The exposure to the ethylene desirably occurs prior to the CMS permeance and selectivity combination substantially changing (e.g., within 5 days) of cooling from the pyrolyzing temperature. The CMS membranes have shown an improved combination of selectivity and permeance as well as stability and are useful to separate gases in gas streams such methane from natural gas, oxygen from air and ethylene or propylene from light hydrocarbon streams.
    Type: Application
    Filed: November 30, 2016
    Publication date: December 27, 2018
    Inventors: John Hessler, William J. Koros, Liren Xu, Mark K. Brayden, Marcos V. Martinez
  • Patent number: 5254806
    Abstract: A magnet wire of modified cross-section is electrically insulated by adhering thereto an insulation tape which does not require a high temperature adherance step. The insulation tape has a pressure-sensitive adhesive coating which, prior to application to the magnet wire, is covered by a release strip. Just prior to application of the insulation tape to the magnet wire, the release strip is removed from the tape to uncover the adhesive coating and allow pressure-sensitive bonding of the insulation tape to the magnet wire.
    Type: Grant
    Filed: December 2, 1991
    Date of Patent: October 19, 1993
    Assignee: General Electric Co.
    Inventors: Steven Gross, John Hessler