Patents by Inventor John A. Jensvold

John A. Jensvold 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: 6153097
    Abstract: A gas separation membrane device comprising an internally staged permeator containing a three dimensional array of hollow fiber membranes grouped into multiple sets in intimate contact with each other is described. The incorporation of the internally staged permeator, particularly, the arrangement of the multiple sets of fiber membranes in intimate contact with each other, results in improved efficiency of the device, especially for feed streams or membrane types that lead to high permeate flow rate that result in excessive shellside pressure drops.
    Type: Grant
    Filed: May 26, 1999
    Date of Patent: November 28, 2000
    Assignees: MG Generon, University of Toledo
    Inventors: John Jensvold, Glenn Lipscomb
  • Patent number: 5598874
    Abstract: Hollow fiber membrane modules are manufactured by weaving hollow fiber membranes into a web while the fibers still contain a residual amount of the organic liquids used in the extrusion of the fibers. The web once formed is then passed through a final solvent extraction stage, followed by drying and heating to fix the final form and permeation characteristics of the membranes, and finally rolling the web into a bundle which forms the interior of the module. The hollow fibers are woven as fill in the web.
    Type: Grant
    Filed: August 11, 1995
    Date of Patent: February 4, 1997
    Assignee: MG Generon, Inc.
    Inventors: Philip E. Alei, Jeff C. Schletz, John A. Jensvold, Ward E. Tegrotenhuis, Wickham Allen, Frederick L. Coan, Karen L. Skala, Daniel O. Clark, Harold V. Wait, Jr.
  • Patent number: 5409524
    Abstract: The invention is a process for obtaining membranes having improved selectivity and recovery using a combination of heat treating and UV irradiation.
    Type: Grant
    Filed: September 10, 1993
    Date of Patent: April 25, 1995
    Assignee: The Dow Chemical Company
    Inventors: John A. Jensvold, Srikanth R. Chary, Wendy S. Jacks, Hans R. Keller, Theodore L. Parker, Damoder Reddy
  • Patent number: 5282964
    Abstract: The present invention is a bore-fed hollow fiber membrane device which possesses improved shellside countercurrent flow distribution. More specifically, the hollow fiber membrane bundle has a radial Peclet number of about 30 or lower which results in improved fluid recovery and productivity.
    Type: Grant
    Filed: February 19, 1993
    Date of Patent: February 1, 1994
    Assignee: The Dow Chemical Company
    Inventors: Thomas C. Young, Terrence L. Caskey, Johnny L. Trimmer, George E. Mahley, III, Randall A. Yoshisato, John A. Jensvold
  • Patent number: 5163977
    Abstract: The invention is a semi-permeable gas separation membrane containing a non-ionic surfactant and which possesses improved resistance to thermal compaction or aging. The invention includes a process for making such membranes as well as a method of using such membranes.
    Type: Grant
    Filed: August 22, 1991
    Date of Patent: November 17, 1992
    Assignee: The Dow Chemical Company
    Inventors: John A. Jensvold, Tsungnan Cheng, Donald L. Schmidt
  • Patent number: 5141530
    Abstract: The invention is a semi-permeable gas separation membrane having disposed thereon a non-ionic surfactant. The membrane possesses improved selectivity and recovery. The invention includes a process for making such membranes as well as a method of using such membranes.
    Type: Grant
    Filed: August 22, 1991
    Date of Patent: August 25, 1992
    Assignee: The Dow Chemical Company
    Inventors: John A. Jensvold, Tsungnan Cheng, Donald L. Schmidt
  • Patent number: 4955993
    Abstract: The invention is a semi-permeable hollow fiber gas separation membrane possessing a non-external discriminating region fabricated from hydrophobic polymeric materials possessing less than about 1 weight percent equilibrium water content at about 25.degree. C. The invention includes a process for making such membranes as well as a method of using such membranes.
    Type: Grant
    Filed: July 31, 1989
    Date of Patent: September 11, 1990
    Assignee: The Dow Chemical Company
    Inventors: Edgar S. Sanders, Jr., John A. Jensvold, Daniel O. Clark, Frederick L. Coan, Henry N. Beck, William E. Mickols, Peter K. Kim, Wudneh Admassu
  • Patent number: 4900334
    Abstract: This invention relates to a method of treating liquid-wet polycarbonate membranes to improve gas separation properties.
    Type: Grant
    Filed: November 9, 1988
    Date of Patent: February 13, 1990
    Assignee: The Dow Chemical Company
    Inventors: Wudneh Admassu, John A. Jensvold, Daniel O. clark
  • Patent number: 4838904
    Abstract: The invention is a semi-permeable membrane which comprises a polymeric matrix with two porous surfaces and a region which functions to separate one or more gases from one or more other gases.The membranes of this invention exhibit excellent separation factors and flux. Such membranes are less prone to being damaged due to handling and exposure to contaminants due to the internal region which affects the separation, as the porous surfaces function to protect such region.
    Type: Grant
    Filed: December 7, 1987
    Date of Patent: June 13, 1989
    Assignee: The Dow Chemical Company
    Inventors: Edgar S. Sanders, Jr., Daniel O. Clark, John A. Jensvold
  • Patent number: 4772392
    Abstract: The invention is a process for the preparation of a POWADIR membrane comprising bisphenol-based polycarbonates wherein at least 25 percent by weight of the bisphenol moieties are tetrahalogenated wherein the halogen is Cl or Br, and the membrane prepared by such process.
    Type: Grant
    Filed: November 6, 1987
    Date of Patent: September 20, 1988
    Assignee: The Dow Chemical Company
    Inventors: Edgar S. Sanders, Jr., Daniel O. Clark, John A. Jensvold, Henry N. Beck, G. Glenn Lipscomb, II, Frederick L. Coan