Patents by Inventor Zbigniew Twardowski

Zbigniew Twardowski 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 arsenic from acids
    Patent number: 4692228
    Abstract: Dissolved arsenic (III) contaminant is removed from mineral acids, such as hydrochloric acid, by electrolysis using a high surface area cathode having a three-dimensional electrolyte-contacting surface which exposes the electrolyte to electrolysis for a relatively long period of time. The dissolved arsenic is reduced to arsenic metal, which then plates out on the cathode. Dissolved concentrations of arsenic of less than 1 ppm can be achieved using the invention.
    Type: Grant
    Filed: May 21, 1986
    Date of Patent: September 8, 1987
    Assignee: Tenneco Canada Inc. (ERCO division)
    Inventor: Zbigniew Twardowski
  • Membrane pervaporation process
    Patent number: 4683039
    Abstract: Chlorine dioxide is transferred by membrane pervaporation from one chamber filled with aqueous chlorine dioxide-generating reactants or other chlorine dioxide donor medium across a gas-permeable hydrophobic membrane to a recipient aqueous medium filling a second chamber. The recipient medium may be water, pulp suspension or sodium chlorite solution. The membrane typically is expanded polytetrafluoroethylene.
    Type: Grant
    Filed: December 24, 1985
    Date of Patent: July 28, 1987
    Assignee: Tenneco Canada Inc. (ERCO division)
    Inventors: Zbigniew Twardowski, James D. McGilvery
  • Acid recovery in clorine dioxide generation
    Patent number: 4678655
    Abstract: Effluent acid from a non-evaporating chlorine dioxide-generating process is subjected to diffusion-dialysis across an anion-exchange membrane to preferentially transfer sulphuric acid from the effluent acid stream to a recipient aqueous medium while sodium sulphate remains in a waste stream. The sulphuric acid extracted from the effluent acid stream on this way may be recycled to the chlorine dioxide generator, after concentration, if desired.
    Type: Grant
    Filed: August 1, 1984
    Date of Patent: July 7, 1987
    Assignee: ERCO Industries Limited
    Inventor: Zbigniew Twardowski