Patents by Inventor Peter R. Drew

Peter R. Drew 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).

  • Electrolytic metal recovery
    Patent number: 4762598
    Abstract: Electrolytic recovery of silver metal is accomplished by application of a direct current with controlled ripple such that for any concentration of silver in the electrolyte, the instantaneous magnitude of the electrical potential across the electrodes is sufficient to sustain deposition of silver on the cathode while the peak values of said electrical potential are below the critical potential at and above which silver sulphide is precipitated from solution and/or hydrogen sulphide gas is generated.
    Type: Grant
    Filed: January 12, 1987
    Date of Patent: August 9, 1988
    Inventor: Peter R. Drew