Patents by Inventor Jean A. Andre

Jean A. Andre 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).

  • Process for the leaching of sulphides containing zinc and iron
    Patent number: 4676828
    Abstract: The extraction of zinc and copper and the recovery of precious metals from sulphurous zinciferous materials, also containing iron, becomes possible when these are treated by leaching under pressure in two stages, by judiciously controlling the relative quantities of sulphurous materials and acid.
    Type: Grant
    Filed: May 24, 1985
    Date of Patent: June 30, 1987
    Assignee: Societe des Mines et Fonderies de la Vieille Montagne
    Inventor: Jean A. Andre