Patents Assigned to Societe des Mines et Fonderies de la Vieille Montagne
  • 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