Patents Assigned to Carbovan Inc.
  • Patent number: 4966761
    Abstract: A process is described for recovering vanadium and zeolitic alumino-silicates from flyash and similar carbon-bearing heat treated materials. The process includes steps for the separation of carbon, followed by pressure leaching the carbon-depleted flyash in relatively dilute alkali metal hydroxide solutions at elevated temperatures. The leach liquor is separated from the residue and is subsequently treated in an amine containing solvent extraction process step for vanadium recovery, and optionally, for other metals present in the leach liquor. The vanadium in the strip liquor is precipitated to obtain vanadium containing compounds.The leach residue is treated separately to recover zeolitic alumino-silicates therefrom.In another variation of the process, the vanadium is recovered from the leach liquor by means of a strong base anoin exchange resin.
    Type: Grant
    Filed: July 14, 1988
    Date of Patent: October 30, 1990
    Assignee: Carbovan Inc.
    Inventors: Vaikuntam I. Lakshmanan, Dzinsars Melnbardis, Robert A. Geisler, Nairn M. McQueen
  • Patent number: 4798709
    Abstract: A process is described for recovering vanadium and zeolitic alumino-silicates from flyash and similar carbon-bearing heat treated materials. The process includes steps for the separation of carbon, followed by pressure leaching the carbon-depleted flyash in relatively dilute alkali metal hydroxide solutions at elevated temperatures. The leach liquor is separated from the residue and is subsequently treated in an amine containing solvent extraction process step for vanadium recovery, and optionally, for other metals present in the leach liquor. The vanadium in the strip liquor is precipitated to obtain vanadium containing compounds.The leach residue is treated separately to recover zeolitic alumino-silicates therefrom.
    Type: Grant
    Filed: June 8, 1987
    Date of Patent: January 17, 1989
    Assignee: Carbovan Inc.
    Inventors: Vaikuntam I. Lakshmanan, Dzinsars Melnbardis, Robert A. Geisler