Patents by Inventor Ulrich Haidlen

Ulrich Haidlen 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).

  • Patent number: 4587110
    Abstract: A process is described by which copper and optionally silver and gold are recovered from sulfide and oxide ores, concentrates or slag, which contain the metals. The particulate materials are treated with an aqueous solution of an alkali cyanide or alkaline earth cyanide, the laden solution is filtered, if desired, a water-soluble sulfide compound is added to the laden solution or filtered laden solution, the laden solution is subsequently adjusted to a pH value below 5 by an addition of acid to precipitate the metal sulfide, which is filtered off, and the resulting hydrocyanic acid is recovered. The process steps of precipitation and filtration of the metal sulfide and the recovery of the free hydrocyanic acid contained in the filtrate are carried out under superatmospheric pressure of 1.5 to 15 bars. The precipitation is preferably effected at a pH value of 1.5 to 2.0. The free hydrocyanic acid is recovered as alkali cyanide or alkaline earth cyanide and is recirculated to the leaching stage.
    Type: Grant
    Filed: August 8, 1984
    Date of Patent: May 6, 1986
    Assignee: MNR Reprossesing, Inc.
    Inventors: George M. Potter, Arthur Bergmann, Ulrich Haidlen