Patents Examined by John Poll
  • Metal scavenger and metal scavenging process
    Patent number: 4670160
    Abstract: A metal scavenger is composed of an addition product of a polyamine and an epihalohydrin. The addition product contains as substituent or substituents at least one carbodithio group and/or at least one carbodithioate salt group introduced therein by substituting the corresponding number of active hydrogen atom or atoms in the addition product. Metals can be scavenged from waste water by adding the metal scavenger together with at least one of sodium monosulfide, sodium polysulfides and sodium hydrogensulfide.
    Type: Grant
    Filed: September 11, 1986
    Date of Patent: June 2, 1987
    Assignee: Miyoshi Yushi Kabushiki Kaisha
    Inventors: Masafumi Moriya, Kazuo Hosoda, Akira Nishimura, Takao Imachi