Title:
METHOD FOR ELECTROCHEMICALLY RECOVERING HEAVY METAL FROM FLY ASH
Document Type and Number:
Japanese Patent JP3951041
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a method capable of efficiently and easily recovering various kinds of metals from the incineration fly ash produced when wastes of shredder dust, or the like, are incinerated or the molten fly ash produced when the incineration fly ash is further melted by a plasma, or the like.
SOLUTION: An aqueous sulfuric acid solution of a pH ≤4 is subjected to extraction treatment to elute copper, cadmium and zinc in this solution. An electrolysis is effected between an anode and a cathode in the separated solution obtained by the separation of solid from liquid of a fly ash-containing slurry. The cathode potential is gradually or stepwise changed in a negative direction, by which the copper, cadmium and zinc are discriminated and electrolytically deposited on the cathode. The residue remaining after the separation of the solid from the liquid is thereafter subjected to the extraction treatment with an aqueous sodium thiosulfate solution to elute lead in this solution. A DC electric power is applied between the anode and the cathode in the separated solution obtained by the separation of the solid from liquid of the residue containing slurry, by which the lead in the solution is settled as lead sulfide.
Inventors:
Inazumi
Atsushi Yano
Masayoshi Kondo
Hiroshi Tatsumi
Atsushi Yano
Masayoshi Kondo
Hiroshi Tatsumi
Application Number:
JP2001219262A
Publication Date:
August 01, 2007
Filing Date:
July 19, 2001
Export Citation:
Assignee:
Hitachi Zosen Corporation
International Classes:
B09B3/00; B01D11/02; C25C1/12; C02F1/461; C22B3/04; C22B15/00; C22B17/00; C22B19/00; C22B19/20; C25C1/16; C25C1/18; (IPC1-7): C25C1/12; B01D11/02; B09B3/00; C02F1/461; C25C1/16; C25C1/18; //C22B3/04; C22B15/00; C22B17/00; C22B19/00
Domestic Patent References:
JP11335748A | ||||
JP2000290736A | ||||
JP8035017A | ||||
JP10503552A |
Attorney, Agent or Firm:
Einosuke Kishimoto
Akira Watanabe
Norihiko Hibi
Kiyosue Yasuko
Akira Watanabe
Norihiko Hibi
Kiyosue Yasuko
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