| 摘要 |
1481663 Electrowinning metals PAREL SA 6 Jan 1976 [9 Jan 1975] 1014/75 Heading C7B A metal e.g. Co, Ni, Cu, Mn, Zn, Fe, Au or Ag, is recovered from ore, matte, concentrate or alloy by electrowinning in an electrolytic cell 2 having an anode compartment 8, a cathode compartment 4 and at least one intermediate compartment 16, the boundaries between the compartments each including a separator 12, 14 permselective to at least one ionic species present in the or one of the intermediate compartment(s) bounded by the respective separator; the separator 12 contiguous with the cathode compartment is permselective to anions e.g. SO 4 <SP>--</SP>. An aqueous solution of at least one salt of the metal is circulated around a first circuit 20 including the cathode compartment 4 in which the metal is electro-deposited at the cathode 6, and an acid solution is circulated around a second circuit 24 including the anode compartment 8. As shown with a cell including a single intermediate compartment 16, both separators may be anion exchange membranes, e.g. for CoSO 4 , dilute acid solution being circulated around a third circuit 28 including the intermediate compartment 16, and acid produced in anode compartment being withdrawn from the second circuit and replaced by less acidic solution by adding water to the third, Fig. 1, or second circuit Fig. 2 (not shown); alternatively the separator 14 contiguous with the anode compartment is a cation exchange membrane Fig. 3 (not shown), e.g. for solutions made up from basic CoO precipitates, acid solution withdrawn from the third circuit being admixed with spent catholyte to form a mixture at least part of which is used to dissolve further metalliferous material for subsequent supply to the catholyte. Preferably the cathode is particulate comprising discrete conductive particles. |
