Selective separation of cobalt, nickel or cadmium - from chlorinated zinc solns. using elementary sulphur and metallic zinc

摘要

Selective sepn. of Co, Ni and/or Cd and other metals more noble than Zn is effected by S cementation from chlorided Zn solns. Zn metal and elementary S are added in finely divided form at high temp. to the solns., the suspension is stirred for a long time and the pptd. metals are separated from the Zn soln. The S can be replaced totally or partially by reactive sulphides, e.g. ZnS or FeS. The cemented metals are totally or partially converted into sulphides by the action of elementary S, H2S formed intermediately or by the appropriate sulphides. Co, Ni, Cd, Ag, Cu, Pb and/or As can be pptd. from chlorided Zn solns.