| 摘要 |
<p>1355535 Extracting metal values UNIVERSITY OF MELBOURNE 28 May 1971 [28 May 1970 17 June 1970] 18137/71 Heading C1A [Also in Divisions C2 and C7] Metal values are extracted from solution by contact with brown coal, brown coal char or peat in the presence of ammonia or a nitrogenous organic base capable of forming a complex with the metal, which may be added to the solution or impregnated into the adsorbent. The metals extracted may be Cu, Zn, Ni, Cd, Ag, Co, Fe, U, Cr or Mn, from their sulphate or nitrate solns. The base may be methylamine, dimethylamine, trimethylamine, triethanolamine, pyridine or quinoline. The solution may also contain an ammonium salt. Precious metals, e.g. Au, Pt, Pd or Rh, can be extracted from solution, e.g. gold chloride or cyanide) by use of the adsorbent which has been loaded with metal, e.g. Zn or Cu by the above process and partially oxidized, the Zn or Cu being displaced. The metals may be recovered from the adsorbent by oxidation of the adsorbent with reduction of the resulting metal oxide if necessary, by melting, e.g. with CaF 2 flux, by extraction with acid, or by volatilization, e.g. as Ni carbonyl.</p> |
