| 摘要 |
Metals are extracted from aqueous solutions by means of an alkali metal, e.g. Na, K, naphthenate dissolved in a non-polar organic solvent, e.g. kerosene. The extraction may be carried out at 40-80 DEG C. using an excess of up to 50% naphthenate, and the ratio of organic/aqueous phase is varied to extract the metals separately. The metals are re-extracted by treating the organic solution with HCl or H2SO4, in a single stage, or fractionally, and the resulting naphthenic acid is used to form fresh alkali metal naphthenate and recycled. The initial aqueous solution may be obtained by hydrometallurgical treatment of ores or concentrates, e.g. pyrites ashes. Fe3+ may be preliminarily extracted with a solution of an alkali metal C7-C9 fatty acid salt in kerosene. The remaining solution contains Cu, Zn, Na, and some Fe; Cu and Fe3+ are first extracted (then reextracted separately into aqueous phase); Zn and some Cu and Fe are then extracted (then reextracted separately, and the Cu and Fe solution recycled); the alkali metal salt, e.g. Na2SO7, which has accumulated in the primary aqueous solution, can then be recovered, e.g. by atomization.ALSO:A metal naphthenate, e.g. of Cu, Fe or Zn, is obtained by extraction of the metal from an aqueous solution using an alkali metal naphthenate dissolved in a non-polar organic solvent, e.g. kerosene. The extraction may be carried out at 40-80 DEG C. using an excess of up to 50% naphthenate, and the ratio of organic/aqueous phase is varied to extract the metals separately. |
