| 摘要 |
<p>In the hydrometallurgical treatment of anode slurry from copper electrolysis and similar raw materials, which in addition to silver may also contain a range of other metals, the starting product, from which acid-soluble copper and nickel and also lead have been removed, is formed into a slurry with hydrochloric acid and passed to a sodium hypochlorite solution. This environmentally friendly direct chlorination of the anode slurry dissolves the Au, the platinum metals, Se, Te and similar metals and separates them off by filtration, while the Ag is converted into AgCl and remains in the residual slurry. The silver is then removed from this by extraction using ammonia, and the Ag(NH3)2Cl solution obtained is mixed with Cu<I> compounds, the Ag<+> being quantitatively precipitated to form metallic Ag and being melted to form metallic Ag after filtration, washing and drying, while the filtrate is mixed with calcium hydroxide, the ammonia is recovered by distillation and the filter cake obtained after the filtration is returned to the metallurgical process.</p> |
