| 摘要 |
1437192 Precipitation of metal carbonates INTERNATIONAL NICKEL CO OF CANADA Ltd 10 Sept 1973 [11 Sept 1972] 42445/73 Heading C1A The preparation of a precipitate of the carbonate or basic carbonate of Ni, Co, Cu or Zn is carried out by mixing a stream of an aqueous solution of a water-soluble salt of Ni, Co, Cu or Zn substantially continuously in an agitated reaction zone at 40-60‹ C. and at pH 7À4- 7À8 with a stream of an aqueous solution of an alkali metal carbonate plus optionally alkali metal hydroxide or bicarbonate and the resulting precipitate is recovered, the amount of alkali metal carbonate and hydroxide or bicarbonate, expressed as alkali metal, being that required to use up any free acid in the salt solution and additionally 100-127% of the theoretical stoichiometrie amount required to precipitate the pure normal carbonate. It is preferred to use the sulphate salts of Ni, Co, Cu or Zn and to carry out the precipitation with aeration at 45-55‹ C., the product being easily filterable and highly reactive. |
