| 摘要 |
<p>Milled mineral particles are digested with MgSO4 soln. recycled from a later stage, and the pulp slurry washed with strong H2SO4, which in the presence of the MgSO4 facilitates the pptn. of Fe and Al-vaues (minimising the risk of alum formation at later stages). Gangue material is removed, and the liquor neutralised with highly active MgO to ppte. Ni(OH)2, which is extracted and purified by complexing with NH3 and (NH4)2 SO4. The extracted Ni is worked up conventionally to yield Ni, NiO or Ni plate. The MgSO4 soln. liquor is partly recycled to the digestion stage and partly calcined to form MgO and regenerate H2SO4. Cu and Co are spd. resp. by cementation and selective reduction. The process is economical and minimal losses of H2SO4 are involved.</p> |
