摘要 |
<p>1362683 Copper and nickel recovery KENNECOTT COPPER CORP 16 July 1971 [16 July 1970] 33601/71 Heading C1A Copper and nickel values are obtained from iron containing deep sea manganese nodules or an equivalent complex ore by reducing the ore with a gaseous reducing agent at 249‹C. to 899‹ C., leaching the reduced ore (substantially free of metallic iron) with an aqueous solution of ammonia and an ammonium salt and separating off the leach solution containing the copper and nickel values (Co and Mo values may also be contained). The reducing gas may be synthesis gas, a CO/CO2 mixture, a CO/H2 mixture, water gas, and combustion gas from the controlled burning of fuel oil and natural gas. A weaker reducing gas may be used at the higher temperatures, e.g. by adding a diluent such as CO2 or water vapour. The reduction may be carried out in a fluidized bed, a static bed of deep sea nodules where the reducing gas percolates upward or downward, or on a travelling gate wherein the gas passes over the nodules. Prior to leaching the reduced nodules may be cooled in an inert atmosphere and subsequent to leaching if ammonium carbonate is used the metal values may be precipitated as basic carbonates by stripping off ammonia and CO2. The examples also describe the use of aeration or an inert atmosphere during leaching, and of grinding the ore prior to reduction. Other ammonium salts include ammonium chloride and ammonium sulphate.</p> |