Abstract: The metal content of nickel-cobalt mixed sulfide slurries is recovered by atmospheric oxidation leaching, thereafter removing dissolved copper by metathesis with further mixed sulfide feed, treating the filtrate after liquid-solids separation with ammonia to selectively precipitate cobalt, separating the cobalt precipitate and working up the resulting filtrate to recover nickel.

Abstract: A process for recovering metal values from sulfide ores or concentrates by a fluid bed roast-reduction smelting-converting process which delivers to the reduction smelting furnace either a blend of dead roasted concentrate and green concentrate or a partially roasted concentrate, either feed mixed with a carbonaceous reductant and silica flux, and either feed containing only sufficient sulfur to produce a matte, in which the iron is present as metallic iron, and which has a sulfur deficiency of about 0% to about 25% with respect to base metals, and which is later converted to a low iron matte by blowing and slagging the iron with silica flux.