AN IMPROVED PROCESS FOR NICKEL AND COBALT EXTRACTION FROM LATERTIC AND LIMONITIC NICKELIFEROUS ORES.

摘要

In a process for recovery of nickel and/or cobalt in the form of nickel and/or cobalt basic carbonate/s from lateritic or limonitic nickeliferous oxides or silicate ores which comprises the steps of selective reduction of the one, characterized in the step of treating the said selectively reduced ore to above atmospheric pressure with ammonia-ammonium carbonate liquor which comprises adjusting the ammonia concentration of the said liquor within 65 to 150 gpl and carbon dioxide within 35 to 75 gpl and passing simultaneously an oxygen bearing oxidising gas therethrough for a time sufficient to substantially dissolve the nickel and cobalt and sulphur whenIn a process for recovery of nickel and/or cobalt in the form of nickel and/or cobalt basic carbonate/s from lateritic or limonitic nickeliferous oxides or silicate ores which comprises the steps of selective reduction of the one, characterized in the step of treating the said selectively reduced ore to above atmospheric pressure with ammonia-ammonium carbonate liquor which comprises adjusting the ammonia concentration of the said liquor within 65 to 150 gpl and carbon dioxide within 35 to 75 gpl and passing simultaneously an oxygen bearing oxidising gas therethrough for a time sufficient to substantially dissolve the nickel and cobalt and sulphur whenpresent in the reducing agent of said reduction step to form soluble nickel and cobalt ammine complexes and soluble sulphur compound in the ammonia-ammonium carbonate liquor. ?? ?? ?? ?? 5 135348