Foam Treatment of the Leached Solution of Manganese Nodule

Abstract

Manganese nodules, after pulverizing, were oxidized by heating and were leached with dilute acid. The leaching was carried at 95°C for 5 hr using 120 ml of 0.1 N hydrochloric acid per 1 gram of the sample oxidized at 500°C for 3 hr. By these treatments, 99.2% of copper, 68.2% of nickel and 36.5% of cobalt were extracted. By the foam treatment of the leached solution with the aid of N-decanoyldiethylenetriamine, copper and nickel were recovered selectively without interference of the co-existent heavy metal ions. Studies on the conditions of the foam treatment of the leached solutions of various comositions revealed that, by applying the suitable conditions, copper, nickel and cobalt could be recovered selectively as foam. It was also found that the co-existence of aluminum ions enabled us to recover copper selectively without accompanying iron (III) ions.