Studies on recovery of Ni, Co & Cu from polymetallic sea nodules by direct reduction smelting

A world-wide research is progressing on sea nodules as an alternative future source of various metals like nickel, cobalt, copper etc. which are fast depleting from the earth surface. Sea nodule collected from Indian Ocean containing 1.2% Ni, 1.1% Cu, 0.08% Co, and 24.3% Mn was treated to recover metal as alloy by direct reduction smelting. Various parameters like smelting temperature, reductant concentration, holding time etc. have been optimized to obtain an alloy of suitable composition. At a smelting temperature of 1400 oC, recovery of 92-95% Ni, 75 - 80% Co and 90-92% Cu is obtained in the form of alloy which can be further treated to recover these metals in pure form.