Fuel oil reduction of polymetallic manganese sea nodules of Indian Ocean for extraction of nickel, copper and cobalt

The sea nodules from National Institute of Oceanography, Goa were subjected to reduction roast with fuel oil alongwith sodium chloride and were then leached with ammonia and ammonium carbonate solution. The different process parameters studied in reduction roast were effects of temperature, amount of fuel oil and quantity of additive. The kinetics of leaching and the effect of concentration of leachant were studied in detail. The recoveries of nickel, copper and cobalt were 93.0%, 99.0% and 78.0% respectively on reduction of nodules at 750°C for 1 hour and subsequent ammonia leaching of the calcine for 4 hours.