Selective Recovery of Nickel, Cobalt, Manganese from Sea Nodules With Sulfurous Acid.
U S Pat 4 138 465 1979 Feb; :
Nickel, cobalt, and manganese are recovered from marine nodules by leaching with h2so3. Nickel and CO are selectively extracted from copper by adjustment of process variables such as leach time, volume, and acid concentration. Thus, the nodules are ground to < approximately 100 mesh and leached with a solution of dilute h2so3 at 25 deg c and 1 atm. The ratio of total moles of so2 in the leach solution to the weight of ground nodules is approximately 0.94-1.25 For complete extraction of ni, CO, and mn without appreciable extraction of cu.
U.S. Pat. 4,138,465; Feb. 6, 1979; Chem. Abstr. 90:90,541N