A study of the recovery of copper, cobalt, nickel and zinc from copper
converter slag by roasting with ferric sulphate is reported. Roasting
of converter slag with ferric sulphate, followed by leaching with wat
er, was carried out in order to bring the metal values into solution.
For 500 degrees C roasting temperature, 120 min roasting time and Fe-2
(SO4)(3) . xH(2)O/slag = 1 ratio, recoveries of copper, cobalt, nickel
and zinc were about 93%; 38%; 13% and 59%, respectively. Higher extra
ction yields could be achieved with a higher ratio of Fe-2(SO4)(3) . x
H2O/slag for copper and zinc, whereas cobalt and nickel could not be e
xtracted in acceptable yields. Using H2SO4 in the leaching process mar
kedly improves the metal recoveries.