Abstract:The cobalt-nickel matte, a reduction product from nickel converter slag by vulcanization smelting, was atmospherically pressure leached at the sulfuric acid system. The effects of sulfuric acid concentration, ratio of liquid to solid (L/S), leaching time and temperature on leaching rate of valuable metals were investigated. The results show that L/S and sulfuric acid concentration have great influence on the leaching rate of cobalt, nickel and ferrum. The ferrum leaching rate reaches 69%, nickel and cobalt leaching rate could be controlled below 1% and 5% respectively under the conditions including sulfuric acid concentration of 1.6 mol/L, L/S of 5, leaching time of 2.5 h, and leaching temperature of 85 ℃, A good selectivity leaching effect was obtained.