钴渣氨浸工艺的研究

Studies on Process for Ammonia Leaching of Cobalt Dregs

研究了钴渣的氨浸工艺。在钴渣氨浸过程中 ,用亚硫酸钠将钴渣中三价钴还原成二价钴 ,可较大程度地提高钴的浸出率。实验中 ,在氨水浓度为 14% ,硫酸铵浓度为 16 0g/L ,液固比为 8∶1条件下 ,浸出液与钴渣在70℃下反应 30min ,然后加入二倍钴量 (摩尔比 )的还原剂亚硫酸钠于 5 0℃下浸出 5h ,钴的浸出率达到了 97 46 % ,镍的浸出率为 95 0 0 %

The process for ammonia leaching of cobalt dregs was studied. In the course of ammonia leaching of cobalt dregs, the yield of cobalt can increase greatly when cobaltic(Ⅲ) is reduced to coboltous(Ⅱ) by the reductant such as sodium sulfite. In the experiment,when the concentration of ammonia water is 14%,the concentration of ammonium sulfate is 160 g/L and the ratio of liquid solid is 8∶1, the cobalt dregs were reacted with leaching solution for 30 min at 70℃. Then double ammount of the reductant sodium sulfite with respect to the amount of cobalt (mol ratio) was added and the leaching reaction was continued for another 5 h at 50℃. The yield of cobalt and nickel are 97.46% and 95 00%, respectively.