硫脲浸取硫化金精矿及其焙砂的比较研究

COMPARATIVE STUDY ON THE THIOUREA-LEACHING OF GOLD AND SILVER FROM A SULPHIDE CONCENTRATE AND ITS CALCINE

用硫脲法浸取含铜硫化金精矿及其焙砂时,直接浸取硫化矿,硫脲消耗高,过程操作困难、金的浸出率仅为60—70%,且不稳定.采取在浆挂铁板和加活性炭,也仅能达87—91%;而经硫酸化焙烧的焙砂,用烯酸预浸回收铜,再用硫脲浸取金、银,硫脲消耗低,过程易于操作,金、铜和银浸出率分别可达98%、90%和91%且稳定,综合经济效益显著.

This work investigates different behaviors of gold and silver in the leaching from a sulphide concentrate containing copper and its calcine with acidic thiourea solutions. It was found that when the sulphide concentrate was directly leached,the consumption of thiourea was high,and the operation conditions were difficult to control,resulting in a recovery of gold only about 60-70%.With the use of iron plate or activated carbon in leaching,the gold recovery could reach 87-91%.After sulphating roasting,the calcine was subjected to removal of copper with dilute sulphuric acid,followed by leaching with acidic thiourea solutions.The recovery of gold,silver and copper were 98,91 and 90%,respectively.The leaching data could be reproduced very well.The operation conditions were easy to control,and the consumption of thiourea was low.