Bulk flotation of auriferous pyrite and arsenopyrite by using tertiary dodecyl mercaptan as collector in weak alkaline pulp

摘要

Laboratory and industrial scale experiments were conducted to investigate the effect of tertiary dodecyl mercaptan (TDM) as collector on the flotation of auriferous pyrite and arsenopyrite. Laboratory tests results show that TDM can improve the recovery of gold and greatly reduce the consumption of activators. It was observed that optimum recovery of gold was obtained by mixture use of TDM and sodium butyl xanthate, together with only a few copper sulphate as activator in weak alkaline pulp adjusted by sodium hydroxide. The two-month industrial data at Liumei plant in Guangxi Province show that a recovery of 90.79% into a concentrate assaying 81.10 g/t Au from a feed assaying 2.94 g/t Au have been achieved at pH 8-8.5 using TDM as collector. The Au recovery is enhanced by 6.72% and the cost of reagents is decreased by 50% due to the absence of sulfuric acid and the reduce of copper sulphate and collector. The mechanism of TDM interacted with pyrite and arsenopyrite has been studied by infrared spectrum and quantum chemistry method.