混合高温菌浸出黄铜矿及浸出过程中微生物群落的演替

Bioleaching of chalcopyrite concentrate using mixed thermophilic culture and succession of microbial community during leaching process

研究3株极端嗜热古菌(金属硫叶菌,Sulfolobus metallicus JCM9184;瑟杜生金属球菌,Metallosphaera sedula JCM9185和万座酸菌,Acidianus manzaensis YN25)在不同起始pH值和不同温度条件下对黄铜矿的混合浸出,并对浸矿过程中混合菌群落的动态演替进行分析。结果表明:在起始pH1.5时的铜浸出率明显高于在起始pH2.5时的铜浸出率,而65℃条件下的铜浸出率高于75℃时的铜浸出率。利用限制性长度多态性(RFLP)分析65℃、起始pH1.5条件下的微生物群落演替,结果显示:在黄铜矿的浸出前期Sulfolobus metallicus是占据优势的菌种,而到后期Acidianus manzaensis的比例则会上升,并最后取代Sulfolobus metallicus成为优势种。

A mixed thennophilic culture consisting of Sulfolobus metallicus JCM 9184, Metallosphaera sedula JCM 9185 and Acidianus manzaensis YN25 was used to study the combined effect of pH value and temperature in bioleaching of a chalcopyrite Concentrate. The results show that the copper extraction at initial pH 1.5 is higher than that at intial pH 2.5. The copper extraction at 75℃ is lower than that at 65℃, but the lower copper extraction at 75℃ is not due to the inhibition of the high temperature. The succession of the microbial community during the leaching process was analysed by restriction fragment length polymorphism （RFLP）. The analysis shows that Sulfolobus metallicus is dominant in the microbial community at the early stage of leaching, whereas Acidianus manzaensis thrives at the latter stage. This phenomenon might be caused by the change of ferrous ion concentration during leaching process.