摘要
To estimate the relationships among bioleaching performance, additional elemental sulfur （S0）, microbial population dynamics and its energy metabolism, bioleaching of chalcopyrite by three typical sulfur- and/or iron-oxidizing bacteria, Acidithiobacillus ferrooxidans, Leptospirillum ferriphilum and Acidithiobacillus thiooxidans with different levels of sulfur were studied in batch shake flask cultures incubated at 30 °C. Copper dissolution capability （71%） was increased with the addition of 3.193 g/L S0, compared to that （67%） without S0. However, lower copper extraction was obtained in bioleaching with excessive sulfur. Microbial population dynamics during chalcopyrite bioleaching process was monitored by using PCR-restriction fragment length polymorphism （PCR-RFLP）. Additional S0 accelerated the growth of sulfur-oxidizing bacteria, inhibited the iron-oxidizing metabolism and led to the decrease of iron-oxidizing microorganisms, finally affected iron concentration, redox potential and bioleaching performance. It is suggested that mixed iron and sulfur-oxidizing microorganisms with further optimized additional S0 concentration could improve copper recovery from chalcopyrite.
研究3种典型铁/硫代谢菌—Acidithiobacillus ferrooxidans,Leptospirillum ferriphilum及Acidithiobacillus thiooxidans混合浸出黄铜矿过程中铁/硫氧化活性、群落结构(PCR-RFLP)的变化,以及不同浓度的元素硫对其影响。结果发现,加入3.193g/L元素硫能促进细菌的表观硫氧化活性,改变浸矿体系的群落结构,并进一步影响钝化层的形成、金属离子的溶出,其浸出率(71%)较未添加硫的(67%)有一定程度的提高。而过量的元素硫会抑制铜的浸出(浸出率44%)。
基金
Project (20803094) supported by the National Natural Science Foundation of China
Project (20100471233) supported by the Postdoctoral Foundation of China and the Postdoctoral Foundation of Central South University
