(1. 中国科学院过程工程研究所 湿法冶金清洁生产技术国家工程实验室 生化工程国家重点实验室,
北京 100190
2. 国家安全监管总局信息研究院,北京 100029)
摘 要: 分别采用嗜酸氧化亚铁硫杆菌(At.f)、嗜酸氧化硫硫杆菌(At.t)以及中度嗜热西伯利亚硫杆菌(S.s)对雌黄进行浸出。结果表明:嗜酸氧化硫硫杆菌浸出雌黄的效果较好,浸出过程是细菌直接与矿物作用;中温菌浸出雌黄则主要通过将Fe2+氧化成Fe3+,再由Fe3+氧化溶解矿物,浸出后期在矿物表面生成覆盖层;嗜酸氧化亚铁硫杆菌很难在雌黄矿浆中生长;添加适量表面活性剂Tween-80能有效改善矿物表面润湿性,促进Fe3+对砷的浸出,但对细菌生长会造成影响,抑制细菌直接浸出。
关键字: 雌黄;生物浸出;常温菌;中温菌;表面活性剂
(1.National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;
2. National Institute of Occupational Safety, Beijing 100029, China)
Abstract:The orpiment was bioleached with Acidithiobacillus ferrooxidans(At.f), Acidithiobacillus thiooxidans(At.t) and Sulfobacillus sibiricu(S.s) in batch experiments. The results show that the orpiment can be leached with T.t and S.s, but At.f can not grow in the slurry. At.t and S.s show different mechanisms during the bioleaching of orpiment. In the At.t bioleaching, the dissolution of orpiment is mainly caused by the bacteria attached onto the mineral surface. In the S.s bioleaching, the orpiment is dissolved by Fe3+ that is generated by the bacterial oxidation of Fe2+, and the mineral surface is covered by precipitation during the later stage of the leaching process. The addition of surfactant Tween−80 can enhance the Fe3+ leaching by improving the hydrophilicity of minerals, but inhibit the direct bacterial oxidation of orpiment.
Key words: orpiment; bioleaching; mesophilic bacteria; moderately thermophilic bacteria; surfactant