(1. 北京有色金属研究总院, 北京 100088;
2. 中南大学 资源加工与生物工程学院, 长沙 410083;
3. 福建紫金矿业股份有限公司, 上杭 364200)
摘 要: 研究了黄铜矿与黄铁矿混合矿细菌浸出过程的原电池效应, 提出了原电池效应模型。 研究结果表明: 当黄铜矿细菌浸出过程中加入黄铁矿及C时, 浸出率大大提高, 黄铜矿浸出30d, Cu浸出率可达40%; 单一黄铁矿细菌浸出时, 黄铁矿会被大量氧化分解, 而当与黄铜矿混合浸出时,黄铜矿氧化加快, 黄铁矿氧化速率降低; 加入C及黄铁矿与黄铜矿混合时, 由于接触电位的影响, 黄铜矿氧化反应电流增大、 反应起始电位负移, 反应加剧, 而黄铁矿的氧化反应受到抑制; 混合矿浸出过程中, 黄铜矿表面Cu含量较单一矿浸出时低得多, 说明混合效应对浸出具有强化作用; 黄铜矿中Cu浸出愈多, 表面生成的元素硫愈多, 黄铁矿细菌浸出时, 表面不会有元素硫产生。
关键字: 细菌浸出; 原电池效应; 粉末微电极; 电化学机理
(1. General Research Institute of Nonferrous Metal, Beijing 100088, China;
2. School of Resources Processing and Bioengineering, Changsha 410083, China;
3. Fujian Zijin Minning, Shanghang 364200, China)
Abstract:The galvanic effect of pyrite and chalcopyrite mixed sulfide at bio-leaching was investigated. It is indicated that the chalcopyrite leaching rate increases after adding pyrite as well as carbon, after leached 30d, the leaching date is up to 36%. The results show that in the presence of bacteria the pyrite will be oxidized greatly, but when mixed with chalcopyrite, few pyrite is oxidized, however the oxidation of chalcopyrite is increased. The CV curve demonstrates that when pyrite and carbon are added, the current of oxidation peak of chalcopyrite increases, the potential decreases and the reaction rate increases. The surface EDS analysis reveals that the galvanic effect of mixed sulfide strengthens the oxidation of mineral. During bio-leaching, to the chalcopyrite, the more Cu is leached, the more element sulfur can form on the mineral surface, but to the pyrite, no element sulfur is on the surface.
Key words: bioleaching; galvanic effect; powder microelectrode


