(1. 北京科技大学 土木与资源工程学院，北京 100083;
2. 中国科学院 过程工程研究所 生化工程重点实验室，北京 100190)
摘 要: 为利用多金属结核与低品位硫化镍矿，提出嗜酸氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans，At. f 菌)共浸出镍、钴、铜、锰工艺，考察有无Fe(Ⅲ)和At. f菌体系中S/Mn矿石质量比、矿浆浓度、搅拌速度、温度、接菌量和pH值对主金属元素浸出的影响，通过循环伏安、电化学极化、计时电流、XRD和SEM等分析手段揭示多金属共浸出过程中At. f菌的增速作用机理。结果表明：At. f菌可提高主金属元素浸出速度和回收率；At. f菌存在时，多金属结核阴极-低品位镍矿阳极电极间电位差增大，Fe3+/Fe2+和S0/S2-氧化还原加快，从而加速腐蚀反应。At. f菌促进多金属结核溶解过程电子转移和物质交换，引起低品位硫化镍矿氧化还原电位负移并释放吸附矿石表面S0电子。有菌浸取时的镍、锰、铜和钴浸出率分别达95.34%、97.34%、92.24%和97.75%，比无菌浸取时的分别提高8.78%、4.78%、10.34%和5.46%。
关键字: 生物共浸出；电位差；电化学极化；电子转移；氧化还原
（1. School of Civil and Resource Engineering, University of Science and Technology, Beijing 100083, China;
2. Key State Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China）
Abstract:For the extraction of Ni, Cu, Co, and Mn from polymetallic nodule and low-grade nickel sulfide ore, a simultaneous bioleaching was investigated by using Acidithiobacillus ferrooxidans(At. f). The extraction regularity was measured by effect of mass ratio of S/Mn, pulp density, agitation speed, temperature, inoculation amount of bacteria and pH on the leaching of major metal elements. The feature and mechanism of the acceleration of At. f was determined by cyclic voltammetry, electrochemical polarization-curve, chronoamperometry, XRD and SEM analysis. The results show that the leaching rate and recovery of major metal elements increase with admixing At. f. Acidithiobacillus ferrooxidans prospers the corrosion, by accelerating the mutual transformation of Fe3+/Fe2+ and S0/S2- electron couples and by increasing the potential difference between the anode of low-grade nickel sulfide ore and the cathode of polymetallic nodule. Acidithiobacillus ferrooxidans can also improve the electron transfer and substance exchange in the dissolution of polymetallic nodules, cause a negative movement of the corrosion potential of nickel ore, and increase in the electron release of the adherent S0. With the presence of At. f, the extraction ratios of Ni, Mn, Cu and Co during bioleaching are 95.34%, 97.34%, 92.24% and 97.75%, respectively, and more than those during inorganic leaching by 8.78%, 4.78%, 10.34% and 5.46%.
Key words: simultaneous bioleaching; potential difference; electrochemical polarization-curve; electron transfer; oxidation-reduction
