论文部分内容阅读
运用循环伏安、稳态极化扫描和交流阻抗等电化学测试方法,研究黄铁矿在氧化亚铁硫杆菌浸矿体系和无菌酸性体系下的电化学氧化机理。结果表明,在无菌和A.ferrooxidans菌存在的条件下,黄铁矿的氧化反应分为两步:第一步是黄铁矿氧化生成元素S;第二步是元素S被氧化生成SO42-。加入A.ferrooxidans后黄铁矿的氧化机理没有发生改变,但是氧化速度加快。随着黄铁矿与A.ferrooxidans作用时间的延长,极化电流密度增加,黄铁矿表面钝化膜溶解的点蚀电位降低。在细菌存在的条件下,电极的阻抗值下降,表明微生物的存在加速了黄铁矿电极的腐蚀作用,有利于黄铁矿的氧化溶解。
Cyclic voltammetry, steady-state polarization scanning and electrochemical impedance spectroscopy were used to study the electrochemical oxidation mechanism of pyrite under the conditions of the soaking system of Thiobacillus ferrooxidans and aseptic acidic system. The results showed that in the presence of bacteria and A.ferrooxidans, the oxidation reaction of pyrite is divided into two steps: the first step is the oxidation of pyrite to element S; the second step is the oxidation of element S to SO42- . The oxidation mechanism of pyrite did not change after adding A. ferrooxidans, but the oxidation rate accelerated. With the extension of time of pyrite and A. ferrooxidans, the polarization current density increases, and the pitting potential of the passive film dissolves on the pyrite surface decreases. In the presence of bacteria, the impedance of the electrode decreased, indicating that the presence of microorganisms accelerated the pyrite electrode corrosion, is conducive to the oxidation and dissolution of pyrite.