Dissolution and passivation mechanisms of chalcopyrite during bioleaching: DFT calculation, XPS and electrochemistry analysis
Dissolution and passivation mechanisms of chalcopyrite during bioleaching: DFT calculation, XPS and electrochemistry analysis
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生物浸出过程中黄铜矿的溶解和钝化机制：DFT计算、XPS和电化学分析
DOI：
10.1016/j.mineng.2016.09.008
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发表时间：
2016-11
影响因子：
4.8
通讯作者：
Guanzhou Qiu
中科院分区：
文献类型：
--
作者：
Jun Wang;Xiaowen Gan;Hongbo Zhao;Minghao Hu;Kaiyun Li;Wenqing Qin;Guanzhou Qiu
本工作通过密度泛函理论（DFT）计算、X射线光电子能谱（XPS）和电化学分析研究了硫和铁氧化微生物存在下黄铜矿的溶解过程和钝化机制。 DFT计算和XPS分析均表明黄铜矿的分子式应为Cu + Fe3+ (S2−)2。由于表面重构，黄铜矿表面很容易形成二硫化物（S22−）和多硫化物（Sn2−）。生物浸出中黄铜矿的溶解过程主要依赖于氧化还原电位。当氧化还原电位相对于 Ag/AgCl 低于约 350 mV 时，黄铜矿主要直接氧化为多硫化物，并导致溶解速率较低。当氧化还原电位相对于 Ag/AgCl 约为 350–480 mV 时，黄铜矿主要转化为 Cu2S 中间物质而不是多硫化物，从而导致高溶解率。当氧化还原电位相对于 Ag/AgCl 高于约 480 mV 时，黄铜矿主要直接氧化成多硫化物，从而导致黄铜矿钝化。最后，提供了硫和铁氧化微生物存在下黄铜矿的溶解和钝化机制的模型。
In this work, density functional theory (DFT) calculation, X-ray photoelectron spectroscopy (XPS) and electrochemistry analysis were carried out to investigate the dissolution process and passivation mechanisms of chalcopyrite in the presence of sulfur and iron oxidizing microorganisms. Both DFT calculation and XPS analysis indicated that the formula of chalcopyrite should be Cu + Fe3+ (S2−)2. Disulfide (S22−) and polysulfide (Sn2−) can be easily formed on the surface of chalcopyrite due to the surface reconstruction. The dissolution process of chalcopyrite in bioleaching was mainly dependent on redox potential. Chalcopyrite was predominantly directly oxidized to polysulfide when redox potential was lower than about 350 mV vs. Ag/AgCl and resulted in low dissolution rate. When redox potential was in the range of about 350–480 mV vs. Ag/AgCl, chalcopyrite was mainly transformed to intermediate species of Cu2S rather than polysulfide, thus resulting in high dissolution rate. When redox potential was higher than about 480 mV vs. Ag/AgCl, chalcopyrite was principally directly oxidized to polysulfide which caused the passivation of chalcopyrite. Finally, a model of dissolution and passivation mechanisms of chalcopyrite in the presence of sulfur and iron oxidizing microorganisms was provided.
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影响因子：
4.8
作者：
Yi Yang;Weihua Liu;Miao Chen
通讯作者：
Yi Yang;Weihua Liu;Miao Chen
氧化还原电位对中度嗜热细菌生物浸出黄铜矿的影响：强调溶液成分
影响因子：
4.7
作者：
Hongbo Zhao;Jun Wang;Congren Yang;Minghao Hu;Xiaowen Gan;Lang Tao;Wenqing Qin;Guanzhou Qiu
通讯作者：
Guanzhou Qiu
影响因子：
6.7
作者：
R. Edelbro;Å. Sandström;J. Paul
通讯作者：
R. Edelbro;Å. Sandström;J. Paul
影响因子：
3.8
作者：
K. Third;R. Cord-Ruwisch;H. Watling
通讯作者：
K. Third;R. Cord-Ruwisch;H. Watling
影响因子：
1.7
作者：
E. Baerends
通讯作者：
E. Baerends