Enargite is a representative arsenic-bearing copper resource, and pyrite is often found co-existed with it. Understanding the effect of pyrite on enargite (bio)leaching is of vital importance for the recovery of copper from enargite. The galvanic interaction between enargite and pyrite in bioleaching and electrochemical systems was investigated. Bioleaching experiment showed that the addition of pyrite significantly promoted the enargite leaching rate due to the galvanic effect. However, the pyrite promotion effect on the enargite leaching rate decreased due to the oxidation of pyrite and the surface area of pyrite reduced in the bioleaching process. The dissolution rate of enargite without pyrite was controlled by diffusion through a product film, suggesting a passivation layer formed around the enargite surface. The presence of pyrite changed the rate-limiting factor of enargite dissolution to the surface chemical control, indicating that the addition of pyrite eliminated the passive effect. Electrochemical studies showed the mixed potentials (E_M) and dissolution current densities (I_diss) of enargite electrodes increased when the enargite was in contact with a pyrite electrode, and the E_mix and I_dis further increased with increasing the surface area of the pyrite electrode. The effect of the pyrite electrode surface area on the dissolution of enargite electrodes was quantified by the kinetics of the half-cell reactions occurring in the pyrite-enargite galvanic couple under mixed potentials with oxygen and ferric ions as oxidants. Electrochemical impedance spectroscopy studies demonstrated a significant decrease in the charge transfer resistance and passivation film resistance of the enargite electrode in contact with pyrite, indicating that the cathodic reduction controlled the dissolution of enargite electrode and galvanically coupled pyrite continued to act as a cathode to facilitate the oxidation of enargite by oxygen and ferric ions even after enargite was passivated.

镁辉石是一种代表性的含砷铜资源，黄铁矿经常与之共存。了解黄铁矿对菱镁矿（生物）浸出的影响，对于从菱镁矿中回收铜至关重要。研究了生物浸出和电化学体系中的辉铝矿和黄铁矿之间的电相互作用。生物浸出实验表明，黄铁矿的加入由于其电化作用而显着提高了菱镁矿的浸出率。然而，由于黄铁矿的氧化和生物浸出过程中黄铁矿的表面积减少，黄铁矿对凝结岩浸出速率的促进作用降低。通过在产品膜中的扩散来控制没有黄铁矿的硬铝辉石的溶解速率，这表明在硬铝石表面周围形成了钝化层。黄铁矿的存在改变了褐铁矿溶解到表面化学控制的速率限制因素，表明添加黄铁矿消除了被动效应。电化学研究表明混合电势（E当配合物与黄铁矿电极接触时，E_混合物和I _dis增大，使配合物电极的_M）和溶解电流密度（I _diss）增加。随黄铁矿电极表面积的增加而进一步增加。通过在氧和铁离子作为氧化剂的混合电势下，在黄铁矿-磁铁矿电偶中发生的半电池反应的动力学，定量了黄铁矿电极表面积对钙铁矿电极溶解的影响。电化学阻抗谱研究表明，与黄铁矿接触的钠辉石电极的电荷转移电阻和钝化膜电阻显着降低，这表明阴极还原控制了钠辉石电极的溶解，并且电耦合黄铁矿继续充当阴极，从而促进了黄铁矿的形成。即使钝化了辉石，也会被氧和三价铁离子氧化成辉石。