Study on the Galvanic Interaction of Gold and Main Associated Minerals Based on Density Functional Theory

Abstract

The galvanic interaction of gold and associated sulfide minerals in thiocyanate systems has a significant impact on gold leaching. The density functional theory was used to further reveal the galvanic interaction between gold and associated minerals. The electron transfer between gold and its associated minerals at different galvanic interaction distances was simulated. The results show that with the increase of the contact distance between pyrite and gold, the charge of pyrite increases, indicating that it is losing electrons gradually; the charge of arsenopyrite and chalcocite decreases with the rise of the contact distance between gold and pyrite, suggesting that they are gaining electrons. In addition, gold has the greatest influence on the gain and loss of electrons in pyrite and arsenopyrite and has the least influence on chalcocite. Through the calculation of the density of states, it is found that different distances of galvanic interaction have a great influence on the density of states of surface atoms under the action of pyrite and arsenopyrite with gold but have little effect on the density of states of surface atoms under the action of chalcocite with gold.