Thermodynamics and density functional theory study of potassium dichromate interaction with galena

Abstract

The adsorption heat and reaction rate constant of potassium dichromate on the surface of galena were studied. The results indicate that potassium dichromate tends to adsorption on the galena surface. The reaction order is only 0.08385, suggesting that the concentration of potassium dichromate has little influence on its adsorption on the galena surface. In addition, the simulation of CrO₄ ²⁻ adsorption on the PbS (100) surface in the absence and presence of O₂ was carried out by density functional theory (DFT). The calculated results show that CrO₄ ²⁻ species adsorb energetically at the Pb-S bond site, and the presence of O₂ can enhance this adsorption.

Keywords

flotation / potassium dichromate / galena / adsorption / thermodynamics / density functional theory

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