Density functional theory and experimental studies of Cu2+ activation on a cyanide-leached sphalerite surface

Density functional theory calculations, flotation behavior, X-ray photoelectron spectroscopy, and infrared spectra were combined to reveal the Cu2+ activation mechanism on a cyanide (CN−)-leached sphalerite surface. Low CN− adsorption enhanced the activation capability of Cu2+ on the sphalerite surface, whereas the hydrophilicity of the sphalerite increased with increasing CN− coverage, which hindered Cu2+ adsorption. As the amount of chemically adsorbed Cu2+ on the sphalerite surface increased, Cu2+ began to desorb CN−, leading to the same result, which is consistent with the low CN− coverage.