Interface adsorption of 5-amino-1,3,4-thiadiazole-2-thiol on chalcopyrite surface as flotation depressant in Cu/Mo separation

Abstract

Flotation is an interfacial chemical reaction in essence. The selective adsorption of flotation reagents on mineral surfaces leads to the transition of hydrophilicity/hydrophobicity of mineral particles, and then to regulate the floatability differences between various minerals. 5-amino-1,3,4-thiadiazole-2-thiol (ATT) is a heterocyclic ring compound, which can chelate copper ions easily and usually used as a copper corrosion inhibitor. Based on those good chelating properties with copper ions, this paper attempted to apply ATT as a chalcopyrite depressant in the flotation separation of Cu/Mo ores. The adsorption mechanism of ATT on chalcopyrite surface was explored by means of UV–vis, FTIR, contact angle and XPS analysis, and it revealed the possibility of ATT using as a selective chalcopyrite depressant in the flotation separation of Cu/Mo ores by micro-flotation tests. Finally, the adsorption morphology of ATT depressant on chalcopyrite surface was unveiled by DFT method from a microscopic level. Through these FTIR and XPS analysis, combined with DFT simulation results, it was inferred that ATT was mainly chemically adsorbed on chalcopyrite surface by SCu and NCu bonds. These studies confirmed that ATT was very likely to be an excellent chalcopyrite depressant in Cu/Mo flotation separation.