Selectivity in the flotation of copper with xanthate over other ions present in wastewater: An experimental and computational study

In this work, molecular modeling simulations are used to study the flotation process of copper, cadmium and zinc ions present in wastewater, acid mine drainage and others, with xanthate collector. Simulations were conducted by DFT technique, with M06 functional at 6-31G(d,p)/LanL2DZ level. Characterizations of the molecular and electronic structures of the complexes formed applying NPA, AIM and CLPO analysis of the coordination bonds show the kind of main interactions between metals and the ligand. Results confirm the experimental evidence and show the ability of this technique to study this process. The interaction energy of the studied complexes is -56,39 kcal/mol for Cu, -25,86 kcal/mol for Cd and -7,29 kcal/mol for Zn complex. It was found that xanthate binds to copper over zinc and cadmium elements. Experimental results show that for copper, cadmium and zinc, the flotation effectiveness are 94,68%; 67,18% and 36,92% respectively. (C) 2020 Elsevier Inc. All rights reserved.