| The flotation experiments of Ag-bearing galena were carried out using three sulphides as ore collectors, ammonium dibutyl dithiophosphate (ADD), ethyl xanthate (EX) and diethyldithiocarbamate (DDC), and the flotation mechanism was simulated based on the density functional theory. Flotation experiments show that Ag-bearing galena is more suitable for flotation in weak alkaline pulp with pH 9.5 compared with strong alkaline pulp, and that ammonium dibutyl dithiophosphate has better selectivity and collecion for Ag-bearing galena. The harvesting mechanism results show that the band gap of Ag-bearing galena is narrower than that of ideal galena, and that the 4d orbitals of Ag atoms are added near the Fermi energy level. It implies that Ag-bearing galena has stronger electrochemical reaction activity. According to the frontline orbital theory, when ammonium dibutyl dithiophosphate and ethyl xanthate are used as collectors, the frontier orbital effective mass of Ag-bearing galena is lower, indicating that Ag-bearing galena is easier to adsorb with these two collectors. With the increase of silver content, the effective mass of frontier orbitals in the adsorption process decreases significantly, which also indicates that silver atoms can enhance the adsorption process between collectors and mineral surfaces. The molecular dynamics simulation results show that the adsorption energy of ammonium dibutyl dithiophosphate on the surface of Ag-bearing galena is the lowest, indicating that ammonium dibutyl dithiophosphate has the best selectivity to Ag-bearing galena. |
