Abstract:Using the Ag-bearing galena as a research object, the influence of three types of ammonium dibutyl dithiophosphate (ADD), ethyl xanthate (EX), diethyldithiocarbamate (DDTC), sodium carbonate, lime two regulators on its flotation behavior were investigated. The capture mechanism analysis was carried out by Zeta potential measurement and adsorption measurement. The results of flotation behavior show that the Ag-bearing galena is suitable for recovery in weakly alkaline medium and the upward trend is more obvious with the increase of Ag content. Compared with lime, the recovery rate of Ag-bearing galena is higher when sodium carbonate is used as regulator. Ammonium dibutyl dithiophosphate (ADD) is a good collector for recovery of Ag-bearing galena in weakly alkaline medium, and diethyldithiocarbamate (DDTC) can also be recovered in strongly alkaline medium, but the recovery rate is low. The mechanism analysis results show that, in a weakly alkaline medium, not only the negative shift of Zeta potential on the surface of ammonium dibutyl dithiophosphate (ADD) is significantly higher than that of the other two medicaments, but also the saturated adsorption capacity on the surface of Ag-bearing galena is also the largest. According to the thermodynamic method, the critical pH values for the flotation of Ag-bearing galena in the flotation of ammonium dibutyl dithiophosphate (ADD) and diethyldithiocarbamate (DDTC) are 9.27 and 10.81, respectively, which are consistent with the actual flotation law.

Key words: Ag-bearing galena; flotation; collecting mechanism; recovery rate