Selective depression of galena by sodium polyaspartate in chalcopyrite flotation

Abstract

• PASP (Sodium polyaspartate) is a kind of biodegradable and available polyamino acid. • PASP can depress the flotation of galena under weakly alkaline conditions. • PASP has a greater impact on galena than on chalcopyrite . • The competitive adsorption on the mineral surface results in the selective depression. In the flotation separation of copper-lead–zinc complex polymetallic sulphide ores, the separation of chalcopyrite from galena is difficult because both of them have good floatability. Therefore, the development of a green, eco-friendly and selective galena depressant is highly required. In this work, sodium polyaspartate (PASP) was used as a galena depressant in the separation of chalcopyrite from galena. Single mineral flotation experiments showed that PASP could selectively depress galena. With 10 mg/L PASP addition at pH = 10, the recovery of chalcopyrite remained 91.9%, but the recovery of galena decreased to 1.1%. The selective depression mechanism of PASP was studied by collector adsorption measurements, FT-IR and XPS analysis.