Selective flotation of Cu-Mo sulfides using dithiothreitol as an environmental-friendly depressant

A small non-toxic compound dithiothreitol (DTT) was introduced as an environmental-friendly chalcopyrite depressant in Cu-Mo flotation separation. The separation performances were studied via flotation tests. The adsorption mechanism was explored by contact angle, Zeta potential and X-ray photoelectron spectroscopy (XPS) measurements. The flotation results manifested that DTT exhibited strong depression ability on chalcopyrite, but barely influenced the floatability of molybdenite. The contact angle and Zeta potential measurements indicated that DTT mainly adsorbed on chalcopyrite and rendered its surface hydrophilic, while it hardly adsorbed on molybdenite. XPS analysis confirmed that DTT might complex with Cu atoms on chalcopyrite surfaces via the thiol groups. This study demonstrated that DTT was a promising alternative for Na 2 S in Cu-Mo separation, which was more effective and environmentally compatible.