Flotation separation performance of malachite from calcite with new chelating collector and its adsorption mechanism.

• The flotation performances of malachite and calcite with CMDTP were explored. • CMDTP exhibited a stronger collecting power and a better selectivity on malachite than on calcite. • Cu2+ ions could promote the floatability of calcite in the presence of CMDTP. • CMDTP could adsorb on malachite surface via chemical interactions by FT-IR, zeta potential and XPS analysis. In this study, the flotation separation performances of malachite from calcite were investigated using a new chelating collector S-carboxymethyl-O, O'-dibutyl dithiophosphate (CMDTP) by micro-flotation tests, which showed that CMDTP exhibited a stronger collecting power and a better selectivity on malachite than octyl hydroxamic acid (OHA), 8-hydroxyquinoline (HQ) and sodium isobutyl xanthate (SIBX). In the flotation separation of artificially mixed minerals, malachite could be separated successfully from calcite at pH around 9.0 when using Na 2 S as a regulator. Its adsorption mechanism was also studied by FT-IR, zeta potential and XPS measurements, all of which confirmed that CMDTP showed a better affinity to malachite surface than to calcite surface. Furthermore, XPS provided obvious evidence that CMDTP could easily react with Cu2+ sites on malachite surface, and only a tiny adsorption occurred on calcite surface without Cu2+ ions. [ABSTRACT FROM AUTHOR]