Selective flotation separation of fluorite from calcite by application of flaxseed gum as depressant

Abstract In this study, the effect of flaxseed gum (FG) on selective flotation separation of fluorite from calcite using sodium oleate (NaOl) as collector was investigated. Micro-flotation tests demonstrated that FG could selectively inhibit the flotation of calcite but barely influence that of fluorite. Zeta potential and adsorption test indicated that large amounts of FG were adsorbed on calcite surface, while, as for fluorite, the adsorption of FG was negligible. The selective adsorption of FG would further affect the adsorption of NaOl as well as the flotation behaviour. FTIR and XPS analysis results illustrated that the carboxyl groups (–COOH) of FG could be chemically chelated with the calcium ions species of calcite surface, which further prevented the adsorption of NaOl. In this way, the effective flotation separation of fluorite from calcite could be achieved.