Separation of dolomite from phosphate minerals by flotation with a new amphoteric surfactant as collector

Abstract

Commercial-grade dodecyl-N-carboxyethyl-N-hydroxyethyl-imidazoline, a new amphoteric surfactant, has been found to be a good collector for the separation of dolomite and phosphate by flotation. Studies conducted with pure natural phosphate and dolomite minerals showed the effects of the dissolved species and temperature on the selectivity of this collector to be negligible. A phosphate concentrate containing 0.5% MgO and 32.2% P2O5 was obtained from a mixture of natural pure phosphate and dolomite minerals containing 10.2% MgO and 24.1% P2O5 at a recovery of 88% when the new collector was added at the rate of 400 g/t. Another phosphate concentrate containing 0.8% MgO and 31.2% P2O5 was obtained at a recovery of 82% from a natural ore containing 13.9% MgO and 23.5% P2O5.