Depression mechanism of the zinc sulfate and sodium carbonate combined inhibitor on talc

Abstract

Abstract Solution chemical calculation, zeta potential measurement and flotation test were introduced to verify the effective inhibiting component and illustrate the inhibition mechanism of ZnSO 4 and Na 2 CO 3 as a combined inhibitor for talc. Solution chemical speciation calculations indicated that the formation of solid state Zn(OH) 2 occurred in all initial concentration ranges of ZnSO 4 . The higher the initial concentration was, the lower the pH values were when solid state Zn(OH) 2 appeared. The solid state ZnCO 3 formed when the initial concentrations of ZnSO 4 were higher than 1 × 10 −4 mol/L, and the formation was qualified in certain concentration ranges of Na 2 CO 3 . Additionally, the ranges extended with the increasing initial concentration of ZnSO 4. Along with the results of the zeta potential measurement and flotation test, it demonstrated that the effective inhibiting components of the combined inhibitor were solid state ZnCO 3 and Zn(OH) 2 , while ZnCO 3 played a major role. When the combined inhibitor is used for the depression of talc, the addition of Na 2 CO 3 and initial concentration of ZnSO 4 should be strictly controlled at a restricted level that is suitable for the formation of solid state ZnCO 3 . ZnSO 4 and Na 2 CO 3 is an effective combined inhibitor for talc in flotation separation of talc and molybdenite.