Amine flotation of soluble sulfate salts

摘要

The sign of the surface charge for K_2SO_4 andNa_2SO_4 (anhydrous and decahydrate) in their saturated brineshas been determined by nonequilibrium laser-Dopplerelectrophoretic mobility measurements. Both K_2SO_4 andNa_2SO_4 (anhydrous and decahydrate) were found to benegatively charged. Room temperature (26 deg C) flotation ofK_2SO_4 and Na_2SO_4 10H_2O was possible with dodecylamine, but amine flotation of anhydrous Na_2SO_4 was notpossible at room temperature. In contrast, at a slightly highertemperature (40 deg C) anhydrous Na_2SO_4 could be floatedwith dodecyl amine whereas Na_2SO_4 10H_20 could not befloated. These experimental results are explained based on thethermal stability of the respective salts and the nature of theamine adsorption reaction is discussed.