EFFECT OF ACTIVATION ON ALUMINUM RECOVERY FROM PYROPHYLLITE ORE BY ACID LEACHING

In this study, effect of activation conditions on the recovery of aluminum (Al) obtained by acid leaching from Pütürge (Malatya) pyrophyllite ore containing 23.6% Al2O3 was investigated. In this context, the initially non-activated ore and later activated ore samples using calcining and intensive milling were leached with HCl, separately. According to the experimental results, Al-recovery in the leachate for the raw, calcined and intensively milled ore samples were found to be 10.57%, 33.63% and 86.5%, respectively. It was also found that there was not sufficient dilation between the clay layers during calcination and the porous structure could not be obtained, also the new mineral phases which resist to dissolution in acidic media were formed at high temperatures. For this reason, the aluminum recovery of thermally activated ore was relatively low. However, it was confirmed that mechanical activation by intensive milling led to amorphization of clay minerals, and thus, the mechanical activation significantly improved the dissolution behavior of aluminum. As a result of this study, it is concluded that while Al recovery is slightly increased by thermal activation, it is dramatically increased by mechanical activation