Surface composition, charge and texture of active alumina powders recovered from aluminum dross tailings chemical waste

Three different methods were successfully applied to recover alumina (Al2O3) powders from aluminum dross tailings chemical waste (ADT) and Bauxite (BUX) ore. The six powder samples thus obtained were examined by X-ray diffractometry and photoelectron spectroscopy, zeta-potential measurement, N-2 Sorptometry and transmission electron microscopy (TEM). The results obtained revealed that alumina powders recovered from the chemical waste also assume catalytic-grade properties; viz., gamma-structured bulk, pure surfaces having a net zero charge at pH = 8.3-9.2 and apparently uniform mesopores with apparent pore diameters in the range 60-70 Angstrom. Thus, the present investigation presents an adequate utilization of the aluminum dross tailings chemical waste, which is, to date, neither adequately utilized nor properly dispensed in developing countries. (C) 2003 Elsevier Science B.V. All rights reserved.