Enrichment of titanium dioxide in red mud: a kinetic study

A process is described for the enrichment of titanium dioxide in red mud. T he procedure employed is leaching the red mud with hydrochloric acid follow ed by roasting the leached residue with sodium carbonate. The kinetics of l eaching of various constituents of red mud were obtained experimentally in a stirred batch reactor. The variables include acid to mud ratio and temper ature. The data obtained were analysed using the shrinking core model and J ander's equation. The effect of roasting time and temperature on percentage dissolution of alumina in leached residue was studied using a full factori al search and optimized conditions were obtained. (C) 1999 Elsevier Science B.V. All rights reserved.