Influence of temperature on stability of aqueous alumina slurry containing polyelectrolyte dispersant

Effects of temperature on the stability of aqueous alumina slurry dispersed with polyelectrolyte have been studied An adsorption experiment was performed to investigate the mechanism of the temperature-dependent stability in the system. Viscosity measurement and sedimentation results show that temperature dramatically affects the stability of slurry. The adsorption of dispersant increases with increasing temperature and the stability is strongly dependent on the adsorption state. As temperature increases, more dispersant is needed to reach a new adsorption equilibrium. In low initial concentration of dispersant Iegion, the dispersant is insufficient to satisfy the increasing adsorption as temperature increases. Consequently, the apparent 'coverage declines and flocculation takes place. A stability map is established to indicate the effect of the temperature on the stability of this system. (C) 1996 Elsevier Science Limited.