Ultrafine wet grinding of corundum in the presence of triethanolamine

Abstract

The aim of this work is to study changes in the properties of aqueous corundum suspensions during ultrafine grinding with and without the addition of an activator. Corundum suspensions were prepared in distilled water in a ratio of 1:5 with and without the addition of triethanolamine (TEA) and ground using a planetary ball mill. Particle-size distribution, ζ-potential, rheological behavior and turbidity were then measured. TEA was not proved to be a suitable activator for wet grinding of corundum as finer products were obtained in grinding without it. The suspensions showed pseudoplastic behavior and the ζ-potential of all samples ranged from −30 to +30 mV, so the suspensions were unstable. During grinding, the originally negative ζ-potential was converted to positive values and the viscosity and turbidity of the samples increased.