EFFECT OF DIFFERENT POLYHYDROXYLIC DISPERSANTS ON DISPERSION STABILITY OF KAOLIN PARTICLES

Abstract

Controlling of ceramic properties is considered as one of the important steps that has to be taken. This has been carried out using different hydroxyl compounds as dispersants for two types of Sudanian kaolin, Merkhiat and J. Umm Ali. They were glycerin, glycerin jelly, poly(ethylene glycol) and Arabic gum. The dispersion stability was examined using sedimentation test under gravity in aqueous medium. It was found that good dispersions were obtained. Most of the kaolin particles settled as good deflocculated suspensions, whereas aggregation was much easier with kaolin suspension having no dispersant. This was reflected on the final packing density of the sediments. It was also found that the type of dispersant and its concentration have an influence on the final packing density. Arabic gum and Merkhiat kaolin were the best.