Dispersion of ultrafine alumina in modifier solution —the role of polar interfacial interaction

来源期刊：中南大学学报(英文版)2001年第1期

论文作者：HU Yue-hua QIU Guan-zhou J. D. Miller

文章页码：18 - 23

Key words：dispersion; alumina; modifier; polar interfacial interaction; extended DLVO theory

Abstract: Dispersion of ultrafine alumina suspension is examined by using particle size analyzer. The zet potential and contact angle measurementswere used to discuss the electrokinetic behavior and surfacewettability of alumina in modifier solution, and to calculate the electrostatic interaction forces and interfacial interaction forces between alumina particles. The aggregation of ultrafine alumina occurs near its PZC. Addition ofmodifier increases the zeta potential of alumina and its surface hydrophilicity, resulting in increase of electrostatic anhydration repulsion. It makes the suspension of ultrafine alumina completely dispersed. The average particlsize of the suspension is decreased from 1.73μm in absence of modifier to 0.8μm in the presence otripolyphosphate. According to polar interfacial interaction approach, the hydration forces responsible for thstability of alumina suspension in the presence ofmodifierhave also been obtained. The extended DLVOtheor is successful to describe the dispersion behavior of ultrafine alumina in modifier solution.