Aggregation/dispersion of ultrafine
silica in flotagent solution
silica in flotagent solution
(1. Department of Mineral Engineering, Central South University,
Changsha 410083, P.R.China;
2. Department of Metallurgical Engineering, University of Utah, 412 WBB,
SaltLake City, UT 84112, USA)
Changsha 410083, P.R.China;
2. Department of Metallurgical Engineering, University of Utah, 412 WBB,
SaltLake City, UT 84112, USA)
Abstract: The aggregation/dispersion of ultrafine particles is of interest for both fundamental and practical perspective. These behaviors of ultrafine silica in flotagent solution and the heter-coagulation of silica and alumina were examined using particle size analyzer, electrokinetic potential, contact angle measurements. The flotation reagents have a pronounced effect on the aggregation or dispersion behaviors of ultrafine silica suspensions. Collector dodecylamine chloride renders silica surfaces hydrophobic and the aggregation between silica particles takes place. Modifier tripolyphosphate makes the silica surface completely hydrophilic and enhances the stability of silica suspension. These experimental results can be explained based on the extended DLVO theory by considering polar interfacial interaction between particle surfaces.
Key words: aggregation; dispersion; silica; flotagent; polar interfacial interaction