Collect. Czech. Chem. Commun. 1989, 54, 91-101

Ultrafiltration of silica sols

Milan Stakić, Slobodan Milonjić, Vladeta Pavasović and Zoja Ilić

The Boris Kidrič Institute of Nuclear Sciences, P.O. Box 522, 11001 Belgrade, Yugoslavia


Ultrafiltration of three laboratory made silica and two commercial silica sols was studied using Amicon YC membrane in a 200 ml capacity batch-cell. The effect of silica particle size, stirring conditions, pressure, pH and silica contents on ultrafiltration was investigated. The results obtained indicate that the smaller particles have, disregarding the stirring conditions, lower filtration flux. The differences observed in filtration flux are more pronounced in the conditions without stirring. The obtained value of the membrane resistance is independent of the conditions investigated (stirring, pressure, pH, silica contents and particle size). The values of the resistance of polarized solids, specific resistance, and the mass of gel per membrane surface unit were calculated for all experimental conditions.