A Study on Influence of Different Counterions on Coagulation and Particle Size of Colloidal Silica

摘要

We report the influence of different counterions on coagulation and particle size of silica sol under different ionic strength respectively. The coagulation and particle size of silica sol have been determined by capillary viscometer measurements and titration method. It is found that the coagulation and particle size of silica sol are all concerned with the size of counterions, and the attraction between counterions and surface of silica sols. The small counterions may increase the growth of particles, but larger weakly acidic counterions decrease the growth of particle, and easily make sols coagulate. A discussion on influence of temperature on the stability and particle size was also performed.