Influence of deflocculant on the isoelectric point of refractory powders: Considerations on the action of deflocculant

Abstract

Isoelectric point changes in suspensions of refractory materials vis-a-vis the role of deflocculants used in monolithic refractories were investigated by considering the mineral compositions and adsorbed ions in four kinds of clay. Three types of curves represented the relation between the isoelectric point and the deflocculant. The surface charge of clay particles in the suspensions became negative as a result of the deflocculant, since the isoelectric point of suspensions decreased as the deflocculant was added. The isoelectric point changes of calcined alumina were also compared with those of the clays, and a similar phenomenon was observed, except that the deflocculant dispersed the calcined alumina better than it did the clays. A simple model was used to analyze the results