Rheological behavior of clay water slurry in the presence of cationic surfactants and Electrolytes

Abstract

The rheological properties have been studied in the presence of different additives like surfactant and electrolyte. The effect of solid concentration in bentonite-water slurry was studied. Without any additives bentonite-clay suspension behaved as a rheopectic fluid and its viscosity increased with clay concentration and time at constant shear rate. The addition of electrolytes like NaCl, Na2SO4, CaCl2 were altered the rheological properties of clay-water suspension. It was found that viscosity decreases with electrolyte concentration. The effect of cationic cetyl trimethyl ammonium bromide (CTAB) on the rheological behaviors of bentonite-water slurry was also investigated. For CTAB initially viscosity decreased with concentration, then increased till a certain value and after that viscosity decreased. The combined effect of both electrolyte and CTAB at different concentration of each was also studied. These combinations had more reducing effect on viscosity than each of the individuals’ effect on slurry viscosity. The zeta-potential values of bentonite water slurry at different pH and in the presence of different concentration of CTAB were studied. All the experiments were carried out at 30oC using a water circulator