Elucidating how ionic adsorption controls the rheological behavior of quartz and cement-quartz paste

This study revealed how the ionic adsorption adjusts the rheological behavior of quartz and cement-quartz paste. A series of model solutions containing different electrolytes were prepared to evaluate the influence of pH, ionic strength on zeta potential and rheological behavior of quartz. Based on the characteristics of quartz, the rheological mechanism of cement-quartz paste was interpreted. Throughout the work, it is revealed that: (1) the rheological behavior of quartz suspension is dominated by the magnitude of electric double layer (EDL) repulsion, high pH elevates the surface charge of quartz and hence decreases the viscosity of quartz suspension; (2) divalent Ca2+ and Mg2+ significantly reduced the zeta potential of quartz and increased the viscosity by compressing the EDL thickness; (3) the incorporation of quartz as filler decreased the flowability of cement paste due to excessive adsorption of Ca(2+ )and the flocculation of quartz particles. Published by Elsevier Ltd.

Automated summary

This study explores how ionic adsorption affects the rheological behavior of quartz and cement-quartz paste. The rheological behavior of quartz suspension is mainly controlled by electric double layer repulsion, with high pH reducing viscosity and divalent ions increasing it. Incorporating quartz as filler reduces the flowability of cement paste due to excessive adsorption of divalent ions and particle flocculation.