Facile Fabrication and Stable Mechanism of a Microscale Heavy Calcium Carbonate Suspension

Heavy calcium carbonate (CaCO₃) suspension is widely utilized in industrial, food, and cosmetic applications because of its advantageous physicochemical properties, abundant source, and low cost. However, its practical performance was limited because of the agglomeration issues caused by the high surface energy and inherent hydrophilicity. Herein, hydrophobic CaCO₃ was prepared via sequential modification with stearic acid and n-octyltriethoxysilane (OTES). Their oil-based homogeneous suspensions were developed to mitigate the challenges of agglomeration and sedimentation of heavy CaCO₃ particles. The systems exhibited low viscosity and high fluidity while maintaining nonsettling stability for more than 30 days with a 25% CaCO₃ loading. Concurrently, the synergistic interactions between organoclay and emulsifiers in this system established a stable suspension, with experimental validation via stability analyzer assessments delivering robust data that elucidate the internal stable structure of the system. This straightforward method offered a new perspective for utilizing microscale heavy CaCO₃ suspensions and presented a potential avenue to expand its industrial applications.