The Influence of Nano-Sio2 on the Carbonation Properties of Low Calcium CO2 Sequestration Binder and Its Mechanism

The present study focuses on the development of a Low Calcium CO2 Sequestration Binder (LCCSB) composed primarily of α-CS, C3S2, and C2AS. The carbonation properties, carbonation products, and microstructure of various nano-SiO2 (NS) were comprehensively characterized using XRD, TGA, pH, conductivity, LF NMR, and SEM techniques. The influence mechanism of incorporating NS on the carbonation reaction of LCCSB was elucidated. The findings demonstrated that the incorporation of NS enhances the carbonation performance of LCCSB, accelerates the reaction process between CO2 and minerals, promotes the generation of aragonite, and reduces porosity. The carbonation performance exhibits optimal results with an NS content of 0.06%. The results present a promising application prospect for the cement industry in the development of low calcium carbon cement.