CALCIUM SILICATE CARBONATION PRODUCTS

Calcium silicates such as C3S, beta-C2S, and gamma-C2S dagger were carbonated under saturated humidity at room temperature. Carbonation products were examined by DT-TGA, gasphase mass spectroscopy, and XRD. Two types of carbonate were produced: one type, which was rather poorly crystallized, was decarbonated at a very low temperature, below 600 degrees C; the other type was a crystalline phase such as calcite, aragonite, and/or vaterite which was decarbonated above 600 degrees C. The data mere compared to existing data for calcium carbonates and basic calcium carbonates. The results suggest that an amorphous calcium silicate hydrocarbonate was one of the carbonation products which formed during the hydration/carbonation reaction.