Hydrothermal synthesis of β-dicalcium silicate (β-Ca 2SiO 4)

Abstract

β-Dicalcium silicate (β-Ca 2SiO 4) has been prepared by hydrothermal method. Aerosil, rice husk ash and aerosol containing 10 wt% fly ash were used as sources of silica for reaction with freshly prepared CaO obtained from the decomposition of CaCO 3. β-Dicalcium silicates obtained by hydrothermal method were characterized by X-ray diffraction, DSC and SEM techniques. Hydration reactions were monitored by measuring non-evaporable water contents, free lime and compressive strength values. The extent of hydrations was found to be much higher as compared to that of β-dicalcium silicate prepared in a conventional manner using B 2O 3 as a stabilizer. Possible causes of high reactivity have been discussed.