Hydrothermal synthesis of β-dicalcium silicate (β-Ca2SiO4)

β-Dicalcium silicate (β-Ca2SiO4) 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 CaCO3. 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 B2O3 as a stabilizer. Possible causes of high reactivity have been discussed.