Dicalcium silicate (2CaO·SiO2) synthesized through flame spray pyrolysis and solution combustion synthesis methods

Abstract

Synthesis of dicalcium silicate (2CaO.SiO2 or C2S) through flame spray pyrolysis and a solution combustion method was investigated by the variation of flames and fuels. The synthesized powders were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and scanning electron microscopy (SEM). X-ray diffraction analysis revealed the formation of dicalcium silicate polymorphs with presence of calcium oxide, calcium carbonates and amorphous materials as impurities. Results suggest that some flames and fuels favor the formation of calcite during the synthesis process due to an excess of carbon atoms in the combustion. Fourier transform infrared spectra of all samples showed the main silicates reflections located near to 500 cm−1 and 1000 cm−1 and scanning electron microscopy showed the formation of spherical agglomerates of nanoparticles in both methods. By these two alternative methods of synthesis it was possible to obtain C2S with nanometric particle size.