Single-step solid-state synthesis and characterization of Wollastonite-2M by rice husk ash

The present work deals with the single-step solid state synthesis of Wollastonite-2M using rice husk ash and natural limestone as starting materials. Solid phase reaction synthesis is performed at 1000 °C and ambient pressure by mixing 3 g of rice husk ash and 3g of limestone. The X-ray diffraction pattern after 4 h sintering shows that only wollastonite-2M is detected as single phase. Scanning electron microscopy reveals acicular-needle shaped crystals (8 μm long and ∼0.5 μm wide). Infrared and Raman spectroscopy characterizations confirm the achievement of the phase. The purity of the synthesized Wollastonite-2M is evaluated through estimation of the amorphous phase by means of quantitative phase analysis using the combined Rietveld and reference intensity ratio methods, resulting in a final product of 85.2 % Wollastonite-2M.