Synthesis of Wollastonite Powders by Combustion Method: Role of Amount of Fuel

Abstract

The objective of this work has been the synthesis of wollastonite by solution combustion method. The novelty of this work has been obtaining the crystalline phase without the need of thermal treatments after the synthesis. For this purpose, urea was used as fuel. Calcium nitrate was selected as a source of calcium and colloidal silica served as a source of silicon. The effect of the amount of fuel on the combustion process was investigated. Temperature of the combustion reaction was followed by digital pyrometry. The obtained products were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and specific surface area. The results showed that the combustion synthesis provides nanostructured powders characterized by a high surface area. When excess of urea was used, wollastonite-2M was obtained with a submicronic structure.