Comparison of the Properties of Calcium Silicates Derived from Different Raw Materials

Abstract

The limited deposits of natural wollastonite in our country and the labor intensity of its extraction and processing, make promising the development of methods of its synthesis based on various types of domestic plant and fossil raw materials, especially industrial waste. The use of rice husk ash and calcium oxide in the solid-phase synthesis of calcium silicates ensures the content of β-wollastonite in their composition at the level of naturally-occurring Miwoll10-97. The obtained results indicate greater efficiency of amorphous silicon dioxide for the synthesis in the solid phase of calcium silicates. Synthetic calcium silicates, like naturally occurring wollastonite, have a pronounced alkaline surface nature, with the acid-base characteristics not influenced significantly by the sintering temperature, as well as the type and ratio of initial components. Calcium silicate produced from zeolite-siliceous rock has the smallest particle size and the narrowest particle size distribution, i.e. the most homogeneous structure. All investigated calcium silicates increase the wear resistance of epoxy materials, and low-porous silica sand-based fillers are more effective, providing high resistance of filled epoxy materials to climatic factors as well.

Keywords

• calcium silicates
• wollastonite
• epoxy compositions
• phase and particle size distribution
• porosity
• rice husk