Characterization of different types of silica-based materials

Abstract

Waste glasses based on silicon dioxide (silica) belong to one of the most demanded secondary raw materials. Besides the glass industry, with strict requirements for source materials, silica-based granular materials from waste glasses are considered suitable for use as fillers in alkali-activated cement-based composites. However, due to variations of ground waste glass powder composition and properties a comprehensive characterization is often needed. This study investigated commercially available silica-based powders by scanning electron microscopy, X-ray photoelectron spectroscopy, attenuated total reflectance Fourier transform infrared spectroscopy and Fourier transform infrared Raman spectroscopy, zeta-potential and pH measurements, etc. The differences found in the non-silica impurities composition and structure of SiO2 particles (amorphous vs crystalline) were considered as determinative factors that will affect particles’ interaction with water and cement binder. The observed results provide a fundamental background and will contribute to a better understanding and explanation of the silica-based secondary raw materials interaction reactions in concrete or mortar.