Recycling of waste flat glass in the fabrication of Si3N4 powder by the carbo‐thermal reduction and nitridation

Abstract

AbstractThe recycle rate of waste flat glass is quite low in spite of higher SiO2 content and its pre‐melted characteristic. This study searched a novel approach for the fabrication of Si3N4 powder by carbo‐thermal reduction and nitridation from waste glass. For comparison, starting powder mixtures were prepared from silica and waste SLS (soda‐lime‐silica) glass. Carbo‐thermal reduction and nitridation process was conducted using two temperatures and different atmospheres. The results showed that equiaxed, micron size β‐Si3N4 particle could be synthesized from waste glass. The use of waste glass reduced the amount of fiber‐like Si3N4 particles and SiC phase by increasing the amount of the liquid phase formed. This study proved the utilization of waste flat glass as a low cost and environment friendly SiO2 source.