Processing of Highly Porous Glass Ceramic from Glass and Fly Ash Wastes

摘要

This study aims to prepare a highly porous glass ceramic from a combination of soda-lime-silicate glass and fly ash waste. Commercial silicon carbide is used as a foaming agent to stimulate porous structure. The starting materials were milled individually, mixed and compacted by using uniaxial hydraulic press machine. The effects of sintering temperature and holding time on the physical-mechanical properties, morphology and crystallization were investigated. The results suggested that increasing sintering temperature from 925 °C to 975 °C and holding time from 10 min to 60 min gradually increase the pore size and pores transform from closed, isolated and fairly homogenous to open, interconnected and inhomogeneous. As a result, bulk density and compressive strength were significantly deteriorated, however apparent porosity and water absorption were noticeably increased. The variation of sintering temperature and holding time did not have any meaningful effect on the types of crystal phases formed and its intensity.