Novel Preparation of Foamed Glass-ceramics from Asbestos Tailings and Waste Glass by Self-expansion in High Temperature

Abstract Foamed glass-ceramics without using foaming agents have been fabricated in the system of SiO2−MgO CaO-Fe2O3 Na2O by self-expansion during the process of powder sintering, using pre-calcined asbestos tailings and waste glass as raw materials. The effects of waste glass content and sintering temperature on phase composition, pore structure and physical properties of foamed glass-ceramic samples were systematically investigated by means of X-ray diffraction (XRD), thermogravimetry-differential scanning calorimetry analysis (TG-DSC), scanning electron microscopy (SEM) and physical properties tests, furthermore, the pore forming mechanism of samples was also expounded. The samples prepared with 67 wt.% of waste glass and sintered at 1180 °C possessed bulk density of 0.96 g•cm−3, volume expansion rate of 93%, porosity of 64% and compressive strength of 14Mpa, respectively. This study realized the utilization of asbestos tailings and waste glass, and provided theoretical and practical value for the preparation of foamed glass-ceramics without adding foaming agents.