Effect of crystallization temperature on glass-ceramics derived from tailings waste

Abstract

Abstract Sintered glass-ceramics containing CaO–Al2O3–SiO2 were successfully fabricated by application of sinter-crystallization process, with tungsten tailings waste (TTW) as main raw materials. Crystallization kinetics analysis showed that surface crystallization dominated the overall crystallization process and the ingredient of TTW was beneficial to the crystallization process. The effects of crystallization temperature on crystallization behavior and properties of glass-ceramics demonstrated that it played an important role in controlling the crystal growth and crystalline phase transition. With the increasing crystallization temperature to 1050 °C, part of the crystalline phase was transformed from wollastonite to anorthite. Also, the glass-ceramic fired at 950 °C for 2 h presented higher volumetric density (2.82 g/cm3), lower water absorption (0.09%), higher flexural strength (97.56 MPa), superior Vickers hardness (6.3 GPa), moderate acid resistance (0.18%), and lower alkali resistance (0.19%). Leaching tests performed on as-prepared glass-ceramics demonstrated that heavy metals were stabilized well in the newly formed phase. Overall, the glass-ceramics derived from TTW are promising for exploring high value-added products and vitrifying hazardous elements, as well as promoting their application in construction and environmental protection.