Crystallization Characteristics and Properties of Glass Ceramics Derived from Iron Tailing

In this study, iron tailings were used as raw materials mixing with Al 2 O 3 , SiO 2 , and/or CaO sintered at 950–1400 °C to produce glass ceramics. In Al 2 O 3 /tailing and Al 2 O 3 /SiO 2 /tailing systems, the newly formed crystalline mullite (3Al 2 O 3 ·2SiO 2 ) reached its maximum content of 83.7 wt% for sample with Al 2 O 3 /SiO 2 /tailing mass ratio of 6/2/2. In Al 2 O 3 /SiO 2 /CaO/tailing system, the content of newly formed anorthite (CaAl 2 Si 2 O 8 ) increased to the maximum of 72.9 wt% for sample with Al 2 O 3 /SiO 2 /CaO/tailing mass ratio of 7/8/4/6 sintered at 1450 °C. The properties of glass ceramic products were significantly improved in samples with high content of crystalline mullite or anorthite and low surface porosity. Obtained glass ceramic in Al 2 O 3 /SiO 2 /tailing system with mass ratio of 6/2/6 showed excellent properties of chemical resistance (99.99%), compressive strength (1061.6 MPa), and low water absorption (0.2%). The high performance of glass ceramics and low leachability of hazardous metals shed light on the potential application of iron tailings in building and decorative materials. Graphical Abstract