Effects of Na2B4O7·5H2O on the properties of foam glass from waste glass and titania-bearing blast furnace slag

Abstract Foam glass was produced by the sintered powder technology using waste glass and titania-bearing blast furnace slag with Na 2 B 4 O 7 ·5H 2 O as the flux agent at the temperature of 900 °C. CaCO 3 and Na 3 PO 4 ·12H 2 O were added as foaming agent and foaming stabilizer, respectively. The influence of the amount of Na 2 B 4 O 7 ·5H 2 O on the apparent density, water absorption, compressive strength, microstructure and crystalline phase of the foam glass was evaluated. The experimental results showed that flux agent content has a significant impact on the properties of the expanded material. The foam glass with 10 wt% Na 2 B 4 O 7 ·5H 2 O exhibited the excellent comprehensive properties at a low sintering temperature of 900 °C.