Fabrication of Lightweight Foam Glasses for Thermal Insulation Applications

Abstract

Abstract Foam glasses were fabricated using glass powder obtained from consumable waste glass bottles as the main raw material. Sodium silicate was used as the binder in all mixtures. Yellow glycerol obtained from biodiesel production (contained ∼80% glycerol, 10% water, 10% methanol, fatty acids and other materials) and sodium carbonate were used as foaming agents. Factors which influenced the foaming behavior included type of foaming agent, amount of foaming agent and heating rate. These factors affected pore formation within the foam glass structure which in turn affected physical, mechanical and thermal properties of the synthesized foam glass. In this study foam glass with the most outstanding properties had thermal conductivity value of 0.260 W/mK, which was fabricated with a composition of 92 wt.% glass powder, 3.5 wt.% sodium silicate, 3.5 wt.% glycerol and 1.0 wt.% sodium carbonate. The mixture was heated at 850°C using a heating rate of 10°C /min and 30 min holding time at maximum temperature. This composition showed the average bulk density value of 0.67 g/cm3 and the highest average compressive strength value of 166 kg/cm2. Foam glasses using waste glass bottles in this study may provide a promising way to fabricate lightweight construction materials with excellent thermal insulating property.