Silicate Thermal Insulation Material from Rice Hull Ash

Silicate blocks were produced from rice hull ash (RHA) derived sodium silicate, and physical properties and thermal conductivity of the blocks were investigated. A Sodium silicate solution was produced from RHA by solublizing the silica in 1 M NaOH at 100 °C, followed by filtering to remove the carbon residue. The silicate solution was then boiled at different heating rates to evaporate the water and produce highly porous thermal insulation blocks with varying densities. X-ray diffraction patterns demonstrated the amorphous natur