Porous Geopolymer Insulating Core from a Metakaolin/Biomass Ash Composite
AbstractAshes derived from the combustion of vegetal and animal biomass still represent a mostly unexplored secondary raw material for the production of alkali-activated materials, given their peculiar chemical nature. In this work, calcium phosphate biomass ashes were successfully used as partially reactive fillers in a metakaolin-based geopolymer composite to produce, by direct foaming, sustainable and lightweight boards with thermal insulating properties. The investigated materials were obtained by activating a blend of metakaolin and biomass ash in a weight ratio of 1: 1 and foamed with the addition of H2O2 in measure of 5 wt. %, to maximize the volume of disposed ash and ensure adequate properties to the material at the same time. The obtained geopolymer composite was characterized by microstructural, chemical-physical, mechanical and thermal analysis: the obtained results showed that biomass ash and metakaolin well integrated in the microstructure of the final porous material, which was characterized by a density of about 310 kg/m3 and a thermal conductivity of 0.073 W/mK at a mean test temperature of 30 °C, coupled with an acceptable compressive strength of about 0.6 MPa. Dilatometric and thermogravimetric analysis, performed up to 1000 °C, highlighted the thermal stability of the composite, which could be regarded as a promising material for low-cost, self-bearing thermal insulating partitions or lightweight cores for thermostructural sandwich panels. View Full-Text
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Natali Murri, A.; Medri, V.; Papa, E.; Laghi, L.; Mingazzini, C.; Landi, E. Porous Geopolymer Insulating Core from a Metakaolin/Biomass Ash Composite. Environments 2017, 4, 86.
Natali Murri A, Medri V, Papa E, Laghi L, Mingazzini C, Landi E. Porous Geopolymer Insulating Core from a Metakaolin/Biomass Ash Composite. Environments. 2017; 4(4):86.Chicago/Turabian Style
Natali Murri, Annalisa; Medri, Valentina; Papa, Elettra; Laghi, Luca; Mingazzini, Claudio; Landi, Elena. 2017. "Porous Geopolymer Insulating Core from a Metakaolin/Biomass Ash Composite." Environments 4, no. 4: 86.
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