Geopolymer materials: from building sector to added value materials

The versatility of geopolymer materials is well known and starting from this assumption, the research on geopolymers at CNR-ISTEC is addressed to several application sectors (Fig. 1). Regarding the building sector several foams and composite panels, for heat and sound insulation, have been produced exploiting the addition of fillers as vermiculite, perlite and waste materials as silica fume, biomass ashes, wool. These materials underlined the possibility of obtaining innovative materials thanks to the use of a wide variety of components, including recycled ones, capable of enhancing the green and eco-sustainable aspect combined with good performance. Furthermore, transports and aeronautics can enjoy of heat resistant shields [1]. In the last years, starting from benchmark geopolymer formulations new applications with high added value have been placed under investigation. Indeed, in this perspective geopolymers have recently been addressed as alternative, cost-effective, environmentally friendly adsorbents for the removal of pollutants from gaseous or liquid streams. Different production processes were applied to easily mold geopolymers into different shapes as monoliths, granules or beads for easiness of operation and to facilitate the handling and storage. The possibility to tailor the porosity and the ionic exchange and electrostatic interaction properties were exploited, together with opportunity of functionalize the matrices with fillers in order to create more performing composite materials and broaden the spectrum of applications. Geopolymer matrices and geopolymer-composites were studied as oxygen carriers as well as adsorbents for wastewater treatment and CO2 [2].