Novel green bio-composite geopolymeric thermo-plasters for innovative building applications: upcycling spent coffee ground

This study proposes the reuse of spent coffee ground and biomass fly ash in the development of green geopolymeric thermo-plastering for innovative building applications. The former waste is the major residue of the brewing process, that is usually used as fertilisers or disposed of in landfill with extreme harmfulness for the natural environment. The latter is an industrial waste generated during the Kraft paper-pulp process, that is usually landfilled. The mortar is produced with a combination of metakaolin (30 wt.%) and biomass fly ash (70 wt.%), and natural siliceous sand filled with spent coffee ground (up to 17.5 wt.%). The high amount of reused waste makes the material an optimum cand…