Effects of olive oil on physical and mechanical properties of ceramic waste-based geopolymer foam

The present study concentrated on porous geopolymer composites (between calcined clay and metakaolin) using hydrogen peroxide as a pore generation agent. To reduce as well as recycle the waste from a factory, calcined clay waste was used as starting material. The geopolymer was synthesized via a geopolymerization method by a reaction with an alkaline solution, using the ceramic waste and metakaolin as raw materials. Different amount of olive oil (0–15 wt%) were added to the samples. The olive oil affected the pore formation of the geopolymers. The effects of olive oil, a surfactant, on the properties of the geopolymer composites were investigated. Apparent density and compressive strength of the samples tended to decrease with the additive, while water absorption and total porosity had the opposite effect. However, a variation in the apparent density and water absorption values was observed, due to the formation of closed pores in the samples. The trend of compressive strength value was related with total porosity. A model for pore formation was proposed in this work. The results suggest that this material can be used as a geopolymer foam.