Sustainable environment approach by the usage of ceramic pottery waste in geopolymer mortar

This study aims to evaluate the pottery waste obtained from a pottery company in Cappadocia (Turkey) in the production of geopolymer mortars (GMs), which is becoming increasingly interesting in construction technology. For this purpose, mortars were prepared by replacing the fly ash with pottery wastes at proportions of 0%, 10%, 20%, 30%, and 40% by weight. Flow table, water absorption, apparent porosity, flexural strength, compressive strength, and high-temperature resistance tests were applied to GMs. Diopside, calcium silicate hydrate, and wollastonite crystals were observed in phase analyses performed by XRD for mortar containing 40% pottery waste. The observed microstructure analysis of before and after high-temperature tests was performed to investigate the effect of pottery waste on GMs. Consequently, better results were obtained at high-temperature strength up to 800 °C compared to the reference (0% pottery waste) by replacing up to 40% of fly ash with pottery waste to improve the physical and mechanical properties. Pottery waste replacement enhanced the flexural strength and compressive strength at 28 days by up to 26% and 64%, respectively, compared to reference mortar at ambient conditions. Furthermore, considering the overall mechanical and microstructural analysis, GMs with pottery waste promise sustainable mortar production and waste elimination. The pottery waste is a potential alternative material to be successfully recycled in the eco-friendly geopolymer mortars as a replacement of fly ash up to 40% level.