Evaluation of diatomite substitute with thermal power plant waste fly ash in sustainable geopolymer through life cycle assessment


İLKENTAPAR S., Örklemez E., DURAK U., Gülçimen S., BAYRAM S., Uzal N., ...More

Journal of Material Cycles and Waste Management, vol.27, no.3, pp.1418-1435, 2025 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 27 Issue: 3
  • Publication Date: 2025
  • Doi Number: 10.1007/s10163-025-02184-w
  • Journal Name: Journal of Material Cycles and Waste Management
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, ABI/INFORM, Agricultural & Environmental Science Database, Compendex, Environment Index, INSPEC, Pollution Abstracts, Civil Engineering Abstracts
  • Page Numbers: pp.1418-1435
  • Keywords: Diatomite and fly ash, Geopolymer, Life cycle assessment, Microstructure, Strength, Sustainability
  • Abdullah Gül University Affiliated: Yes

Abstract

This research demonstrates the potential of diatomite as a fly ash replacement to improve mechanical properties and environmental sustainability and presents it as a viable alternative for sustainable construction. Additionally, a life cycle assessment (LCA) was conducted on the produced mortars to quantitatively compare their environmental impacts using a cradle-to-gate approach. In mixtures, it was used by replacing the diatomite in the ratios of 1%, 2%, 3%, 4%, and 5% by weight of the fly ash. Workability, unit weight, flexural and compressive strength, abrasion resistance, elevated temperature resistance and microstructure analysis were carried out. The results indicated that replacing 1%, 2%, and 3% diatomite increased the compressive and flexural strength of mortars due to their higher specific surface area. Two percent replacement of diatomite provided the best results. FESEM results of 3% diatomite inclusion showed more intense and compact microstructure of geopolymer. Diatomite inclusion increased the abrasion resistance of geopolymer. Since 2% diatomite replacement was found to be optimum, the LCA results showed that geopolymer mortar with 2% diatomite has 25% lower impacts in terms of global warming potential and 10% lower impacts in terms of terrestrial ecotoxicity than conventional Portland cement mortar.