Evaluation of the Mechanical and Thermal Properties of Sustainable Geopolymer Mortars Incorporating Olive Seed Ash and Date Seed Ash

Akram Q. Moften; Dhuha Ahmed Abd Al Sattar

doi:10.18011/bioeng.2026.v20.1310

Authors

Akram Q. Moften Department of Materials Engineering, Mustansiriyah University, Baghdad, Iraq https://orcid.org/0009-0001-4975-073X
Dhuha Ahmed Abd Al Sattar Department of Materials Engineering, Mustansiriyah University, Baghdad, Iraq https://orcid.org/0009-0004-7215-9026

DOI:

https://doi.org/10.18011/bioeng.2026.v20.1310

Keywords:

Sustainable materials, Date Seeds Ash, Olive Seeds Ash, Thermal Conductivity, Agricultural waste

Abstract

This study explores the use of Date Seeds Ash (DSA) and Olive Seeds Ash (OSA) as partial replacements for fly ash (FA) in geopolymer mortar to promote sustainable alternatives to Ordinary Portland Cement. Mortar mixtures were prepared with 5, 10, 15, and 20 wt.% of DSA and OSA. The mechanical (compressive and flexural strength), physical (bulk density), and thermal (thermal conductivity) properties were evaluated. Results showed that increasing DSA/OSA content led to a gradual decrease in strength and bulk density, mainly due to the higher porosity and lower pozzolanic activity of the ashes compared to FA. However, this increased porosity improved thermal insulation by reducing thermal conductivity. Overall, DSA and OSA demonstrated potential as eco-friendly additives in geopolymer mortars, contributing to waste utilization and carbon emission reduction in the construction sector.

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