Influence of Fe2O3, MgO and Molarity of NaOH Solution on the Mechanical Properties of Fly Ash-Based Geopolymers

Brăduț Alexandru Ionescu; Mihail Chira; Horațiu Vermeșan; Andreea Hegyi; Adrian-Victor Lăzărescu; Gyorgy Thalmaier; Bogdan Viorel Neamțu; Timea Gabor; Ioana Monica Sur

doi:10.3390/ma15196965

Influence of Fe₂O₃, MgO and Molarity of NaOH Solution on the Mechanical Properties of Fly Ash-Based Geopolymers

Materials (Basel). 2022 Oct 7;15(19):6965. doi: 10.3390/ma15196965.

Authors

Brăduț Alexandru Ionescu^{1

2}, Mihail Chira¹, Horațiu Vermeșan³, Andreea Hegyi¹, Adrian-Victor Lăzărescu¹, Gyorgy Thalmaier³, Bogdan Viorel Neamțu³, Timea Gabor³, Ioana Monica Sur³

Affiliations

¹ NIRD URBAN-INCERC Cluj-Napoca Branch, 117 Calea Floresti, 400524 Cluj-Napoca, Romania.
² IOSUD UTCN Doctoral School, Technical University of Cluj-Napoca, 15 Daicoviciu Street, 400020 Cluj-Napoca, Romania.
³ Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103-105 Muncii Boulevard, 400641 Cluj-Napoca, Romania.

Abstract

The use of waste from industrial activities is of particular importance for environmental protection. Fly ash has a high potential in the production of construction materials. In the present study, the use of fly ash in the production of geopolymer paste and the effect of Fe₂O₃, MgO and molarity of NaOH solution on the mechanical strength of geopolymer paste are presented. Samples resulting from the heat treatment of the geopolymer paste were subjected to mechanical tests and SEM, EDS and XRD analyses. Samples were obtained using 6 molar and 8 molar NaOH solution with and without the addition of Fe₂O₃ and MgO. Samples obtained using a 6 molar NaOH solution where Fe₂O₃ and MgO were added had higher mechanical strengths compared to the other samples.

Keywords: Fe2O3; MgO; compressive strength; geopolymer.

Grants and funding

This research received no external funding.