Natural pozzolan-and granulated blast furnace slag-based binary geopolymers

• Published in: Materiales de construcción (Madrid) 2016-01, Vol.66 (321), p.e077-e077
• Main Authors: Robayo, R. A., Mejía de Gutiérrez, R., Gordillo, M.
• Format: Article
• Language: English
• Subjects: alkaline-activated cement; Aluminum oxide; Ambient temperature; Blast furnace practice; blast furnace slag; Blast furnace slags; Cement; characterization; Compressive strength; Curing; Fourier transforms; Geopolymers; Granulation; Infrared spectroscopy; Pastes; Portland cements; Pozzolans; Raw materials; Reaction kinetics; Researchers; Scanning electron microscopy; Silicon dioxide; Statistical analysis; Studies; volcanic pozzolan; X-ray diffraction
• ISSN: 0465-2746; 1988-3226
• DOI: 10.3989/mc.2016.03615

This study describes the synthesis at ambient temperature (25±3 °C) of binary geopolymer systems based on natural volcanic pozzolan and granulated blast furnace slag. Na2SiO3 and NaOH were used as alkaline activators. The effects of the SiO2/Al2O3, Na2O/Al2O3 ratio and the amount of slag added (from 0 to 30%) on the reaction kinetics, compressive strength and microstructure of the final product were studied. To characterise the geopolymer pastes, techniques such as X-ray diffraction (XRD), infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used. The results indicate the possibility of obtaining a geopolymer cement with a compressive strength of up to 48.11 MPa after 28 days of curing at ambient temperature whose characteristics are comparable to those of commercial portland cement.