L. Struble—contributing editor
Quantification of the Extent of Reaction of Metakaolin-Based Geopolymers Using X-Ray Diffraction, Scanning Electron Microscopy, and Energy-Dispersive Spectroscopy
Article first published online: 15 MAR 2011
© 2011 The American Ceramic Society
Journal of the American Ceramic Society
Volume 94, Issue 8, pages 2663–2670, August 2011
How to Cite
Williams, R. P., Hart, R. D. and van Riessen, A. (2011), Quantification of the Extent of Reaction of Metakaolin-Based Geopolymers Using X-Ray Diffraction, Scanning Electron Microscopy, and Energy-Dispersive Spectroscopy. Journal of the American Ceramic Society, 94: 2663–2670. doi: 10.1111/j.1551-2916.2011.04410.x
This project was carried out under the auspices of and with the financial support of the Centre for Sustainable Resource Processing, which was established and supported under the Australian Government's Cooperative Research Centres Program.
- Issue published online: 9 AUG 2011
- Article first published online: 15 MAR 2011
- Manuscript No. 28645. Received September 21, 2010; approved December 22, 2010.
This study presents four independent methods to determine the fraction of metakaolin dissolution in geopolymers. Two quantitative X-ray diffraction (XRD) results agreed with two independent techniques using scanning electron microscopy. The fraction of the metakaolin consumed varied from 10(8) to 75(3) wt% for geopolymers with compressive strengths varying from 3.1(2) to 67(17) MPa, respectively. It is proposed that the increase in strength with higher consumption of metakaolin is primarily due to the resultant changes in the matrix chemistry rather than changes in the quantity of matrix. Input Si/Al ratios of 1.5, 1.9, 2.5, and 3.0 resulted in matrix Si/Al ratios of 1.7, 2.3, 3.8, and 21. As anticipated the fraction of metakaolin dissolved was found to vary with OH− concentration. The area ratio method and the partial or no known crystal structure method have been identified as suitable for analysis of geopolymerization by time resolved XRD.