Investigating the Geopolymerization Process of Aluminosilicates and Its Impact on the Compressive Strength of the Produced Geopolymers
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Investigating the Geopolymerization Process of Aluminosilicates and Its Impact on the Compressive Strength of the Produced Geopolymers

Authors: Heba Z. Fouad, Tarek M. Madkour, Safwan A. Khedr


This paper investigates multiple factors that impact the formation of geopolymers and their compressive strength to be utilized in construction as an environmentally-friendly material. Bentonite and Kaolinite were thermally calcinated at 750 °C to obtain Metabentonite and Metakaolinite with higher reactivity. Both source materials were activated using a solution of sodium hydroxide (NaOH). Thereafter, samples were cured at different temperatures. The samples were analyzed chemically using a host of spectroscopic techniques. The bulk density and compressive strength of the produced geopolymer pastes were studied. Findings indicate that the ratio of NaOH solution to source material affects the compressive strength, being optimal at 0.54. Moreover, controlled heat curing was proven effective to improve compressive strength. The existence of characteristic Fourier Transform Infrared Spectroscopy (FTIR) peaks at approximately 1020 cm-1 and 460 cm-1 which correspond to the asymmetric stretching vibration of Si-O-T and bending vibration of Si-O-Si, hence, confirming the formation of the target geopolymer.

Keywords: alcination of metakaolinite, compressive strength, FTIR analysis, geopolymer, green cement

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[1] N. A. Farhan, M. N. Sheikh and M. N. S. Hadi, "Investigation of engineering properties of normal and high strength fly ash based geopolymer and alkali-activated slag concrete compared to ordinary Portland cement concrete," Construction & Building Materials, vol. 196, pp. 26-42, January 2019.
[2] P. Duxson et al, "Geopolymer technology: the current state of the art," Journal of Materials Science, vol. 42, (9), pp. 2917-2933, 2007.
[3] I. García-Lodeiro, N. Cherfa, F. Zibouche, A. Fernandez-Jimenez, A. Palomo. "The role of aluminium in alkali-activated bentonites," Materials and Structures, vol. 48, (3), pp. 585-597, March 2015
[4] A. Fernández-Jiménez et al, "Alkaline activation of metakaolin–fly ash mixtures: Obtain of Zeoceramics and Zeocements," Microporous and Mesoporous Materials, vol. 108, (1), pp. 41-49, 2008.
[5] D. L. Y. Kong, J. G. Sanjayan and K. Sagoe-Crentsil, "Factors affecting the performance of metakaolin geopolymers exposed to elevated temperatures," Journal of Materials Science, vol. 43, (3), pp. 824-831, February 2008.
[6] B. Kenne Diffo, A. Elimbi, M. Cyr, J. Dika Manga, H. Tchakoute Kouamo, “Effect of the rate of calcination of kaolin on the properties of metakaolin-based geopolymers”, Journal of Asian Ceramic Societies, vol. 3, (1), pp. 130-138, 2015,
[7] P. Rovnaník, "Effect of curing temperature on the development of hard structure of metakaolin-based geopolymer," Construction & Building Materials, vol. 24, (7), pp. 1176-1183, January 2010.
[8] F. G. M. Aredes et al, "Effect of cure temperature on the formation of metakaolinite-based geopolymer," Ceramics International, vol. 41, (6), pp. 7302-7311, February 2015.
[9] J. W. Phair, J. D. Smith and J. S. J. Van Deventer, "Characteristics of aluminosilicate hydrogels related to commercial “Geopolymers”," Materials Letters, vol. 57, (28), pp. 4356-4367, 2003.
[10] C. A. Rees et al, "Attenuated Total Reflectance Fourier Transform Infrared Analysis of Fly Ash Geopolymer Gel Aging," Langmuir, vol. 23, (15), pp. 8170-8179, 2007.
[11] X. Yao, Z. Zhang, H. Zhu, Y. Chen, "Geopolymerization process of alkali–metakaolinite characterized by isothermal calorimetry," Thermochimica Acta, vol. 493, (1), pp. 49-54, 2009.
[12] T. Kosor, B. Nakić-Alfirević and A. Gajović, "Geopolymerization index of fly ash geopolymers," Vibrational Spectroscopy, vol. 85, pp. 104-111, 2016.
[13] M. Criado, A. Fernández-Jiménez and A. Palomo, "Alkali activation of fly ash. Part III: Effect of curing conditions on reaction and its graphical description," Fuel (Guildford), vol. 89, (11), pp. 3185-3192, 2010.
[14] G. Fang, W. K. Ho, W. Tu, M. Zhang, "Workability and mechanical properties of alkali-activated fly ash-slag concrete cured at ambient temperature," Construction & Building Materials, vol. 172, pp. 476-487, 2018.
[15] C. Y. Heah et al., "Study on solids-to-liquid and alkaline activator ratios on kaolin-based geopolymers," Construction & Building Materials, vol. 35, pp. 912-922, 2012.
[16] H. Wang, H. Li and F. Yan, "Synthesis and mechanical properties of metakaolinite-based geopolymer," Colloids and Surfaces. A, Physicochemical and Engineering Aspects, vol. 268, (1), pp. 1-6, 2005.
[17] Q. Wan et al, "Geopolymerization reaction, microstructure and simulation of metakaolin-based geopolymers at extended Si/Al ratios," Cement & Concrete Composites, vol. 79, pp. 45-52, 2017.
[18] A. Autef et al, "Role of the silica source on the geopolymerization rate," Journal of Non-Crystalline Solids, vol. 358, (21), pp. 2886, 2012.
[19] M. Criado, A. Palomo and A. Fernández-Jiménez, "Alkali activation of fly ashes. Part 1: Effect of curing conditions on the carbonation of the reaction products," Fuel (Guildford), vol. 84, (16), pp. 2048-2054, 2005.
[20] M. R. Rowles and B. H. O'Connor, "Chemical and Structural Microanalysis of Aluminosilicate Geopolymers Synthesized by Sodium Silicate Activation of Metakaolinite," Journal of the American Ceramic Society, vol. 92, (10), pp. 2354-2361, 2009.
[21] B. R. Bickmore, K. L. Nagy, A. K. Gray, A. R. Brinkerhoff, "The effect of Al(OH)4− on the dissolution rate of quartz," Geochimica Et Cosmochimica Acta, vol. 70, (2), pp. 290-305, 2006.
[22] S. Hanjitsuwan et al, "Effects of NaOH concentrations on physical and electrical properties of high calcium fly ash geopolymer paste," Cement & Concrete Composites, vol. 45, pp. 9-14, 2014.