Abstract
This study investigates the effect of silica and alumina contents on setting, phase development, and physical properties of high calcium fly ash (ASTM Class C) geopolymers. The characteristic rapid setting properties and, hence, limited workability range of high calcium fly ash geopolymers has restricted both development and potential application of these binder systems compared to conventional geopolymer binders derived from bituminous coal, i.e., (ASTM Class F) sources or from calcined kaolin feedstocks. For this study, control of setting and hardening properties were investigated by adjusting SiO2/Al2O3 ratio of the starting mix, via series of mixes formulated with varying SiO2 or Al2O3 contents to achieve SiO2/Al2O3 in the range 2.87–4.79. Foremost is the observation that the effect of varying silica and alumina in high calcium fly ash systems on setting and hardening properties is markedly different from that observed for traditional Class F geopolymer systems. Overall, increases in either silica or alumina content appear to shorten the setting time of high calcium-based systems unlike conventional geopolymer systems where increasing Al2O3 accelerates setting. The setting process was associated primarily with CSH or CASH formation. Furthermore, there appears to be a prevailing SiO2/Al2O3 ratio that prolongs setting, rather than Ca2+ ion content itself, while NASH primarily contributes to strength development. SiO2/Al2O3 ratios in the range of 3.20–3.70 resulted in products with highest strengths and longest setting times. These results suggest that initial predominance of Ca2+ ions and its reactions effectively help maintaining a SiO2/Al2O3 ratio at which amorphous geopolymer phase is stable to influence setting and initial strength development.
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Jo BW, Park SK, Park JB (2007) Cem Concr Compos 29:128
Chindaprasirt P, Jaturapitakkul C, Chalee W, Rattanasak U (2007) Waste Manage 29:539
Ahmaruzzaman M (2010) Prog Energy Combust Sci 36:327
Chindaprasirt P, Chareerat T, Hatanaka S, Cao T (2011) J Mater Civ Eng (ASCE) 23:264
Somna K, Jaturapitakkul C, Kajitvichyanukul P, Chindaprasirt P (2011) Fuel 90:2118
Temuujin J, Williams RP, Van Riessen A (2009) J Mater Process Technol 209:5276
Ravindra NT, Somnath G (2009) ARPN J Eng Appl Sci 4:68
Van Jaarsveld JGS, Van Deventer JSJ, Lukey GC (2003) Mater Lett 57:1272
Hanjitsuwan S, Chindaprasirt P, Pimraksa K (2011) Int J Miner Metall Mater 18:94
A′lvarez-Ayuso E, Querol X, Plana F, Alastuey A, Moreno N, Izquierdo M, Font O, Moreno T, Diez S, V′azquez E, Barra M (2008) J Hazard Mater 154:175
Sang-Sook P, Hwa-Young K (2008) Korean J Chem Eng 25:78
Kovalchuk G, Ferna′ndez-Jime′nez A, Palomo A (2007) Fuel 86:315
Rattanasak U, Chindaprasirt P (2009) Miner Eng 22:1073
Chindaprasirt P, Chareerat T, Sirivivatnanon V (2007) Cem Concr Compos 29:224
Guo X, Shi H, Dick WA (2010) Cem Concr Compos 32:142
Guo X, Shi H, Chen L, Dick WA (2010) J Hazard Mater 173:480
Rattanasak U, Pankhet K, Chindaprasirt P (2011) Int J Miner Metall Mater 18:364
Chindaprasirt P, Rattanasak U, Jaturapitakkul C (2011) Cem Concr Compos 33:55
Temuujin J, Riessen AV, Williams R (2009) J Hazard Mater 167:82
Yip CK, Lukey GC, Provis JL, Van Deventer JSJ (2008) Cem Concr Res 38:554
Yip CK, Lukey GC, Van Deventer JSJ (2005) Cem Concr Res 35:1688
De Silva P, Sagoe-Crenstil K, Sirivivatnanon V (2007) Cem Concr Res 37:218
Dutta D, Thokchom S, Ghosh P, Ghosh S (2010) ARPN J Eng Appl Sci 5:74
Qing Y, Zenan Z, Deyu K, Rongshen C (2007) Constr Build Mater 21:539
Garcia-Lodeiro I, Palomo A, Ferna′ndez-Jime′nez A, Macphee DE (2011) Cem Concr Res 41:923
Lecomte I, Henrist C, Li′egeois M, Maseri F, Rulmont A, Cloots R (2006) J Eur Ceram Soc 26:3789
Pardal X, Pochard I, Nonat A (2009) Cem Concr Res 39:637
Desbats-Le Chequer C, Frizon F (2011) J Mater Sci 46:5657. doi:10.1007/s10853-011-5516-6
De Silva P, Sagoe-Crenstil K (2008) Cem Concr Res 38:870
Steveson M, Sagoe-Crentsil K (2005) J Mater Sci 40:2023. doi:10.1007/s10853-005-1226-2
Acknowledgements
The financial supports from Thailand Research Fund (TRF) through the Royal Golden Jubilee Ph.D. Program (Grant No. PHD 0359/2550), the TRF Senior Research Scholar (Grant No. RTA5480004), and the Australian Catholic University are gratefully acknowledged. We are indebted to Dr. R. Wuhrer in the Mictrostructrue Analysis Unit, University of Technology Sydney for his help with the SEM analysis.
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Chindaprasirt, P., De Silva, P., Sagoe-Crentsil, K. et al. Effect of SiO2 and Al2O3 on the setting and hardening of high calcium fly ash-based geopolymer systems. J Mater Sci 47, 4876–4883 (2012). https://doi.org/10.1007/s10853-012-6353-y
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DOI: https://doi.org/10.1007/s10853-012-6353-y