A Taguchi Approach for the Synthesis Optimization of Metakaolin Based Geopolymers

Abstract:

There are several factors that affect geopolymerization, including the type and ratios of the starting materials as well as the curing conditions of the initial mixture. The effect of the synthesis parameters on the formation of inorganic polymers are usually examined by “changing one factor at a time”. In this study Taguchi experimental designing model was applied in order to study the synergetic effect of selected synthesis parameters on the compressive strength development of metakaolin based geopolymers. The experimental design involved the variation of three control factors in five levels. The selected factors and the corresponding level range were: i) the alkali to aluminum molar ratio in the starting mixture (0.5-1.5), ii) the kind of alkali ion (Na and/or K) and iii) the molar ratio of Si to alkali oxide in the activation solution (0-2.0). The compressive strength of geopolymers was measured and the final products were also examined by means of XRD, FTIR and SEM. As it is concluded, the optimal synthesis conditions for metakaolin geopolymers are R/Al=0.75, Na/(Na+K)=0.50 and [Si]/R2O=1.50, while the factor having the highest impact on the development of compressive strength is the [Si]/R2O ratio.

• Periodical: Advances in Science and Technology (Volume 92)
• Pages: 44-49
• DOI: https://doi.org/10.4028/www.scientific.net/AST.92.44
• Online since: October 2014
• Authors: Alexandros Tsitouras, Sotirios Tsivilis, Glykeria Kakali*
• Keywords: Compressive Strength, Geopolymer, Metakaolin (MK), Taguchi

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