Suitability of Malaysian Fly Ash for Geopolymer Synthesis
Fly ash is a pozzolanic material which is produced during coal combustion in thermal power plants. This paper investigates the suitability of Malaysian fly ash for geopolymer synthesis. Chemical composition analysis, particle size analysis, amorphous and crystalline phases present, bonding nature, and microstructural behavior are used to determine the suitability of fly ash for geopolymer synthesis. The results showed that fly ash contains silica, alumina, ferrous oxide, and calcium oxide in major proportions which are the main ingredients required for geopolymer synthesis. Higher portion of particles having size in the range of 1-15 µm. Fly ash contains quartz, mullite, and ferrite as the crystalline compounds while the major portion of fly ash is in amorphous form. The band due to asymmetric stretching vibration mode of Si-O-T appears at 1095 cm-1 which is the main band used to follow geopolymer formation. Microstructure of fly ash shows that the higher portion of fly ash is in amorphous form while it contains cenospheres, magnetic spheres, carbon, and a large number of small particles. Malaysian fly ash is a suitable material for geopolymer and it can be used for geopolymer synthesis.