This paper investigates the properties of geopolymer obtained by alkali-activation of fly ash (FA), i.e. the influence of characteristics of the representative group of FA (class F) from Serbia, as well as that of the nature and concentration of various activators on mechanical and microstructural properties of geopolymers. Aqueous solutions of Ca(OH)(2), NaOH, NaOH + Na2CO3, KOH and sodium silicate (water glass) of various concentrations were used as alkali activators. It was established that the nature and concentration of the activator was the most dominant parameter in the alkali-activation process. In respect of physical characteristics of FA, the key parameter was fineness. The geopolymer based on FA with the highest content of fine particles ( lt 43 mu m), showed the highest compressive strength in all cases. Regardless of FA characteristics, nature and concentration of the activator, the alkali-activation products were mainly amorphous. The formation of crystalline phases (zeol...ites) occurred in some cases, depending on the reaction conditions. The highest compressive strength was obtained using sodium silicate. Together with the increase of sodium silicate SiO2/Na2O mass ratio, the atomic Si/Al ratio in the reaction products was also increased. Under the experimental conditions of this investigation, high strength was directly related to the high Si/Al ratio.
Keywords:
Geopolymer / Fly ash / Alkali activation
Source:
Journal of Hazardous Materials, 2010, 181, 1-3, 35-42
TY - JOUR
AU - Komljenović, Miroslav M
AU - Baščarević, Zvezdana
AU - Nikolić, Violeta
PY - 2010
UR - http://rimsi.imsi.bg.ac.rs/handle/123456789/430
AB - This paper investigates the properties of geopolymer obtained by alkali-activation of fly ash (FA), i.e. the influence of characteristics of the representative group of FA (class F) from Serbia, as well as that of the nature and concentration of various activators on mechanical and microstructural properties of geopolymers. Aqueous solutions of Ca(OH)(2), NaOH, NaOH + Na2CO3, KOH and sodium silicate (water glass) of various concentrations were used as alkali activators. It was established that the nature and concentration of the activator was the most dominant parameter in the alkali-activation process. In respect of physical characteristics of FA, the key parameter was fineness. The geopolymer based on FA with the highest content of fine particles ( lt 43 mu m), showed the highest compressive strength in all cases. Regardless of FA characteristics, nature and concentration of the activator, the alkali-activation products were mainly amorphous. The formation of crystalline phases (zeolites) occurred in some cases, depending on the reaction conditions. The highest compressive strength was obtained using sodium silicate. Together with the increase of sodium silicate SiO2/Na2O mass ratio, the atomic Si/Al ratio in the reaction products was also increased. Under the experimental conditions of this investigation, high strength was directly related to the high Si/Al ratio.
PB - Elsevier, Amsterdam
T2 - Journal of Hazardous Materials
T1 - Mechanical and microstructural properties of alkali-activated fly ash geopolymers
EP - 42
IS - 1-3
SP - 35
VL - 181
DO - 10.1016/j.jhazmat.2010.04.064
ER -
@article{
author = "Komljenović, Miroslav M and Baščarević, Zvezdana and Nikolić, Violeta",
year = "2010",
abstract = "This paper investigates the properties of geopolymer obtained by alkali-activation of fly ash (FA), i.e. the influence of characteristics of the representative group of FA (class F) from Serbia, as well as that of the nature and concentration of various activators on mechanical and microstructural properties of geopolymers. Aqueous solutions of Ca(OH)(2), NaOH, NaOH + Na2CO3, KOH and sodium silicate (water glass) of various concentrations were used as alkali activators. It was established that the nature and concentration of the activator was the most dominant parameter in the alkali-activation process. In respect of physical characteristics of FA, the key parameter was fineness. The geopolymer based on FA with the highest content of fine particles ( lt 43 mu m), showed the highest compressive strength in all cases. Regardless of FA characteristics, nature and concentration of the activator, the alkali-activation products were mainly amorphous. The formation of crystalline phases (zeolites) occurred in some cases, depending on the reaction conditions. The highest compressive strength was obtained using sodium silicate. Together with the increase of sodium silicate SiO2/Na2O mass ratio, the atomic Si/Al ratio in the reaction products was also increased. Under the experimental conditions of this investigation, high strength was directly related to the high Si/Al ratio.",
publisher = "Elsevier, Amsterdam",
journal = "Journal of Hazardous Materials",
title = "Mechanical and microstructural properties of alkali-activated fly ash geopolymers",
pages = "42-35",
number = "1-3",
volume = "181",
doi = "10.1016/j.jhazmat.2010.04.064"
}
Komljenović, M. M., Baščarević, Z.,& Nikolić, V.. (2010). Mechanical and microstructural properties of alkali-activated fly ash geopolymers. in Journal of Hazardous Materials
Elsevier, Amsterdam., 181(1-3), 35-42.
https://doi.org/10.1016/j.jhazmat.2010.04.064
Komljenović MM, Baščarević Z, Nikolić V. Mechanical and microstructural properties of alkali-activated fly ash geopolymers. in Journal of Hazardous Materials. 2010;181(1-3):35-42.
doi:10.1016/j.jhazmat.2010.04.064 .
Komljenović, Miroslav M, Baščarević, Zvezdana, Nikolić, Violeta, "Mechanical and microstructural properties of alkali-activated fly ash geopolymers" in Journal of Hazardous Materials, 181, no. 1-3 (2010):35-42,
https://doi.org/10.1016/j.jhazmat.2010.04.064 . .
