Muduli et al
Greener Journal of Physical Sciences Vol. 3 (6), pp. 204-211, October 2013.
ISSN: 2276-7851 © 2011 Greener Journals
Manuscript Number: 280913874
Effect of NaOH Concentration in Manufacture of Geopolymer Fly Ash Building Brick
*S.D. Muduli, J.K. Sadangi, B.D. Nayak, and B.K. Mishra
CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, Odisha.
*Corresponding Author’s Email: surabhidipali @ gmail. com
Geopolymerization is a non-fired process of chemical
reaction between silica, alumina, calcium, magnesium, iron
bearing constituents of the material under alkaline
condition to form hydrous structures of rock forming
silicate minerals. In this research work geopolymerization
technology was used for utilization of industrial solid
wastes like fly ash in manufacture of high strength building
brick. In this process, sodium based alkaline activator (pH
> 11.5) consisting of anions of Cl- and SO4˭ of different
concentrations in presence of water had been used for
reaction of silica and silicates to develop a stable and
solidified geopolymer structure by curing below 20oC and
also at normal atmospheric temperature of 35OC. The raw mix
consisting of 87% of fly ash and alkaline activator had been
used by maintaining Na2O/(Al2O3+SiO2) ratio of 0.025 to
0.078 to manufacture building materials ranging in crushing
strength of 6 to 48 MPa.
Keywords: Alumino-silicate polycondensation; exothermic reaction process; mineral dissolution; silicon-oxygen tetrahedral.