Kinetics study of geopolymerization of fly ash using isothermal conduction calorimetry

Isothermal conduction calorimetry has been used to study the reaction kinetics of early geopolymerization of fly ash. Fly ash particles were subjected to react with NaOH solution in 2:1 ratio at isothermal temperatures of 34, 39, 45, 52, and 60 °C. The reaction kinetic parameters such as activation energy, rate of reaction, and pre-exponential function were calculated using the rate of heat evolution data. It is observed that the geopolymerization reaction followed a nucleation and growth mechanism. The activation energy obtained from an Arrhenius plot was around ~100 kJ mol^?1.