Activation energy approach for alkali-activated glass inorganic binders in different aging conditions

Abstract

In this study, waste glass was alkali-activated by activators with different amounts of sodium hydroxide and subjected to aging. The chemical reactions and resulting microstructures and properties of the alkali-activated glass inorganic binders (AAGIBs) were affected by aging temperature and duration. An activation energy approach was employed to evaluate the effects of aging temperature and duration on the 4-day compressive strengths of the AAGIB specimens. When the amount of sodium hydroxide in the activators was low, the activation energies for the dissolution and polycondensation reactions of the AAGIBs were 83.3 and 44.6 kJ/mol, respectively. As AE% in the activators increased, the microstructure of the hardened binder became destroyed because of vigorous stirring during aging. Consequently, the activation energy of the AAGIB polycondensation reaction increased to 76.2 kJ/mol when AE% greater than 5%.