Characteristics of Australian brown coal fly ash blended geopolymers

Abstract

The present study evaluates the potential re-use options for a suite of low rank brown coal fly ashes (ASTM class C fly ash) as feedstock for geopolymer binder synthesis. Ash suitability was evaluated using a number of conventional characterisation tools including XRF, calorimetric and microscopy to analyse solid phase distribution in relation to compositional differences derived from ternary diagram analogues. Blends of brown coal ash with selected black coal fly ash (class F) and blast furnace slag were developed for compressive strength and durability tests. The study show that brown coal fly ash with higher Al content improved the rate of reaction of blended binders and that observed hig..