Structural Ordering of Aged and Hydrothermally Cured Metakaolin Based Potassium Geopolymers

This study evaluates the potential correlation between natural aging and hydrothermal curing (accelerated aging), related to the crystallisation of zeolites in potassium-based metakaolin geopolymer binders. 7-year old sealed-cured specimens, formulated with varying silicate contents, were evaluated. The effect of different accelerated aging durations on the mineralogy of these potassium-based geopolymers was also assessed. The results show that although zeolite formation is favoured under both natural and accelerated aging in potassium-based geopolymers, different types of zeolites are formed depending on the silicate content added to the mix, and the curing conditions of the specimens.