Synthesis, hydration and thermal stability of hydrates in strontium-aluminate cement

The synthesis of strontium aluminate cement, the course of hydration and the thermal stability of hydrates are described in this work. The activation energy of the process of SrAl2O4 formation was calculated using the model-free Kissinger kinetic equation. The synthesis of the main clinker phase required the activation energy of 218 kJ mol−1. The value of kinetic exponent was corresponded to the process controlled by increasing nucleation rate of a new phase. For the hydration of strontium aluminate cement an immediate and intensive evolution of heat without any measurable induction period is typical. The cubic tri-strontium aluminate hexahydrate (Sr3AH6) and alumina gel (AH3) phases were formed as the first and also the main hydration products. The formations of strontium aluminate heptahydrate (SrAH7) and gibbsite (γ-AH3) were recognized after 7th day of hydration process.