The influence of reaction stoichiometry on aluminium phosphates formed by dehydration on processing, product and thermal stability

This paper investigates the elevated temperature stability of aluminium phosphates synthesized with varying precursor molar ratios. Several studies have previously been conducted on both experimental and theoretical product formation of different precursor molar ratios, however there is substantial variances across the results. This research aims to define the differences in product formation caused by the reaction stoichiometry followed by an assessment of product thermal stability up to 1500 °C via Simultaneous Thermal Analysis, STA. The change in precursor molar ratio demonstrated an impact on product formation over the course of the reaction, including a change in detected reaction products and bond types studied by X-Ray Diffraction, XRD, Particle Size Analysis, PSA, and Fourier Transform Infrared Spectroscopy, FTIR and qualitatively confirmed by SEM and EDX. The final products were processed into hydrogels and clear variations in thermal stability above 600 °C were observed.