Effect of Calcination Temperature on the Structural and Textural Properties of MgAl₂O₄ Spinel Supports Synthesized by the Solution Combustion Method

In this study, MgAl₂O₄ spinel supports were synthesized via the solution combustion synthesis (SCS) method and subsequently calcined at 700, 800, and 900 °C to investigate the effect of calcination temperature on their structural and physicochemical properties. Thermogravimetric analysis (TGA) revealed the multi-step decomposition behavior of the precursor, while Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) confirmed the progressive formation and crystallization of the spinel phase with increasing temperature. Textural properties obtained from Brunauer-Emmett-Teller (BET) surface area measurements, together with morphological observations from field-emission scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (FESEM-EDS) and transmission electron microscopy (TEM), demonstrated significant variations in particle size, morphology, and surface area across the calcination series. Among the examined temperatures, the support calcined at 800 °C exhibited the most favorable balance between crystallinity, particle size, and textural properties. These findings highlight the tunability of MgAl₂O₄ spinel supports through thermal treatment and provide essential insights for their use as robust support materials in catalytic CO₂ conversion and methanation processes.