Influence of calcination temperature on the structure and catalytic reforming performance of Ni/CaO-Al₂O₃ catalyst

Considering the tunable structure of hydrotalcite-like compounds, co-precipitation method was employed to synthesize Ni/CaO-Al₂O₃ composite catalysts. The influence of calcination temperature on the structure and catalytic reforming performance of Ni/CaO-Al₂O₃ catalyst investigated. The results showed that the specific surface area and Ni particle size of the as-synthesized composite catalysts were greatly affected by calcination temperature of the precursor derived from the variable interaction between the Ni and the support. When the calcination temperature was 700 ℃, the composite catalyst obtained a specific surface area of 21.42 m²/g and Ni particle size of 19.51 nm. The catalytic evaluation showed that the composite catalyst possessed a H₂ concentration of 98.31% and a CH₄ conversion of 94.87%, and H₂ concentration exceeded 97.35% even after 10 cyclic runs. The high catalytic activity was ascribed to the higher specific surface area, which provided more active sites and enhanced CO₂ sorption. The smaller Ni particle size improved the anti-sintering capacity of the composite catalyst, endowing the composite catalyst superior stability.