Comparative study of modified Ni catalysts over mesoporous CaO-Al₂O₃ support for CO₂/methane reforming

Promoted (ceria, lanthana, and yttria)-Ni/CaO-Al₂O₃ catalysts were prepared and after characterizing by XRD, BET, TPR, TEM, TPO, and FE-SEM tests, evaluated in CO₂/methane reforming (CRM) process. The observations revealed that the catalyst redox properties, crystallite size, and dispersion are important factors in catalytic performance. Among promoted Ni catalysts, the ceria-promoted catalyst with the smallest crystallite size (8.9 nm), the largest specific surface area and total pore volume showed the highest catalyst activity (~81%). Moreover, the TPO and FE-SEM of used catalysts demonstrated the lower CNT deposited on the ceria-promoted catalyst surface that leads to a delay in catalyst deactivation.