Effects of Rare Earth and Alkali Promoters on Distribution Profile and Properties of Spherical Shaped γ‐ Al 2 O 3 Supported Ni Catalysts

ABSTRACT This study investigates the effects of rare‐earth (La and Ce) and alkali (Mg and K) promoters on the distribution profile and properties of spherical γ‐Al 2 O 3 supported Ni catalysts. The catalysts were synthesized via sequential wet impregnation, targeting 10 wt.% Ni, with individual and co‐promotion of promoters. The distribution profiles of Ni within the spherical support revealed that promoter addition caused a NiO concentration gradient along the spherical catalysts. Characterization techniques such as X‐ray diffraction (XRD), BET (Brunauer–Emmet–Teller), scanning electron microscope & energy dispersive X‐ray spectroscopy (SEM–EDX), scanning/transmission electron microscope (S/TEM), and temperature programmed reduction (TPR) demonstrated that promoter addition significantly influenced the distribution profile, particle size, and reducibility of NiO. According to the obtained results, catalysts co‐promoted with La and Mg achieved a homogeneous distribution profile and the lowest reduction temperature, indicating enhanced Ni reducibility and potentially improved catalytic performance. These findings highlight the critical role of promoters as well as co‐promotion in modifying the active metal distribution and properties of Ni/γ‐Al 2 O 3 catalysts.