Dry reforming reactions offer an opportunity for the catalytic conversion of light alkanes into synthesis gas. Ni-based catalysts are promising due to their high activity and low cost, but they suffer from poor stability caused by coke formation and metal sintering. In this study, we synthesized a series of Ni-based spinel oxides (Ni/MgAl
2O
4, Ni/CoAl
2O
4, Ni/ZnAl
2O
4, and Ni/FeAl
2O
4) through impregnation method for dry reforming of methane at 800°C. Among these catalysts, the Ni/MgAl
2O
4 catalyst exhibited higher activity and better stability when using a stoichiometric feed ratio (1:1). The MgAl
2O
4 spinel layer effectively suppressed the phase transformation into NiAl
2O
4 spinel phases while stabilizing well-dispersed tiny crystallites of Ni, contributing to the good stability of the catalyst.
Reactor simulation results revealed that adding an inert diluent significantly improved the performance of the Ni/MgAl2O4 catalyst by reducing temperature gradient in the catalyst bed. We carried out an experiment by adding SiO2 as an inert diluent and found that using a ratio of 1:3 for Ni/MgAl2O4:SiO2 improved its performance by approximately 15%. Based on these findings, we desired to optimize the performance of catalyst from the point of view of reaction engineering. We designed a flat plate monolithic catalyst named Ni-MgAl2O4/carbon foam which demonstrated superior catalytic activity and stability under 800°C .
