Bi-reforming of Methane with Carbon Dioxide and Steam on Nickel-Supported Binary Mg-Al Metal Oxide Catalysts

Bi-reforming of methane (CH4) with carbon dioxide (CO2) and steam is a promising process to produce syngas with a H-2/CO ratio of about 2, which can be directly used as a feedstock for methanol synthesis. This work studied nickel nanoparticles supported on the binary Mg-Al metal oxide catalysts for the bireforming of CH4. The XRD, TEM, and FT-IR results confirm the successful synthesis of Ni/MgO, Ni/MgxAlyO, and Ni/Al2O3 catalysts. The TPR profile shows that the reduction temperature of Ni species was slightly decreased upon addition of Al due to the formation of the NiAl2O4 phase. The XPS spectra demonstrate that Ni/MgO and Ni/Al2O3 exhibit higher amounts of Ni-0 after H-2 reduction. It can explain the origin of the superior catalytic performance of Ni/MgO and Ni/Al2O3 over the Ni/MgxAlyO catalysts possessing less Ni-0 species during the H-2 reduction process. Compared to the conventional dry reforming of CH4, the bi-reforming process features a higher CH4 conversion and a H-2/CO ratio close to 2, which is suitable for methanol synthesis without further separation and adjustment steps.