Abstract: A Ni/MgO catalyst was prepared using atmospheric high frequency discharge plasma jet. The influence of three preparation methods, the conventional method, plasma method, and plasma plus calcination method, on the catalyst activity was compared using CO₂ reforming with methane as the probe reaction. The catalyst samples were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and CO₂ temperature-programmed surface reaction. The results suggested that the Ni-based catalyst sample prepared by the plasma plus calcination method possessed smaller Ni particle size, higher dispersion of active components, higher low-temperature activity, and enhanced anti-coking ability. The conversions of CO₂ and CH₄ were 90.70% and 89.37%, respectively, and lasted for 36 h without obvious deactivation under 0.1 MPa, 36 L/(h·g) and 750 ^oC with n(CH₄)/n(CO₂) = 1.

Key words: nickel, magnesium oxide, carbon dioxide, methane, reforming, atmospheric high frequency discharge plasma jet