The effect of modifier identity on the performance of Ni-based catalyst supported on γ-Al2O3 in dry reforming of methane

Abstract

• Encapsulation of Ni metal particles within heat resistant oxide support Al 2 O 3 . • Modification of Surface by MO x (M = Ti, Mo, W, Zr, Si, B) modifier. • Re-modulation of Ni dispersion-stability, surface porosity, basicity & reducibility. • Fine correlation of activity and characterization result scopes featured industrial catalyst. Dry reforming of methane (DRM) for the production of synthesis gas (syngas: H 2 +CO) was performed over a series of nickel-based catalysts supported on γ-alumina promoted by B, Si, Ti, Zr, Mo and W. All catalysts were prepared by the wet incipient impregnation method and were characterized by X-ray diffraction (XRD), N 2 physisorption, H 2 -TPR, CO 2 -TPD, XPS, SEM and TGA. Among different catalysts investigated, 5Ni3SiAl and 5Ni3WAl catalytic systems were found highly active with excellent coke resistance in DRM, as both catalyst systems showed >64% CH 4 conversion, >70% CO 2 conversion, and >0.90 mol H 2 /CO ratio over seven hours of reaction. The strong interaction between NiO and γ-alumina support in the presence of Si or W oxide modifier (in 5Ni3SiAl or 5Ni3WAl) was indicated as the main factor positively affecting both Ni dispersion and stability.