Syngas production from methane dry reforming via optimization of tungsten trioxide-promoted mesoporous γ-alumina supported nickel catalyst

Abstract

Syngas production via dry reforming of methane was conducted over 5 wt%Ni + xWO3/γ-Al2O3 (x = 1, 3, 5, 7, or 9 wt%) catalysts at 700 °C and ambient pressure for 7.5 h in a tubular fixed-bed reactor. Textural, morphological, and catalytic properties were investigated in relation to the weight percent of tungsten trioxide loading. The physicochemical properties of the catalysts were evaluated using XRD, N2-physisorption, TGA, H2-TPR, CO2-TPD, NH3-TPD, SEM, EDX, and Raman techniques. N2-physisorption analysis showed that tungsten trioxide promoter had a minor impact on the textural properties upon varying its weight percentage loading. With increasing tungsten trioxide loading, the total amount of reducible NiO-interacting species was increased over the catalyst surface. 5Ni+5WO3/γ-Al2O3 catalyst showed stable 79% CH4 conversions and 83% CO2 conversion with the lowest carbon deposition due to the presence of stable metallic Ni species (derived from reducible NiAl2O4 and NiWOAl), the highly acidic sites, and moderate basic sites.