International Journal of Energy Research, Vol.42, No.13, 4120-4130, 2018
Influence of promoted 5%Ni/MCM-41 catalysts on hydrogen yield in CO2 reforming of CH4
The modern world needs to find an alternative fuel that can replace the nonrenewable fossil fuels. Being versatile, sustainable, efficient, and clean energy carrier, hydrogen has the potential to play that role. Contrasted to conventional hydrocarbon fuels, hydrogen has high energy yield per unit mass. CO2 reforming of CH4 is a progressing technology for hydrogen production. Ni promoted with Ga, Gd, Sc, Ce, or Cs supported on mesoporous silica MCM-41 catalysts were synthesized via an impregnation technique. To the best of our knowledge, the use of such promoters with Ni supported on MCMC-41 has not been yet explored in the literature. H-2-TPR, XRD, TGA, and TEM were used to characterize and explain the catalytic performance of 5%Ni+1%x/MCM-41 (x=Ga, Gd, Sc, Ce, or Cs) catalysts for the production of synthesis gas. The prepared catalysts preserved the ordered mesoporous structures of MCM-41. Promoters increased the metal-support interactions; moreover, Gd, Sc, Cs, or Ce-promoted catalysts yielded the lowest amounts of carbon deposition. Promoting with 1% of Ga, Gd, or Ce improved CH4 and CO2 conversions by 38%. On the other hand, 1% Sc or Cs reduced CH4 conversion by 18% and 93% respectively, and CO2 conversions by 16% and 92% respectively. The results showed that the maximum H-2 yield followed the order 1% Ga (90%)>1% Ce (84%)>1% Gd (74%).