Role of Mn in the Ni–Mn/SBA-15 Catalyst for Hydrogen Production by Biomass Steam Reforming at Relatively Low Temperature

The reaction mechanism of steam reforming of cyclohexane as a model compound of tar on Ni/SBA-15 and Ni–Mn/SBA-15 catalysts was investigated by the transient technique and temperature-programmed reduction method. These catalysts were prepared by the impregnation of SBA-15 with an ethylene glycol-containing metal precursor and characterized by transmission electron microscopy (TEM), X-ray diffraction, and X-ray photoelectron spectroscopy. The spent catalysts were characterized by thermogravimetric analysis and Raman spectrometry. According to TEM analysis, it was considered that the Ni–Mn alloy state was formed on 9Ni–1Mn/SBA-15. Compared with the 10Ni/SBA-15 catalyst, the addition of Mn into Ni increased the formation of H2 because of strong interactions between Ni and Mn in the Ni–Mn alloy and acceleration of the dehydrogenation of C6H12.