Effect of oxygen addition to steam and dry reforming of methane on bed temperature profile over Pt and Ni catalysts

The effect of oxygen addition to the steam and dry reforming of methane on the temperature profile of the fixed catalyst bed was investigated over Pt/Al₂O₃, Ni/Al₂O₃ with various metal loadings and commercial steam reforming Ni catalyst. The temperature profile of the catalyst bed was much dependent on the kind of metal and its loading. Especially the Pt/Al₂O₃ with higher loading than 1.2×10^-5 mol/g-cat gave the flat temperature profile and high methane conversion. From the profiles of bed temperature measurements under various reaction conditions, one sees that the distance between the combustion and reforming zones becomes very short. This is related to the high reducibility of Pt metal itself, and Pt maintains metallic state in the combustion zone even under the presence of oxygen. In this case, the heat of combustion can be supplied to the reforming reaction effectively. On the other hand, Ni/Al ₂O₃ and commercial steam reforming catalyst gave high temperature at the catalyst bed inlet, and this indicates that the reaction zones exist separately.