Steam Methane Reforming over Ni-based Pellet-type and Pt/Ni/Al2O3 Structured Plate-type Catalyst: Intrinsic Kinetics Study

Intrinsic kinetics study of steam methane reforming (SMR) was performed on two different systems-commercial Ni-based pellet catalyst and Pt/Ni/Al2O3 structured plate catalyst. Experiments were carried out in the absence of external mass transfer resistance, and temperature 500-575 degrees C, pressure 2.5-7.5 bar, and H2O/CH4 reactant ratio range of 3-5 mol/mol. Reactors operated in the integral mode, and it was shown that both systems could be described by the same kinetics, based on Langmuir-Hinshelwood mechanism. In the case of plate catalyst, the regeneration treatment after deactivation led to platinum particle redispersion, which further influenced the values of the pre-exponential factors, whereas the activation energy values remained unchanged. Comparison of the two catalyst systems was made based on the active metal content, and it was shown that the catalytic activity of the Pt/Ni/Al2O3 plate catalyst after the second regeneration treatment was 8 times of that observed for the Ni-based pellet catalyst.