Kinetic of methane steam reforming reaction over nickel- and rhodium-based catalysts Original Research Article

Kinetics of methane steam reforming over a commercial nickel-based catalyst and over an innovative rhodium-perovskite catalyst of formula BaRhxZr(1−x)O3 was studied at atmospheric pressure and in the temperature range 723–1023 K. Extensive experimental runs were firstly carried out in a micro-reactor, with the catalysts in powder form, to evaluate their performances in steam methane reforming process. The behaviour of rhodium-perovskite catalyst was analyzed as function of steam-to-methane ratio and temperature, comparing the obtained performances of this catalyst with that showed by the commercial nickel-based one. Rhodium-perovskite catalyst shows higher activity for steam methane reforming reaching methane conversions higher than those obtained with the nickel-based catalyst and closer to the thermodynamic equilibrium value. Based on a detailed review of the kinetic models proposed for steam reforming, the experimental data were fitted using a simple kinetic model where the conversion of methane is proportional only to the methane partial pressure. Good agreement was obtained between the experimental data and the kinetic model prediction.