Kinetics of steam reforming of methane on Rh–Ni/MgAl2O4 catalyst

Abstract

The kinetics of the steam reforming of methane was studied on 0.5 wt% Rh–15 wt% Ni/MgAl2O4 catalyst. The variation of methane conversion with contact time ($${\text{W}}/{\text{F}}_{{{\text{CH}}_{4} ,0}}$$) was recorded in the temperature range of 450 to 600 °C, at three different pressures of 1, 4 and 6 bar, and at steam to carbon ratio (S/C) of 2, 5 or 6. Before the kinetic experiments, a check for external and internal mass transfer limitations was also performed. The experimentally obtained data was tested for different earlier proposed kinetic models, and parameters were calculated using non-linear least square optimization. Among the different kinetic models tested, the kinetic model proposed by Al-Ubaid and Wolf was found to be the most suitable. Reaction order of 0.21 for methane and 0.16 for water with an apparent activation energy of 75.3 kJ/mol was obtained.