Kinetic study of methane reforming with carbon dioxide over NiCeMgAl bimodal pore catalyst

The kinetic behavior of NiCeMgAl bimodal pore catalyst for methane reforming with CO2 was investigated after the elimination of external and internal diffusion effects in a fixed-bed reactor as a function of temperature and partial pressures of reactants and products. Increase in CO2 partial pressure favors the consumptions of CH4 and CO2 but inhibits the formation of H2 due to the existence of reverse water gas shift (RWGS) reaction. The reforming rate increased first and then reached a horizontal stage with the rise of CH4 partial pressure. A Langmuir–Hinshelwood model was developed assuming that the carbon deposition is ignorable but the RWGS reaction is non-ignorable and the removal of adsorbed carbon intermediate is the rate-determining step. A nonlinear least-square method was applied to solve the kinetic parameters. The derived kinetic expression fits the experimental data very well with a R2 above 0.97, and also predicts the products flow rate satisfactorily. © 2016 American Institute of Chemical Engineers AIChE J, 63: 2019–2029, 2017