Kinetic modeling of oxidative dehydrogenation of propane with CO<sub>2</sub> over MoO<sub><i>x</i></sub>/La<sub>2</sub>O<sub>3</sub>–Al<sub>2</sub>O<sub>3</sub> in a fluidized bed
Majid L. Balogun, Yahya Gambo, Sagir Adamu, Mohammed S. Ba‐Shammakh, Mohammad M. Hossain
Abstract
Abstract A 4‐step kinetic model of CO 2 ‐assisted oxidative dehydrogenation (ODH) of propane to C 2 /C 3 olefins over a novel MoO x /La 2 O 3 –γAl 2 O 3 catalyst was developed. Kinetic experiments were conducted in a CREC Riser Simulator at various reaction temperatures (525–600 °C) and times (15–30 s). The catalyst was highly selective towards propylene at all combinations of the reaction conditions. Langmuir‐Hinshelwood type kinetics were formulated considering propane ODH, uni‐ and bimolecular cracking of propane to produce a C 1 ‐C 2 species. It was found that the one site type model adequately fitted the experimental data. The activation energy for the formation of propylene (67.8 kJ/mol) is much lower than that of bimolecular conversion of propane to ethane and ethylene (303 kJ/mol) as well as the direct cracking of propane to methane and ethylene (106.7 kJ/mol). The kinetic modeling revealed the positive effects of CO 2 towards enhancing the propylene selectivity over the catalyst.