Regeneration of bifunctional Fe/C catalyst for microwave-assisted methane pyrolysis by coke gasification with CO2

• Catalyst regeneration via coke gasification (CG) extends catalyst lifespan • Thermodynamic calculations show equilibrium concentrations during CG by CO 2 and H 2 O • Reaction order for CG with CO 2 on the Fe/C catalyst is 1 • Activation energy for CG by CO 2 on the Fe/C catalyst is 183 kJ/mol Methane pyrolysis (MP) is an attractive method for producing H 2 without emitting CO 2 . However, the widespread adoption of MP is hindered by catalyst coking, which leads to catalyst deactivation. To extend catalyst lifespan, periodic regeneration is required. Based on thermodynamic calculations, CO 2 was selected as the gasifying agent, as gasification with H 2 O can lead to CO 2 emissions through a secondary water-gas shift reaction. The experiments were performed in a thermogravimetric analyser coupled with a micro GC. The chemical reaction was examined within a temperature range of 880-960 °C, and CO 2 partial pressures between 851 Pa and 4412 Pa. The volume reaction model was applied to model coke gasification. Based on statistical analysis of the results, a reaction order was found to be n=1.04±0.102, which aligns with the value reported in the literature. The activation energy was determined to be approximately 183 kJ/mol.