Towards microwave-assisted methane pyrolysis. Kinetic investigations of a Fe/C catalyst using thermogravimetric analysis coupled with gas chromatography

Methane pyrolysis (MP) is one of enabling technologies in the economy transition from fossil to renewable fuels. Although the technology has its undoubted advantages, the cost of producing hydrogen with MP is still higher than that using Steam Methane Reforming (SMR). Remote and contactless catalyst heating by microwaves can significantly intensify methane pyrolysis and reduce these costs. One of the catalysts that can be utilized in the microwave-assisted MP is the Fe/C catalyst. The current work presents a reference study of the MP kinetics on the dedicated Fe/C catalyst under conventional (non-microwave) heating. The kinetic data determined in this work are necessary for appropriate modelling and design of the microwave-assisted MP reactor. Experiments were carried out using thermogravimetric analysis coupled with gas chromatography. The reaction order with respect to methane and the activation energy were found to be 0.6, and 71 kJ/mol, respectively. The effects of CO₂ concentration and temperature on the regeneration of the catalyst were also demonstrated.