Thermocatalytic decomposition of methane presents a promising approach for hydrogen (H2) production alongside solid carbon, offering a viable alternative to conventional methods such as steam methane reforming while circumventing CO2 emissions. Utilizing carbon catalysts helps alleviate deactivation concerns attributed to coking, particularly prevalent in metal-based catalysts. This project focuses on investigating catalytic methane pyrolysis across three scales: the molecular, the particle, and the reactor scale. Innovative ordered mesoporous carbon catalysts will be designed and tested, after which a microkinetic analysis will be performed to gain insights into the reaction mechanism and aid in identifying the active sites. At the particle scale, the multi-grain model is employed to incorporate coke formation into heat and mass transfer equations, facilitating formulation of a growth model. Complementing these mathematical formulations, an experimental campaign is conducted to track catalyst weight changes and electrical conductivity during methane pyrolysis. Subsequently, within a newly developed electrothermal fluidized-bed reactor (ETFB), the project examines the electromagnetic field's influence on fluidization behavior and pyrolysis chemistry. Various process parameters such as electrical power, fluidization velocity, particle diameter, and bed composition are systematically assessed using a combination of experimental observations and modelling techniques.