Review of methane catalytic cracking for hydrogen production

Abstract

Methane catalytic cracking is a process by which carbon monoxide-free hydrogen can be produced. Despite the fact that hydrogen produced from methane cracking is a pure form of hydrogen, methane cracking is not used on an industrial scale for producing hydrogen since it is not economically competitive with other hydrogen production processes. However, pure hydrogen demand is increasing annually either in amount or in number of applications that require carbon monoxide-free hydrogen. Currently, hydrogen is produced primarily via catalytic steam reforming, partial oxidation, and auto-thermal reforming of natural gas. Although these processes are mature technologies, CO is formed as a by-product, and in order to eliminate it from the hydrogen stream, complicated and costly separation processes are required. To improve the methane catalytic cracking economics, extensive research to improve different process parameters is required. Using a highly active and stable catalyst, optimizing the operating conditions, and developing suitable reactors are among the different areas that need to be addressed in methane cracking. In this paper, catalysts that can be used for methane cracking, and their deactivation and regeneration are discussed. Also, methane catalytic cracking kinetics including carbon filament formation, the reaction mechanisms, and the models available in the literature for predicting reaction rates are presented. Finally, the application of fluidized beds for methane catalytic cracking is discussed.