Abstract
The catalytic methane decomposition to produce carbon oxides-free hydrogen and carbon nanomaterial is a promising method feasible for larger production at a moderate cheap price. The produced hydrogen is refined and can be employed straight in fuel cell and in petrochemical industries to produce ammonia and methanol. Auto-thermal reforming of natural gas, partial oxidation, steam reforming are the conventional techniques for hydrogen production in industry, though these processes incur excessive costs for the purification of hydrogen from producing carbon oxides. Current research work on thermo-catalytic methane decomposition has concentrated on promoting the catalytic activity and stability for simultaneous production of pure hydrogen and elemental carbon. The carbon is generated as nanotubes, which are important for the use of this material in numerous new technologies. In the present review, thermodynamics of methane catalytic decomposition are elaborated and extensive considerations are given to the development of catalyst components by emphasizing the role of active particles, effect of catalyst promoters and support. The role of carbon catalyst in decomposing the methane catalytically, the morphology and characteristics of carbon produced and the catalyst deactivation is also discussed. The review also sheds light on the influence of operating parameters of temperature and space velocity. The performances of the frequently used catalysts are tabulated and types of reactors, influences of supports, promoters and preparation methods are outlined. Finally, the iron catalyst perspective towards hydrogen and carbon nanotubes productions by means of catalytic methane decomposition is presented in this work.