Methane Cracking: A Comprehensive Review of Catalysts, Solar Reactors, and Integrated System Case Studies

This study provides a comprehensive review of the methane cracking process, with a focus on integrating solar energy and exploring various catalyst systems. Different types of solar reactors are examined, including indirectly radiated, directly radiated, and catalyzed reactors, as well as solar energy collection methods. Bench-scale reactors and demonstrations show promising results but require scale-up studies and suffer from carbon clogging issues. Catalysts for methane cracking face rapid deactivation due to carbon coking. The development of stable and affordable catalysts is essential for the long-term success of this process. Two integrated systems are proposed and evaluated thermodynamically. In System 1, carbon and hydrogen produced from solar methane cracking are used for electricity generation in fuel cells. The system achieves an energy efficiency of 41.9% and an exergy efficiency of 52.3%, with methanol and DME being produced via CO2 hydrogenation. In System 2, photovoltaic energy powers a co-electrolyzer for syngas production, which is then used to synthesize methanol fuel. This system shows energy and exergy efficiencies of 40.6% and 37.5%, respectively. Both systems demonstrate reduced emissions compared to conventional hydrogen production methods.