Low-Carbon Hydrogen Technologies: Methane Pyrolysis for Production of Low-Carbon Hydrogen and Solid Carbons

Methane pyrolysis offers a viable route for producing low-carbon hydrogen, providing an eco-friendly substitute for traditional techniques such as steam methane reforming. This method thermally breaks down methane (CH4) into hydrogen gas (H2) and solid carbon, preventing direct CO2 emissions during production. Commonly known as “turquoise hydrogen,” this approach generates a valuable solid carbon by-product, which can be captured or used in industrial processes, improving economic feasibility. The technology utilises current natural gas distribution systems, allowing for decentralised hydrogen generation while incorporating renewable energy sources to drive the high-temperature reaction. This chapter thoroughly examines methane pyrolysis, addressing essential chemical mechanisms, catalytic and non-catalytic routes, reactor configurations, and operational issues such as catalyst deactivation and carbon handling. It explores the importance of operating conditions, kinetic modelling, and new commercial initiatives by firms such as Monolith Materials and Hazer Group, showcasing scalability and market prospects. The advantages for the environment and the economy depend on aspects such as methane leaks, the carbon intensity of energy sources, and the final application of solid carbon products, including carbon black or graphite. Life cycle assessments show that methane pyrolysis, when using clean energy, can attain a carbon footprint much lower than the conventional methods. Methane pyrolysis connects fossil fuel infrastructure to a low-carbon future, positioning it as a key technology for the hydrogen economy, with continuous advancements in catalysts and reactor designs set to improve its scalability and influence.