Complete and continuous methane pyrolysis to produce carbon construction materials and hydrogen

Abstract

Apart from being considered for prospective energy applications, hydrogen (H₂) today plays a pivotal role in growing food for the global population, serving as a key ingredient for ammonia-based fertilizers. However, unabated steam methane reforming (SMR)—the predominant method of H₂ production—produces CO₂, accounting for 2–3% of global CO₂ emissions. While clean alternative approaches such as water electrolysis have struggled to compete with the cost of SMR, various embodiments of methane pyrolysis (MP) hold promise. The key problems with MP, however, have been (1) realizing complete conversion or high yield; (2) navigating the engineering challenge of removing the solid carbon byproduct, enabling continuous operation without clogging; and (3) creating a valuable carbon product, providing the complementary value allowing the H₂ price to compete with SMR. Here, we report for the first time a prototype system that addresses each of these challenges, paving the way to make a useful carbon product and H₂.