Decoupled Activation-Selectivity Control in a Filament-Catalyst Reactor for CH4 Upgrading

Abstract Direct non-oxidative conversion of methane to ethylene and aromatics is highly attractive but fundamentally constrained by the tradeoff between conversion and selectivity under isothermal conditions. Here, we overcome this challenge using a non-isothermal filament catalyst reactor that spatially separates methane activation and selectivity tuning. A Joule-heated molybdenum filament reaches 1000–1457 °C to activate methane, while a Pd based catalyst layer coated in the reactor inner shell operates at much lower temperature (154–350 °C) to promote selective hydrocarbon transformation. This decoupling enables high methane conversion in the high-temperature zone, while facilitating controlled aromatization and hydrogenation of reactive intermediates over Pd catalyst in the low-temperature zone, achieving nearly 40% yield of ethylene and BTX, with 62% hydrogen yield. Coking occurs only on the filament surface, remaining minimal and regenerable. Techno economic and life cycle analyses indicate strong potential for economically competitive production of value-added chemicals from methane with net-zero emissions using this reactor concept.