Integrated electrified reactor system for efficient CO2-to-syngas conversion via e-methanation and e-POM

Abstract

This study presents the development of an electrically driven dual-stage reactor system for efficient syngas production via integrated CO₂ methanation and methane partial oxidation. A spiral-shaped metallic catalyst structure enables localized Joule heating by direct current, allowing rapid and energy-efficient temperature control. In the first stage, the Ru/CeO₂ catalyst achieved a high CO₂ conversion of 78% and CH₄ selectivity exceeding approximately 100% under low input power (10 W). In the second stage, the Ni/CeO₂ catalyst facilitated CH₄ partial oxidation with 91% CH₄ conversion and syngas production exhibiting an H₂/CO ratio of approximately 2.8. By shortening the catalyst length and increasing flow rates, the system further enhanced heat utilization and CO yield. Notably, while the standalone partial oxidation system suffered from carbon deposition, the integrated configuration demonstrated improved stability due to the presence of residual hydrogen and water from the methanation stage, which effectively suppressed coke formation. To our knowledge, this work is the first to experimentally demonstrate a fully electrified, tandem CO₂-to-syngas process combining e-methanation and e-POM in a compact system, offering a promising platform for renewable-energy-compatible chemical conversion.