Exceptional performance of water splitting coupled with methane partial oxidation by oxygen-permeable membrane reactor

An oxygen-permeable membrane reactor, capable of high-performance water splitting and simultaneous methane conversion while maintaining the syngas ratio (H-2/CO) close to 2, is reported in this study. Most coupling studies of water splitting and partial oxidation of methane (POM) using oxygen-conducting ceramic membranes have so far focused on the application in high-temperature (>900 degrees C) conditions that can accelerate the kinetics of surface exchange reactions. Considerable hydrogen production through the coupling reaction is possible below 800 degrees C by adopting Ruddlesden-Popper oxide for water reduction and a Ni/perovskite/fluorite composite for POM. The membrane composition was optimized to maximize the oxygen ionic conductivity and ensure the stability. Using a chemically stable dual-phase membrane with highly active coating layers, the production of 4.5 mL center dot cm(-2)center dot min(-1) of hydrogen from water splitting and 14 mL center dot cm(-2)center dot mi(-1) of syngas from methane were stably secured at 800 degrees C. In addition, coupling reaction was confirmed to be possible even at 700 degrees C.

Automated summary

In this study, an oxygen-permeable membrane reactor capable of high-performance water splitting and simultaneous methane conversion was reported. The study showed that coupling water splitting and partial oxidation of methane is possible even below 800 degrees C using Ruddlesden-Popper oxide and a Ni/perovskite/fluorite composite. The optimized membrane composition ensured high ionic conductivity and stability, leading to stable hydrogen and syngas production.