Effects of catalysts on water decomposition and hydrogen oxidation reactions in oxygen transport membrane reactors

Oxygen transport membrane reactors (OTMRs) are used for hydrogen separation through coupling water decomposition reaction (WDR) with hydrogen oxidation reaction (HOR). The activities of catalysts towards WDR and HOR play key roles in the hydrogen separation performance. It is of great practical significance to find suitable catalysts possessing high catalytic activities for WDR and HOR, respectively. In this work, M/SDC (M = Ru, Pd and Pt) catalysts were prepared and their catalytic activities towards WDR and HOR were evaluated systematically and separately on OTMR for hydrogen separation. It is demonstrated that Ru/SDC catalyst shows the highest activities towards both WDR and HOR, while the activity difference among the three noble metal catalysts is small. After testing for tens of hours at temperatures up to 940 degrees C, Ru nanoparticles in Ru/SDC catalyst still remain <20 nm. The formation of solid solution and strong metal-support interaction (SMSI) between Ru and SDC support keep Ru nanoparticles in small size in the long-time test.

Automated summary

This study investigated M/SDC catalysts for hydrogen separation through WDR and HOR reactions on OTMR, demonstrating that Ru/SDC catalyst exhibits the highest activities with nanoparticles remaining <20 nm. Solid solution formation and strong metal-support interaction maintain the small size of Ru nanoparticles during long-term testing.