Catalytic selective ethane dehydrogenation at low-temperature with low coke formation

Abstract

Catalytic ethane dehydrogenation (EDH) was investigated to improve the efficient production of ethylene, an extremely important chemical feedstock. The perovskite oxide YCrO₃ was found to be more suitable than earlier reported catalysts because it exhibits greater activity and C₂H₄ selectivity (94.3%) in the presence of steam at 973 K. This catalyst shows the highest activity than ever under kinetic conditions, and shows very high ethane conversion under integral reaction conditions. Comparison with EDH performance under conditions without steam revealed that steam plays an important role in stabilizing the high activity. Raman spectra of spent catalysts indicated that steam prevents coke formation, which is responsible for deactivating YCrO₃. Transmission IR and XPS measurements also revealed a mechanism by which H₂O forms surface oxygen species on YCrO₃, consequently removing C₂H₆-derived coke precursors rapidly and inhibiting coke accumulation.