Enhanced catalytic oxidation of diluted ethylene oxide on Pt/CeO2 catalyst under low temperature

A thorough catalytic combustion toward diluted ethylene oxide (EO) is demonstrated. The Pt active phase and CeO 2 support were selected to introduce a synergistic effect. As a result, a superior catalytic activity and less severe coking trend were observed on the Pt/CeO 2 catalyst when compared with another widely-used Pt/Al 2 O 3 catalyst. The XPS spectra and H 2 -TPR profiles evidenced that the Pt/CeO 2 catalyst has both stronger metal-support interaction and more abundant oxygen vacancies, which is believed at the heart of its excellent performance. Finally, the degradation pathways of EO were explored by in-situ DRIFTS. The weak H 2 O affinity of Pt/CeO 2 catalyst can inhibit the polycondensation reaction and result in the favorable degradation of EO. In contrast, abundant hydroxyl species were present on the hydrophilic Pt/Al 2 O 3 catalyst surface, which may serve as acid sites and complicate the EO degradation, and therefore various side products and carbon deposits would appear in this case. • Extremely diluted EO is fully oxidized on Pt/CeO 2 catalyst under low temperature • Metal-support interaction & oxygen vacancy abundance are proved the key to activity • Pt/CeO 2 shows both superior catalytic activity and anti-coking property to Pt/Al 2 O 3 • The different degradation pathways of two catalysts are elucidated by in situ DRIFTs