Selective removal of CO from hydrocarbon-rich industrial off-gases over CeO2-supported metal oxides

Abstract

For the selective removal of CO in the off-gas streams from real-life chemical processes, the interfacial interaction between the support and the active metal oxides and the role of active oxygen species are two fascinating problems. Herein, a series of CeO2-supported metal oxide catalysts were synthesized by co-precipitation method and employed for the selective removal of CO from the off-gas stream of propane oxidation process. CuO/CeO2 catalyst exhibits full CO conversion and 100% selectivity for CO removal in off-gas stream within a rather wide temperature window of 140–190 °C, being relatively stable in 200-h long-term time-on-stream experiment. Raman spectra, H2-TPR, CO-TPD and XPS spectra studies revealed that the redox properties and the concentration of active oxygen species varied with supported metal oxide compositions, for which CuO/CeO2 catalyst exhibited the highest surface oxygen vacancy concentration, good low-temperature reduction behavior and the highest adsorption capacity of CO, thus resulting in advanced CO removal performance. This study presents a strategy to design a promising CeO2-supported catalyst for oxidation removal of CO from off-gas of alkane oxidation process.