Transient behavior and reaction mechanism of CO catalytic ignition over a CuO–CeO2 mixed oxide

Abstract This study focuses on the variation in activity-controlling factors during CO catalytic ignition over a CuO–CeO2 catalyst. The activity for combustion follows decreasing order of > CuO CeO2. Except inactive CeO2, increasing temperature induces to achieve self-sustained and CuO–CeO2. However, provides enough copper sites adsorb CO, abundant active lattice oxygen, thus obtaining higher hot zone (208.3°C) than that (197.3 °C). Catalytic triggers kinetic transition from low-rate steady-state regime high-rate regime. During induction process, Raman, X-ray photoelectron spectroscopy (XPS), temperature-programmed desorption (CO-TPD) infrared (IR) results suggested is preferentially adsorbed oxygen vacancies (Cu+-[Ov]-Ce3+) yield Cu+-[C O]-Ce3+ complexes. Because self-poisoning traces react at relative rate, which entirely governed by kinetics CO-covered surface heat transport until pre-ignition Nonetheless, complex major contributor ignition. step-response runs models testified after ignition, phase occurs an oxygen-covered surface. combustion, rapid gas diffusivity mass transfer beneficial handling low coverage CO. takes part oxidation.