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

doi:10.1016/J.PROCI.2020.06.186

CORC > 力学研究所 > 中国科学院力学研究所 > 高温气体动力学国家重点实验室

	Transient behavior and reaction mechanism of CO catalytic ignition over a CuO–CeO2 mixed oxide
	康润宁;Ma PD; He JY; Li HX(李慧鑫); Bin F(宾峰); Wei XL(魏小林); Dou BJ; Kwun NH; Kwan SH
刊名	Proceedings of the Combustion Institute
	2020
卷号	38
DOI	10.1016/J.PROCI.2020.06.186
英文摘要	This study focuses on the variation in activity-controlling factors during CO catalytic ignition over a CuO–CeO2 catalyst. The activity for CO combustion follows the decreasing order of CuO–CeO2 > CuO > CeO2. Except for inactive CeO2, increasing temperature induces CO ignition to achieve self-sustained combustion over CuO and CuO–CeO2. However, CuO provides enough copper sites to adsorb CO, and abundant active lattice oxygen, thus obtaining a higher hot zone temperature (208.3°C) than that of CuO–CeO2 (197.3 °C). Catalytic ignition triggers a kinetic transition from the low-rate steady-state regime to a high-rate steady-state regime. During the induction process, Raman, X-ray photoelectron spectroscopy (XPS), CO temperature-programmed desorption (CO-TPD) and infrared (IR) spectroscopy results suggested that CO is preferentially adsorbed on oxygen vacancies (Cu+-[Ov]-Ce3+) to yield Cu+-[CO]-Ce3+ complexes. Because of the self-poisoning of CO, the adsorbed CO and traces of adsorbed oxygen react at a relative rate, which is entirely governed by the kinetics on the CO-covered surface and the heat transport until the pre-ignition regime. Nonetheless, the Cu+-[CO]-Ce3+ complex is a major contributor to CO ignition. The step-response runs and kinetic models testified that after ignition, a kinetic phase transition occurs from a CO-covered surface to an active lattice oxygen-covered surface. During CO self-sustained combustion, the rapid gas diffusivity and mass transfer is beneficial for handling the low coverage of CO. The active lattice oxygen of CuO takes part in CO oxidation.
分类号	一类
语种	英语
其他责任者	Feng Bin(宾峰)
内容类型	期刊论文
源URL	[http://dspace.imech.ac.cn/handle/311007/85698]
专题	力学研究所_高温气体动力学国家重点实验室
推荐引用方式 GB/T 7714	康润宁；Ma PD,He JY,Li HX,et al. Transient behavior and reaction mechanism of CO catalytic ignition over a CuO–CeO2 mixed oxide[J]. Proceedings of the Combustion Institute,2020,38.
APA	康润宁；Ma PD.,He JY.,李慧鑫.,宾峰.,魏小林.,...&Kwan SH.(2020).Transient behavior and reaction mechanism of CO catalytic ignition over a CuO–CeO2 mixed oxide.Proceedings of the Combustion Institute,38.
MLA	康润宁；Ma PD,et al."Transient behavior and reaction mechanism of CO catalytic ignition over a CuO–CeO2 mixed oxide".Proceedings of the Combustion Institute 38(2020).