Rare earth metal modified three dimensionally ordered macroporous MnOx-CeO2 catalyst for diesel soot combustion
来源期刊：Journal of Rare Earths2018年第1期
论文作者：Qing Tang Jun Du Bin Xie Yu Yang Wenchong Yu Changyuan Tao
文章页码：64 - 71
摘 要：Three dimensionally ordered macroporous（3 DOM） Ce-based catalysts were successfully prepared via a surfactant-assisted colloidal crystal template（CCT） route. The as-synthesized catalysts showed wellordered structures with macropores and small interconnected pore windows. The Raman results indicate that the catalyst persists pure fluorite cubic phases until the molar ratio of Mn exceeds 0.3, therefore MnOx particles form and impede the contact of the active site and the reagent and restraining soot combustion. The doping of Nd into MnOx-CeO2 enhances the catalytic activity because of increased oxygen vacancy, Mn4+content and stronger redox ability. Nd-doping also improves thermal stability of the catalyst due to less sintering and none phase separation after thermal aging. The fresh and aged Mn0.3Ce0.6Nd0.1O2 catalysts show the maximum oxidation rate for soot at 331 and 355 ℃ in the O2/N2 atmosphere, achieving a nearly 100% CO2 selectivity.
Qing Tang，Jun Du，Bin Xie，Yu Yang，Wenchong Yu，Changyuan Tao
Laboratory of Green Chemistry and Chemical,College of Chemistry and Chemical Engineering,Chongqing University
摘 要：Three dimensionally ordered macroporous（3 DOM） Ce-based catalysts were successfully prepared via a surfactant-assisted colloidal crystal template（CCT） route. The as-synthesized catalysts showed wellordered structures with macropores and small interconnected pore windows. The Raman results indicate that the catalyst persists pure fluorite cubic phases until the molar ratio of Mn exceeds 0.3, therefore MnOx particles form and impede the contact of the active site and the reagent and restraining soot combustion. The doping of Nd into MnOx-CeO2 enhances the catalytic activity because of increased oxygen vacancy, Mn4+content and stronger redox ability. Nd-doping also improves thermal stability of the catalyst due to less sintering and none phase separation after thermal aging. The fresh and aged Mn0.3Ce0.6Nd0.1O2 catalysts show the maximum oxidation rate for soot at 331 and 355 ℃ in the O2/N2 atmosphere, achieving a nearly 100% CO2 selectivity.
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