کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
45072 46395 2014 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Chemical deactivation of Cu-SSZ-13 ammonia selective catalytic reduction (NH3-SCR) systems
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Chemical deactivation of Cu-SSZ-13 ammonia selective catalytic reduction (NH3-SCR) systems
چکیده انگلیسی


• Pt, Ca, Zn and P have different effects on the catalytic performance of Cu-SSZ-13.
• Deactivation by Pt affects N2 selectivity due to the high oxidation activity of Pt.
• Deactivation by Zn and Ca affects NOx conversion but with no effect on selectivity.
• Deactivation by Zn and Ca lead to pore blocking/filling, along with Cu clustering.
• P completely suppresses the activity due to a combination of several mechanisms.

The chemical deactivation of Cu-SSZ-13 Ammonia Selective Catalytic Reduction (NH3-SCR) catalysts by Pt, Zn, Ca and P has been systematically investigated using a range of analytical techniques in order to study the influence on both the zeolitic framework and the active Cu2+ ions. The results obtained demonstrate a crucial impact of P, completely suppressing the catalytic activity as a result of different deactivation mechanisms (i.e. site blocking, disruption of the zeolite framework, CuO formation and else reduction in the number of isolated Cu2+ ions). A less pronounced drop in activity is found with Ca and Zn introduction, without an appreciable adverse effect on N2 selectivity, since the catalytic deactivation is mainly brought about through a pore blocking/filling mechanism. Additionally, a drop in the amount of Cu2+ ions with the formation of CuO species also takes place, observed to be most important for the Zn-deactivated materials. Deactivation by Pt strongly affects N2 selectivity, but without a significant influence on the active sites or the zeolitic structure, basically due to the high oxidation activity of the Pt species, which highly promote N2O and NO2 formation.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Catalysis B: Environmental - Volumes 154–155, July–August 2014, Pages 339–349
نویسندگان
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