کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
40801 45866 2012 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Investigations of surface VOx species and their contributions to activities of VOx/Ti0.5Sn0.5O2 catalysts toward selective catalytic reduction of NO by NH3
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Investigations of surface VOx species and their contributions to activities of VOx/Ti0.5Sn0.5O2 catalysts toward selective catalytic reduction of NO by NH3
چکیده انگلیسی

High surface area Ti0.5Sn0.5O2 mixed oxide with rutile phase was prepared by a coprecipitation method. The surface area of Ti0.5Sn0.5O2 sample is 76.7 m2 g−1, and VOx/Ti0.5Sn0.5O2 catalysts were prepared using the mixed oxide as support. Characterizations using XRD, FT-IR, LRS, EPR, UV–vis, and TEM demonstrated that vanadium oxide species are highly dispersed on the surface of Ti0.5Sn0.5O2 support when the loading amount of vanadium oxide is ≤1.5 mmol V/100 m2 Ti0.5Sn0.5O2. The dispersed vanadium oxide species form epitaxial-growth layer on the support. In situ FT-IR (NH3 adsorption), combined with NH3-TPD, indicate that the catalyst with vanadium loading amount of 1.5 mmol V/100 m2 Ti0.5Sn0.5O2, which equals to the dispersion capability, possesses a maximum amount of Brønsted acid sites. The 1.5V/Ti0.5Sn0.5O2 catalyst exhibits the best catalytic performance and good resistance to water vapor poison for the “NO + NH3 + O2” reaction, indicating that surface dispersed polymeric vanadium oxide species are the primary active species. A possible reaction mechanism is proposed on the basis of in situ FT-IR results.

Figure optionsDownload high-quality image (183 K)Download as PowerPoint slideHighlights
► Vanadium oxide species are highly dispersed and form epitaxial-growth layer on TS support.
► The catalyst with the 1.5 mmol V/100 m2 possesses a maximum amount of Brønsted acid sites.
► Polymeric vanadium oxide species are the primary active species.
► 1.5V/TS catalyst exhibits the best catalytic performance for the “NO + NH3 + O2” reaction.
► A possible reaction mechanism is proposed on the basis of in situ FT-IR interrogation.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Catalysis A: General - Volumes 431–432, 26 July 2012, Pages 126–136
نویسندگان
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