Micro-/mesoporous copper-containing zeolite Y applied in NH3-SCR, DeNO
نویسندگان
چکیده
Zeolite Y was prepared by a dense-gel method and subsequently modified either treatment with diethylamine (DEA), sodium hydroxide (NaOH) or disodium ethylenediaminetetraacetate (Na2H2EDTA), sequential (H4EDTA-NaOH H4EDTA-NaOH-Na2H2EDTA). Individual did not succeed in introducing mesoporosity the parent zeolite Y, while lead to formation of mesopores. After introduction Cu2+ ions, obtained materials were studied as catalysts for selective catalytic reduction NOx NH3 (NH3-SCR, DeNOx). The investigations reveal similar NO conversion all Cu-containing up 450 °C, independent introduced mesoporosity. Insights into dynamics NH3-SCR intermediates through rapid scan FT-IR show that Cu–Y, rate-determining step is mixed [Cu(O−)(NH3)n-1(NO)]2+ complexes, which initiate reaction.
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ژورنال
عنوان ژورنال: Microporous and Mesoporous Materials
سال: 2022
ISSN: ['1873-3093', '1387-1811']
DOI: https://doi.org/10.1016/j.micromeso.2022.111793