کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
56043 47070 2011 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Improvement of catalyst stability during methane dehydroaromatization (MDA) on Mo/HZSM-5 comprising intracrystalline mesopores
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Improvement of catalyst stability during methane dehydroaromatization (MDA) on Mo/HZSM-5 comprising intracrystalline mesopores
چکیده انگلیسی

A new Mo/HZSM-5 catalyst (3 wt% Mo, Si/Al = 26) comprising a carbon-templated zeolite having intracrystalline mesopores sizing ca. 10–20 nm (HZSM-5-BP) has been prepared. For comparison purposes, an equivalent catalyst has also been prepared from a commercial zeolite (HZSM-5-ref). The materials have been extensively characterized by XRD, ICP-OES, N2 physisorption, SEM-TEM, 27Al MAS NMR, FTIR-pyridine, NH3-TPD, H2-TPR, TG-DTG analyses and TPO, and their catalytic activity evaluated for methane dehydroaromatization (MDA) at 700 °C, 1 bar, and 1500 ml/gcat h. The hierarchical Mo/HZSM-5-BP catalyst displayed a lower deactivation rate during MDA than the reference one, leading to a higher and stable aromatics yield at T.O.S. above 3 h, despite a higher amount of less reactive coke (associated to the zeolite acid sites) was produced in the former. We hypothesize that the enhanced tolerance to carbon deposits of the carbon-templated zeolite could be related to the intracrystalline mesopores acting as a trap for coke molecules and leaving a higher fraction of acid sites within the channels active for aromatization.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Catalysis Today - Volume 169, Issue 1, 1 July 2011, Pages 75–84
نویسندگان
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