کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
67455 48483 2009 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Dehydration of epiandrosterone over zeolites with different pore structures and acidities
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Dehydration of epiandrosterone over zeolites with different pore structures and acidities
چکیده انگلیسی

Four kinds of large port zeolites BEA, FAU, LTL and MOR, were used as catalysts in the dehydration of a large molecule, epiandrosterone, to elucidate the effect of their pore structure on its conversion and the selectivity for 5α-androst-2-en-17-one (Δ2-olefin). Silane masking of the zeolite acid sites, measurement of their epiandrosterone uptake, and theoretical calculations to find the energy-minimized conformation in zeolite pores revealed the roles of pore structure and acid sites in the dehydration. LTL and MOR zeolites showed poor conversion and low selectivity for Δ2-olefin because of the close packing in their linear pores. BEA and FAU zeolites with three-dimensionally connected pores exhibited high conversion. Since the supercages of FAU zeolite provided enough space to allow tilted conformation of epiandrosterone with high preference for the formation of Δ2-olefin, FAU zeolites with a sufficient number of acid sites demonstrated both high conversion and selectivity in the dehydration of epiandrosterone.

FAU zeolite with a sufficient number of acid sites showed both high conversion and selectivity for Δ2-olefin in the dehydration of epiandrosterone because its supercages provided enough space to form adsorbed species with tilted conformation.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Catalysis A: Chemical - Volume 308, Issues 1–2, 4 August 2009, Pages 134–141
نویسندگان
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