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Author Bejoy, Thomas ♦ Sugunan, S.
Source CUSAT-Thesis
Content type Text
Publisher ELSEVIER
File Format PDF
Language English
Subject Domain (in DDC) Natural sciences & mathematics ♦ Chemistry & allied sciences ♦ Technology
Subject Keyword Rare earth exchanged faujasite–Y zeolite ♦ Magic angle spinning NMR ♦ Hirschler–Plank mechanism ♦ Migration behavior ♦ Linear alkylation benzene ♦ 2-Phenyloctane ♦ Deactivation studies
Abstract The effect of residual cations in rare earth metal modified faujasite–Y zeolite has been monitored using magic angle spinning NMR spectral analysis and catalytic activity studies. The second metal ions being used are Na+, K+ and Mg+. From a comparison of the spectra of different samples, it is concluded that potassium and magnesium exchange causes a greater downfield shift in the 29Si NMR peaks. Also, lanthanum exchanged samples show migration behavior from large cages to small cages, which causes the redistribution of second counter cations. It is also observed that Mg2+ causes the most effective migration of lanthanum ions due to its greater charge. The prepared systems were effectively employed for the alkylation of benzene with 1-octene in the vapor phase. From the deactivation studies it is observed that the as-exchanged zeolites possess better stability towards reaction condition over the pure HFAU zeolite.
ISSN 13871811
Education Level UG and PG
Learning Resource Type Article