Preparation of hierarchical SSZ-13 by NH4F etching
نویسندگان
چکیده
NH4-SSZ-13 is etched with an aqueous solution of 40 w/% NH4F under different time/temperature conditions to obtain hierarchical derivatives. The zeolites are characterized by XRD, SEM, N2 physisorption, 29Si/27Al/19F MAS NMR, ICP-AES, and their acidity monitored in situ FTIR spectroscopy using acetonitrile as a probe molecule. results highlight that the zeolite very sensitive high temperature liquid-solid ratio treatments leading substantial crystallinity losses. These two parameters need careful tuning derivatives retaining important characteristics micropore volume framework Si/Al ratio. catalytic activity modified SSZ-13 evaluated n-propanol conversion.
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ژورنال
عنوان ژورنال: Microporous and Mesoporous Materials
سال: 2021
ISSN: ['1873-3093', '1387-1811']
DOI: https://doi.org/10.1016/j.micromeso.2020.110863