Characterization of acidity in ZSM-5 zeolites: An x-ray photoelectron and IR spectroscopy study

Journal Article · Thu Jul 26 00:00:00 EDT 1990 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100378a068· OSTI ID:6331623

Borade, R; Sayari, A; Adnot, A; Kaliaguine, S ^[1]

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1. Universite Laval, Ste-Foy, Quebec (Canada)

An x-ray photoelectron spectroscopic (XPS) method is proposed for the identification and quantitation of Broensted and Lewis acid sites in ZSM-5 zeolites. The method consists of deconvoluting the N{sub 1s}XPS level of chemisorbed pyridine and measuring the relative intensities of the peak components. It was found that pyridine is chemisorbed in three different states on ZSM-5 zeolites corresponding to N{sub 1s} binding energy of 398.7, 400.0, and 401.8 eV, respectively. The first peak at 398.7 eV was assigned to N{sub 1s} level of pyridine adsorbed on Lewis sites, while the second and third were assigned to N{sub 1s} levels of pyridine adsorbed on relatively weak and strong Broensted acid sites, respectively. Comparison of the concentrations of the various acid sites as determined from the relative intensities of the N{sub 1s} components with IR spectroscopic data showed that XPS has potential applications in the identification and the quantitative determination of Broensted and Lewis acid sites in zeolites.

• OSTI ID: 6331623
• Journal Information: Journal of Physical Chemistry; (USA), Vol. 94:15; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ZEOLITES
PHOTOELECTRON SPECTROSCOPY
DATA ANALYSIS
EXPERIMENTAL DATA
INFRARED SPECTRA
LEWIS ACIDS
MEASURING INSTRUMENTS
MEASURING METHODS
DATA
ELECTRON SPECTROSCOPY
HYDROGEN COMPOUNDS
INFORMATION
INORGANIC ACIDS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
MATERIALS
MINERALS
NUMERICAL DATA
SPECTRA
SPECTROSCOPY
400201* - Chemical & Physicochemical Properties