Characterization and removal of extra lattice species in faujasites

Michael Stockenhuber; J. A. Lercher

doi:10.1016/0927-6513(94)00056-2

Characterization and removal of extra lattice species in faujasites

Michael Stockenhuber, J. A. Lercher

Research output: Contribution to journal › Article › peer-review

35 Scopus citations

Abstract

The acidic properties of dealuminated Y-type zeolites were characterized by infrared (IR) spectroscopy, microcalorimetry, ²⁹Si magic-angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy and temperature-programmed desorption (TPD). Microcalorimetric measurements exhibited a uniform heat of adsorption (140 kJ/mol) of ammonia on the strong Brönsted acid sites. The differences in the acid site concentrations measured by adsorption of ammonia from the gas phase and by decomposition of ammonium-exchanged zeolites are discussed. The results indicate that parts of the extra lattice material consisting of cationic aluminium oxide species or silica alumina species are removed by ion exchange with aqueous solutions of ammonium hydroxide. Based on this, a method for the controlled removal of extra lattice material was developed.

Original language	English
Pages (from-to)	457-465
Number of pages	9
Journal	Microporous Materials
Volume	3
Issue number	4-5
DOIs	https://doi.org/10.1016/0927-6513(94)00056-2
State	Published - Jan 1995
Externally published	Yes

Keywords

Characterization
Extra lattice species
Faujasites
Infrared spectroscopy
Microcalorimetry

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10.1016/0927-6513(94)00056-2

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@article{b23677a68c764aa4ae224264fd125ec5,

title = "Characterization and removal of extra lattice species in faujasites",

abstract = "The acidic properties of dealuminated Y-type zeolites were characterized by infrared (IR) spectroscopy, microcalorimetry, 29Si magic-angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy and temperature-programmed desorption (TPD). Microcalorimetric measurements exhibited a uniform heat of adsorption (140 kJ/mol) of ammonia on the strong Br{\"o}nsted acid sites. The differences in the acid site concentrations measured by adsorption of ammonia from the gas phase and by decomposition of ammonium-exchanged zeolites are discussed. The results indicate that parts of the extra lattice material consisting of cationic aluminium oxide species or silica alumina species are removed by ion exchange with aqueous solutions of ammonium hydroxide. Based on this, a method for the controlled removal of extra lattice material was developed.",

keywords = "Characterization, Extra lattice species, Faujasites, Infrared spectroscopy, Microcalorimetry",

author = "Michael Stockenhuber and Lercher, {J. A.}",

note = "Funding Information: We gratefully thank Mr. Neil Hayes, Prof. Richard Joyner and the SERC Solid State NMR Facility at UMIST for the measurement of the 29Si MAS NMR spectra, Dr. H. Wernisch for the measurements of the EDAX spectra and the Christian Doppler Laboratory for financial support.",

year = "1995",

month = jan,

doi = "10.1016/0927-6513(94)00056-2",

language = "English",

volume = "3",

pages = "457--465",

journal = "Microporous Materials",

issn = "0927-6513",

publisher = "Elsevier BV",

number = "4-5",

}

TY - JOUR

T1 - Characterization and removal of extra lattice species in faujasites

AU - Stockenhuber, Michael

AU - Lercher, J. A.

N1 - Funding Information: We gratefully thank Mr. Neil Hayes, Prof. Richard Joyner and the SERC Solid State NMR Facility at UMIST for the measurement of the 29Si MAS NMR spectra, Dr. H. Wernisch for the measurements of the EDAX spectra and the Christian Doppler Laboratory for financial support.

PY - 1995/1

Y1 - 1995/1

N2 - The acidic properties of dealuminated Y-type zeolites were characterized by infrared (IR) spectroscopy, microcalorimetry, 29Si magic-angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy and temperature-programmed desorption (TPD). Microcalorimetric measurements exhibited a uniform heat of adsorption (140 kJ/mol) of ammonia on the strong Brönsted acid sites. The differences in the acid site concentrations measured by adsorption of ammonia from the gas phase and by decomposition of ammonium-exchanged zeolites are discussed. The results indicate that parts of the extra lattice material consisting of cationic aluminium oxide species or silica alumina species are removed by ion exchange with aqueous solutions of ammonium hydroxide. Based on this, a method for the controlled removal of extra lattice material was developed.

AB - The acidic properties of dealuminated Y-type zeolites were characterized by infrared (IR) spectroscopy, microcalorimetry, 29Si magic-angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy and temperature-programmed desorption (TPD). Microcalorimetric measurements exhibited a uniform heat of adsorption (140 kJ/mol) of ammonia on the strong Brönsted acid sites. The differences in the acid site concentrations measured by adsorption of ammonia from the gas phase and by decomposition of ammonium-exchanged zeolites are discussed. The results indicate that parts of the extra lattice material consisting of cationic aluminium oxide species or silica alumina species are removed by ion exchange with aqueous solutions of ammonium hydroxide. Based on this, a method for the controlled removal of extra lattice material was developed.

KW - Characterization

KW - Extra lattice species

KW - Faujasites

KW - Infrared spectroscopy

KW - Microcalorimetry

UR - http://www.scopus.com/inward/record.url?scp=0001539253&partnerID=8YFLogxK

U2 - 10.1016/0927-6513(94)00056-2

DO - 10.1016/0927-6513(94)00056-2

M3 - Article

AN - SCOPUS:0001539253

SN - 0927-6513

VL - 3

SP - 457

EP - 465

JO - Microporous Materials

JF - Microporous Materials

IS - 4-5

ER -

Characterization and removal of extra lattice species in faujasites

Abstract

Keywords

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