Effect of framework Al content on HY acidity and cracking activity

M. A. Kuehne, S. M. Babitz, Harold H Kung, J. T. Miller

Research output: Contribution to journalArticle

45 Citations (Scopus)

Abstract

The acidic properties and 2-methylpentane cracking turnover frequencies (TOFs) were compared for HY and two dealuminated HY zeolites with similar levels of framework Al: HDY that was dealuminated by ammonium hexafluorosilicate, and a (H,NH4)-USY zeolite that was dealuminated by steam. The acid strength distributions were determined by microcalorimetry of NH3 adsorption, and the types of acid sites by FTIR spectroscopy. All zeolites possessed Brønsted acid sites with very few Lewis acid sites. The differential heat of adsorption of NH3 on these zeolites was nearly constant: about 120 kJ/mol for HY and HDY and approximately 7 kJ/mol higher for the (H,NH4)-USY. The cracking TOF for HDY was five times larger than HY, while the TOF of (H,NH4)-USY was 80 times higher. These results suggest that the cracking activity may be affected by other factors in addition to acid strength.

Original languageEnglish
Pages (from-to)293-299
Number of pages7
JournalApplied Catalysis A: General
Volume166
Issue number2
Publication statusPublished - Jan 8 1998

Fingerprint

Zeolites
Acidity
Acids
Adsorption
Lewis Acids
Steam
Spectroscopy

Keywords

  • Cracking, effect of acidity and AI content
  • USY zeolite, acidity
  • USY zeolite, effect of AI content
  • USY zeolite, hydrocarbon cracking

ASJC Scopus subject areas

  • Catalysis
  • Process Chemistry and Technology

Cite this

Kuehne, M. A., Babitz, S. M., Kung, H. H., & Miller, J. T. (1998). Effect of framework Al content on HY acidity and cracking activity. Applied Catalysis A: General, 166(2), 293-299.

Effect of framework Al content on HY acidity and cracking activity. / Kuehne, M. A.; Babitz, S. M.; Kung, Harold H; Miller, J. T.

In: Applied Catalysis A: General, Vol. 166, No. 2, 08.01.1998, p. 293-299.

Research output: Contribution to journalArticle

Kuehne, MA, Babitz, SM, Kung, HH & Miller, JT 1998, 'Effect of framework Al content on HY acidity and cracking activity', Applied Catalysis A: General, vol. 166, no. 2, pp. 293-299.
Kuehne, M. A. ; Babitz, S. M. ; Kung, Harold H ; Miller, J. T. / Effect of framework Al content on HY acidity and cracking activity. In: Applied Catalysis A: General. 1998 ; Vol. 166, No. 2. pp. 293-299.
@article{4473b573fbe04db5823f03faedeb5780,
title = "Effect of framework Al content on HY acidity and cracking activity",
abstract = "The acidic properties and 2-methylpentane cracking turnover frequencies (TOFs) were compared for HY and two dealuminated HY zeolites with similar levels of framework Al: HDY that was dealuminated by ammonium hexafluorosilicate, and a (H,NH4)-USY zeolite that was dealuminated by steam. The acid strength distributions were determined by microcalorimetry of NH3 adsorption, and the types of acid sites by FTIR spectroscopy. All zeolites possessed Br{\o}nsted acid sites with very few Lewis acid sites. The differential heat of adsorption of NH3 on these zeolites was nearly constant: about 120 kJ/mol for HY and HDY and approximately 7 kJ/mol higher for the (H,NH4)-USY. The cracking TOF for HDY was five times larger than HY, while the TOF of (H,NH4)-USY was 80 times higher. These results suggest that the cracking activity may be affected by other factors in addition to acid strength.",
keywords = "Cracking, effect of acidity and AI content, USY zeolite, acidity, USY zeolite, effect of AI content, USY zeolite, hydrocarbon cracking",
author = "Kuehne, {M. A.} and Babitz, {S. M.} and Kung, {Harold H} and Miller, {J. T.}",
year = "1998",
month = "1",
day = "8",
language = "English",
volume = "166",
pages = "293--299",
journal = "Applied Catalysis A: General",
issn = "0926-860X",
publisher = "Elsevier",
number = "2",

}

TY - JOUR

T1 - Effect of framework Al content on HY acidity and cracking activity

AU - Kuehne, M. A.

AU - Babitz, S. M.

AU - Kung, Harold H

AU - Miller, J. T.

PY - 1998/1/8

Y1 - 1998/1/8

N2 - The acidic properties and 2-methylpentane cracking turnover frequencies (TOFs) were compared for HY and two dealuminated HY zeolites with similar levels of framework Al: HDY that was dealuminated by ammonium hexafluorosilicate, and a (H,NH4)-USY zeolite that was dealuminated by steam. The acid strength distributions were determined by microcalorimetry of NH3 adsorption, and the types of acid sites by FTIR spectroscopy. All zeolites possessed Brønsted acid sites with very few Lewis acid sites. The differential heat of adsorption of NH3 on these zeolites was nearly constant: about 120 kJ/mol for HY and HDY and approximately 7 kJ/mol higher for the (H,NH4)-USY. The cracking TOF for HDY was five times larger than HY, while the TOF of (H,NH4)-USY was 80 times higher. These results suggest that the cracking activity may be affected by other factors in addition to acid strength.

AB - The acidic properties and 2-methylpentane cracking turnover frequencies (TOFs) were compared for HY and two dealuminated HY zeolites with similar levels of framework Al: HDY that was dealuminated by ammonium hexafluorosilicate, and a (H,NH4)-USY zeolite that was dealuminated by steam. The acid strength distributions were determined by microcalorimetry of NH3 adsorption, and the types of acid sites by FTIR spectroscopy. All zeolites possessed Brønsted acid sites with very few Lewis acid sites. The differential heat of adsorption of NH3 on these zeolites was nearly constant: about 120 kJ/mol for HY and HDY and approximately 7 kJ/mol higher for the (H,NH4)-USY. The cracking TOF for HDY was five times larger than HY, while the TOF of (H,NH4)-USY was 80 times higher. These results suggest that the cracking activity may be affected by other factors in addition to acid strength.

KW - Cracking, effect of acidity and AI content

KW - USY zeolite, acidity

KW - USY zeolite, effect of AI content

KW - USY zeolite, hydrocarbon cracking

UR - http://www.scopus.com/inward/record.url?scp=0000575692&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0000575692&partnerID=8YFLogxK

M3 - Article

VL - 166

SP - 293

EP - 299

JO - Applied Catalysis A: General

JF - Applied Catalysis A: General

SN - 0926-860X

IS - 2

ER -