Selective Hydrogenation of Acetylene in the Presence of Ethylene on K+ -beta-Zeolite Supported Pd and PdAg Catalysts
Abstract
The selective hydrogenation of acetylene in the presence of ethylene has been studied on K+ exchanged {beta}-zeolite supported Pd and PdAg catalysts. Results from batch reactor studies with Fourier transform infrared spectroscopy (FTIR) have shown that the K+-{beta}-zeolite support is more selective than the Al2O3 or Na+-{beta}-zeolite supports toward the hydrogenation of acetylene. The rate and equilibrium constants for Pd/K+-{beta}-zeolite and PdAg/K+-{beta}-zeolite were determined using a Langmuir-Hinshelwood model. The selectivity of the PdAg bimetallic catalyst is twice of that of the Pd catalyst. Results from flow reactor studies show that the PdAg/K+-{beta}-zeolite catalyst has higher selectivity but lower activity toward acetylene hydrogenation than the Pd/K+-{beta}-zeolite catalyst. The selectivity to the undesirable ethane by-product is inhibited on the bimetallic catalyst. Extended X-ray absorption fine structure (EXAFS) studies and transmission electron microscope (TEM) analysis confirm the formation of Pd-Ag bimetallic bonds in the PdAg/K+-{beta}-zeolite catalyst.
- Authors:
- Publication Date:
- Research Org.:
- Brookhaven National Laboratory (BNL) National Synchrotron Light Source
- Sponsoring Org.:
- Doe - Office Of Science
- OSTI Identifier:
- 959635
- Report Number(s):
- BNL-82621-2009-JA
TRN: US201016%%779
- DOE Contract Number:
- DE-AC02-98CH10886
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: Applied Catalysis A: General; Journal Volume: 333
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABSORPTION; ACETYLENE; BY-PRODUCTS; CATALYSTS; ELECTRON MICROSCOPES; ETHANE; ETHYLENE; FINE STRUCTURE; HYDROGENATION; SPECTROSCOPY; ZEOLITES; national synchrotron light source
Citation Formats
Huang,W., Pyrz, W., Lobo, R., and Chen, J. Selective Hydrogenation of Acetylene in the Presence of Ethylene on K+ -beta-Zeolite Supported Pd and PdAg Catalysts. United States: N. p., 2007.
Web. doi:10.1016/j.apcata.2007.09.017.
Huang,W., Pyrz, W., Lobo, R., & Chen, J. Selective Hydrogenation of Acetylene in the Presence of Ethylene on K+ -beta-Zeolite Supported Pd and PdAg Catalysts. United States. doi:10.1016/j.apcata.2007.09.017.
Huang,W., Pyrz, W., Lobo, R., and Chen, J. Mon .
"Selective Hydrogenation of Acetylene in the Presence of Ethylene on K+ -beta-Zeolite Supported Pd and PdAg Catalysts". United States.
doi:10.1016/j.apcata.2007.09.017.
@article{osti_959635,
title = {Selective Hydrogenation of Acetylene in the Presence of Ethylene on K+ -beta-Zeolite Supported Pd and PdAg Catalysts},
author = {Huang,W. and Pyrz, W. and Lobo, R. and Chen, J.},
abstractNote = {The selective hydrogenation of acetylene in the presence of ethylene has been studied on K+ exchanged {beta}-zeolite supported Pd and PdAg catalysts. Results from batch reactor studies with Fourier transform infrared spectroscopy (FTIR) have shown that the K+-{beta}-zeolite support is more selective than the Al2O3 or Na+-{beta}-zeolite supports toward the hydrogenation of acetylene. The rate and equilibrium constants for Pd/K+-{beta}-zeolite and PdAg/K+-{beta}-zeolite were determined using a Langmuir-Hinshelwood model. The selectivity of the PdAg bimetallic catalyst is twice of that of the Pd catalyst. Results from flow reactor studies show that the PdAg/K+-{beta}-zeolite catalyst has higher selectivity but lower activity toward acetylene hydrogenation than the Pd/K+-{beta}-zeolite catalyst. The selectivity to the undesirable ethane by-product is inhibited on the bimetallic catalyst. Extended X-ray absorption fine structure (EXAFS) studies and transmission electron microscope (TEM) analysis confirm the formation of Pd-Ag bimetallic bonds in the PdAg/K+-{beta}-zeolite catalyst.},
doi = {10.1016/j.apcata.2007.09.017},
journal = {Applied Catalysis A: General},
number = ,
volume = 333,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
-
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