Effects of nanocrystalline CeO2 supports on the properties and performance of Ni-Rh bimetallic catalyst for oxidative steam reforming of ethanol

Junichiro Kugai, Velu Subramani, Chunshan Song, Mark H. Engelhard, Ya Huei Chin

Research output: Contribution to journalArticle

203 Citations (Scopus)

Abstract

This study focuses on the effects of the CeO2 support properties on the catalyst properties and performance of bimetallic Ni-Rh/CeO2 catalysts containing 5 wt% Ni and 1 wt% Rh for the oxidative steam reforming (OSR) of ethanol for hydrogen production and fuel cell applications. Three CeO2 supports with different crystal sizes and surface areas were examined. The surface areas of these supports increases in the order of CeO2-I (74 m2/g) < CeO2-II (92 m2/g) < CeO2-III (154 m2/g), but their crystallite sizes were about 10.2, 29.3, and 6.5 nm, respectively. The properties of Ni-Rh/CeO2 catalysts were investigated by XRD, TPR, H2 chemisorption, and in situ XPS techniques. The Rh metal dispersion increased while the Ni metal dispersion decreased with decreasing crystallite sizes of CeO2. TPR studies revealed the existence of a Rh-CeO2 metal-support interaction as well as Ni-Rh interaction in the Ni-Rh bimetallic catalyst supported on CeO2-III with a crystallite size of about 6.5 nm. The in situ XPS studies corroborated the TPR results. The reduced Ni and Rh species were reversibly oxidized, suggesting the existence of Ni-Rh redox species rather than NiRh surface alloy in the present catalyst system. The Rh species became highly dispersed when the crystallite size of CeO2 support was smaller. Comparing the catalytic performance in the OSR of ethanol with the properties of the catalysts demonstrated that both ethanol conversion and H2 selectivity increased and the selectivity for undesirable byproducts decreased with increasing Rh metal dispersion. Best catalytic performance for OSR was achieved by supporting Ni-Rh bimetallic catalysts on the nanocrystalline CeO 2-III. The Ni-Rh/CeO2-III catalyst exhibited stable activity and selectivity during on-stream operations at 450 °C and as well as at 600 °C.

Original languageEnglish (US)
Pages (from-to)430-440
Number of pages11
JournalJournal of Catalysis
Volume238
Issue number2
DOIs
StatePublished - Mar 10 2006

Fingerprint

Steam reforming
steam
Ethanol
ethyl alcohol
catalysts
Catalysts
Crystallite size
Metals
Catalyst selectivity
selectivity
Catalyst supports
metals
X ray photoelectron spectroscopy
Hydrogen fuels
Chemisorption
Hydrogen production
hydrogen production
Byproducts
Fuel cells
Catalyst activity

All Science Journal Classification (ASJC) codes

  • Catalysis
  • Physical and Theoretical Chemistry

Cite this

@article{b2a8ca2efcfb42a88b0eed35f74ea4bf,
title = "Effects of nanocrystalline CeO2 supports on the properties and performance of Ni-Rh bimetallic catalyst for oxidative steam reforming of ethanol",
abstract = "This study focuses on the effects of the CeO2 support properties on the catalyst properties and performance of bimetallic Ni-Rh/CeO2 catalysts containing 5 wt{\%} Ni and 1 wt{\%} Rh for the oxidative steam reforming (OSR) of ethanol for hydrogen production and fuel cell applications. Three CeO2 supports with different crystal sizes and surface areas were examined. The surface areas of these supports increases in the order of CeO2-I (74 m2/g) < CeO2-II (92 m2/g) < CeO2-III (154 m2/g), but their crystallite sizes were about 10.2, 29.3, and 6.5 nm, respectively. The properties of Ni-Rh/CeO2 catalysts were investigated by XRD, TPR, H2 chemisorption, and in situ XPS techniques. The Rh metal dispersion increased while the Ni metal dispersion decreased with decreasing crystallite sizes of CeO2. TPR studies revealed the existence of a Rh-CeO2 metal-support interaction as well as Ni-Rh interaction in the Ni-Rh bimetallic catalyst supported on CeO2-III with a crystallite size of about 6.5 nm. The in situ XPS studies corroborated the TPR results. The reduced Ni and Rh species were reversibly oxidized, suggesting the existence of Ni-Rh redox species rather than NiRh surface alloy in the present catalyst system. The Rh species became highly dispersed when the crystallite size of CeO2 support was smaller. Comparing the catalytic performance in the OSR of ethanol with the properties of the catalysts demonstrated that both ethanol conversion and H2 selectivity increased and the selectivity for undesirable byproducts decreased with increasing Rh metal dispersion. Best catalytic performance for OSR was achieved by supporting Ni-Rh bimetallic catalysts on the nanocrystalline CeO 2-III. The Ni-Rh/CeO2-III catalyst exhibited stable activity and selectivity during on-stream operations at 450 °C and as well as at 600 °C.",
author = "Junichiro Kugai and Velu Subramani and Chunshan Song and Engelhard, {Mark H.} and Chin, {Ya Huei}",
year = "2006",
month = "3",
day = "10",
doi = "10.1016/j.jcat.2006.01.001",
language = "English (US)",
volume = "238",
pages = "430--440",
journal = "Journal of Catalysis",
issn = "0021-9517",
publisher = "Academic Press Inc.",
number = "2",

}

Effects of nanocrystalline CeO2 supports on the properties and performance of Ni-Rh bimetallic catalyst for oxidative steam reforming of ethanol. / Kugai, Junichiro; Subramani, Velu; Song, Chunshan; Engelhard, Mark H.; Chin, Ya Huei.

In: Journal of Catalysis, Vol. 238, No. 2, 10.03.2006, p. 430-440.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Effects of nanocrystalline CeO2 supports on the properties and performance of Ni-Rh bimetallic catalyst for oxidative steam reforming of ethanol

AU - Kugai, Junichiro

AU - Subramani, Velu

AU - Song, Chunshan

AU - Engelhard, Mark H.

AU - Chin, Ya Huei

PY - 2006/3/10

Y1 - 2006/3/10

N2 - This study focuses on the effects of the CeO2 support properties on the catalyst properties and performance of bimetallic Ni-Rh/CeO2 catalysts containing 5 wt% Ni and 1 wt% Rh for the oxidative steam reforming (OSR) of ethanol for hydrogen production and fuel cell applications. Three CeO2 supports with different crystal sizes and surface areas were examined. The surface areas of these supports increases in the order of CeO2-I (74 m2/g) < CeO2-II (92 m2/g) < CeO2-III (154 m2/g), but their crystallite sizes were about 10.2, 29.3, and 6.5 nm, respectively. The properties of Ni-Rh/CeO2 catalysts were investigated by XRD, TPR, H2 chemisorption, and in situ XPS techniques. The Rh metal dispersion increased while the Ni metal dispersion decreased with decreasing crystallite sizes of CeO2. TPR studies revealed the existence of a Rh-CeO2 metal-support interaction as well as Ni-Rh interaction in the Ni-Rh bimetallic catalyst supported on CeO2-III with a crystallite size of about 6.5 nm. The in situ XPS studies corroborated the TPR results. The reduced Ni and Rh species were reversibly oxidized, suggesting the existence of Ni-Rh redox species rather than NiRh surface alloy in the present catalyst system. The Rh species became highly dispersed when the crystallite size of CeO2 support was smaller. Comparing the catalytic performance in the OSR of ethanol with the properties of the catalysts demonstrated that both ethanol conversion and H2 selectivity increased and the selectivity for undesirable byproducts decreased with increasing Rh metal dispersion. Best catalytic performance for OSR was achieved by supporting Ni-Rh bimetallic catalysts on the nanocrystalline CeO 2-III. The Ni-Rh/CeO2-III catalyst exhibited stable activity and selectivity during on-stream operations at 450 °C and as well as at 600 °C.

AB - This study focuses on the effects of the CeO2 support properties on the catalyst properties and performance of bimetallic Ni-Rh/CeO2 catalysts containing 5 wt% Ni and 1 wt% Rh for the oxidative steam reforming (OSR) of ethanol for hydrogen production and fuel cell applications. Three CeO2 supports with different crystal sizes and surface areas were examined. The surface areas of these supports increases in the order of CeO2-I (74 m2/g) < CeO2-II (92 m2/g) < CeO2-III (154 m2/g), but their crystallite sizes were about 10.2, 29.3, and 6.5 nm, respectively. The properties of Ni-Rh/CeO2 catalysts were investigated by XRD, TPR, H2 chemisorption, and in situ XPS techniques. The Rh metal dispersion increased while the Ni metal dispersion decreased with decreasing crystallite sizes of CeO2. TPR studies revealed the existence of a Rh-CeO2 metal-support interaction as well as Ni-Rh interaction in the Ni-Rh bimetallic catalyst supported on CeO2-III with a crystallite size of about 6.5 nm. The in situ XPS studies corroborated the TPR results. The reduced Ni and Rh species were reversibly oxidized, suggesting the existence of Ni-Rh redox species rather than NiRh surface alloy in the present catalyst system. The Rh species became highly dispersed when the crystallite size of CeO2 support was smaller. Comparing the catalytic performance in the OSR of ethanol with the properties of the catalysts demonstrated that both ethanol conversion and H2 selectivity increased and the selectivity for undesirable byproducts decreased with increasing Rh metal dispersion. Best catalytic performance for OSR was achieved by supporting Ni-Rh bimetallic catalysts on the nanocrystalline CeO 2-III. The Ni-Rh/CeO2-III catalyst exhibited stable activity and selectivity during on-stream operations at 450 °C and as well as at 600 °C.

UR - http://www.scopus.com/inward/record.url?scp=32444447286&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=32444447286&partnerID=8YFLogxK

U2 - 10.1016/j.jcat.2006.01.001

DO - 10.1016/j.jcat.2006.01.001

M3 - Article

AN - SCOPUS:32444447286

VL - 238

SP - 430

EP - 440

JO - Journal of Catalysis

JF - Journal of Catalysis

SN - 0021-9517

IS - 2

ER -