Dehydrogenation of ethylbenzene over zirconium-based perovskite-type catalysts of AZrO3 (A

Ca, Sr, Ba)

Ryo Watanabe, Yoshinori Saito, Choji Fukuhara

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

The aim of this work was to investigate the catalytic performance of the AZrO3 (A: Ca, Sr or Ba) catalysts for the dehydrogenation of ethylbenzene (EBDH) to produce styrene and to clarify an important factor for the high dehydrogenation activity. Among the AZrO3 catalysts, only the BaZrO3 (BZO) catalyst showed a significantly high activity for EBDH and the activity increased with time, while the CaZrO3 and SrZrO3 catalysts almost did not provide any activity at 823 K. Comparing the styrene yield over the BZO catalyst with that over the industrial potassium-promoted iron oxide (Fe-K) catalyst, the BZO catalyst showed a lower styrene yield than the Fe-K catalyst at the initial stage of the reaction. However, after 40 min of EBDH, the BZO catalyst exhibited a higher styrene yield than the Fe-K catalyst. Based on an ESR measurement, a sharp signal at g = 2.004, which was identified as an unpaired electron trapped in oxygen vacancies, was detected in the BZO catalyst after dehydrogenation. The number of oxygen vacancies increased with change in the dehydrogenation activity. In addition, the BZO catalyst with a pretreatment by H2 reduction presented a high activity without an induction period. Comparing the profiles of the temperature desorption of ethylbenzene (EB) over the prereduced catalyst to that of the untreated BZO catalyst, a chemisorbed species of EB was detected over the prereduced BZO catalyst, although a physisorbed species was present on the surface of the untreated catalyst. Hence, the production of oxygen vacancies opened the adsorption channel of EB and created the reactive site, which produced a high EBDH activity.

Original languageEnglish
Pages (from-to)344-351
Number of pages8
JournalApplied Catalysis A: General
Volume482
DOIs
Publication statusPublished - 2014 Jul 22
Externally publishedYes

Fingerprint

Ethylbenzene
Dehydrogenation
Zirconium
Perovskite
Catalysts
Styrene
Oxygen vacancies
perovskite
ethylbenzene
Iron oxides

Keywords

  • BaZrO3
  • Dehydrogenation of ethylbenzene
  • ESR
  • Oxygen vacancy
  • Perovskite oxide catalyst

ASJC Scopus subject areas

  • Catalysis
  • Process Chemistry and Technology

Cite this

Dehydrogenation of ethylbenzene over zirconium-based perovskite-type catalysts of AZrO3 (A : Ca, Sr, Ba). / Watanabe, Ryo; Saito, Yoshinori; Fukuhara, Choji.

In: Applied Catalysis A: General, Vol. 482, 22.07.2014, p. 344-351.

Research output: Contribution to journalArticle

@article{dcd2251a79c24f4392ed641829a3d40d,
title = "Dehydrogenation of ethylbenzene over zirconium-based perovskite-type catalysts of AZrO3 (A: Ca, Sr, Ba)",
abstract = "The aim of this work was to investigate the catalytic performance of the AZrO3 (A: Ca, Sr or Ba) catalysts for the dehydrogenation of ethylbenzene (EBDH) to produce styrene and to clarify an important factor for the high dehydrogenation activity. Among the AZrO3 catalysts, only the BaZrO3 (BZO) catalyst showed a significantly high activity for EBDH and the activity increased with time, while the CaZrO3 and SrZrO3 catalysts almost did not provide any activity at 823 K. Comparing the styrene yield over the BZO catalyst with that over the industrial potassium-promoted iron oxide (Fe-K) catalyst, the BZO catalyst showed a lower styrene yield than the Fe-K catalyst at the initial stage of the reaction. However, after 40 min of EBDH, the BZO catalyst exhibited a higher styrene yield than the Fe-K catalyst. Based on an ESR measurement, a sharp signal at g = 2.004, which was identified as an unpaired electron trapped in oxygen vacancies, was detected in the BZO catalyst after dehydrogenation. The number of oxygen vacancies increased with change in the dehydrogenation activity. In addition, the BZO catalyst with a pretreatment by H2 reduction presented a high activity without an induction period. Comparing the profiles of the temperature desorption of ethylbenzene (EB) over the prereduced catalyst to that of the untreated BZO catalyst, a chemisorbed species of EB was detected over the prereduced BZO catalyst, although a physisorbed species was present on the surface of the untreated catalyst. Hence, the production of oxygen vacancies opened the adsorption channel of EB and created the reactive site, which produced a high EBDH activity.",
keywords = "BaZrO3, Dehydrogenation of ethylbenzene, ESR, Oxygen vacancy, Perovskite oxide catalyst",
author = "Ryo Watanabe and Yoshinori Saito and Choji Fukuhara",
year = "2014",
month = "7",
day = "22",
doi = "10.1016/j.apcata.2014.06.012",
language = "English",
volume = "482",
pages = "344--351",
journal = "Applied Catalysis A: General",
issn = "0926-860X",
publisher = "Elsevier",

}

TY - JOUR

T1 - Dehydrogenation of ethylbenzene over zirconium-based perovskite-type catalysts of AZrO3 (A

T2 - Ca, Sr, Ba)

AU - Watanabe, Ryo

AU - Saito, Yoshinori

AU - Fukuhara, Choji

PY - 2014/7/22

Y1 - 2014/7/22

N2 - The aim of this work was to investigate the catalytic performance of the AZrO3 (A: Ca, Sr or Ba) catalysts for the dehydrogenation of ethylbenzene (EBDH) to produce styrene and to clarify an important factor for the high dehydrogenation activity. Among the AZrO3 catalysts, only the BaZrO3 (BZO) catalyst showed a significantly high activity for EBDH and the activity increased with time, while the CaZrO3 and SrZrO3 catalysts almost did not provide any activity at 823 K. Comparing the styrene yield over the BZO catalyst with that over the industrial potassium-promoted iron oxide (Fe-K) catalyst, the BZO catalyst showed a lower styrene yield than the Fe-K catalyst at the initial stage of the reaction. However, after 40 min of EBDH, the BZO catalyst exhibited a higher styrene yield than the Fe-K catalyst. Based on an ESR measurement, a sharp signal at g = 2.004, which was identified as an unpaired electron trapped in oxygen vacancies, was detected in the BZO catalyst after dehydrogenation. The number of oxygen vacancies increased with change in the dehydrogenation activity. In addition, the BZO catalyst with a pretreatment by H2 reduction presented a high activity without an induction period. Comparing the profiles of the temperature desorption of ethylbenzene (EB) over the prereduced catalyst to that of the untreated BZO catalyst, a chemisorbed species of EB was detected over the prereduced BZO catalyst, although a physisorbed species was present on the surface of the untreated catalyst. Hence, the production of oxygen vacancies opened the adsorption channel of EB and created the reactive site, which produced a high EBDH activity.

AB - The aim of this work was to investigate the catalytic performance of the AZrO3 (A: Ca, Sr or Ba) catalysts for the dehydrogenation of ethylbenzene (EBDH) to produce styrene and to clarify an important factor for the high dehydrogenation activity. Among the AZrO3 catalysts, only the BaZrO3 (BZO) catalyst showed a significantly high activity for EBDH and the activity increased with time, while the CaZrO3 and SrZrO3 catalysts almost did not provide any activity at 823 K. Comparing the styrene yield over the BZO catalyst with that over the industrial potassium-promoted iron oxide (Fe-K) catalyst, the BZO catalyst showed a lower styrene yield than the Fe-K catalyst at the initial stage of the reaction. However, after 40 min of EBDH, the BZO catalyst exhibited a higher styrene yield than the Fe-K catalyst. Based on an ESR measurement, a sharp signal at g = 2.004, which was identified as an unpaired electron trapped in oxygen vacancies, was detected in the BZO catalyst after dehydrogenation. The number of oxygen vacancies increased with change in the dehydrogenation activity. In addition, the BZO catalyst with a pretreatment by H2 reduction presented a high activity without an induction period. Comparing the profiles of the temperature desorption of ethylbenzene (EB) over the prereduced catalyst to that of the untreated BZO catalyst, a chemisorbed species of EB was detected over the prereduced BZO catalyst, although a physisorbed species was present on the surface of the untreated catalyst. Hence, the production of oxygen vacancies opened the adsorption channel of EB and created the reactive site, which produced a high EBDH activity.

KW - BaZrO3

KW - Dehydrogenation of ethylbenzene

KW - ESR

KW - Oxygen vacancy

KW - Perovskite oxide catalyst

UR - http://www.scopus.com/inward/record.url?scp=84903833166&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84903833166&partnerID=8YFLogxK

U2 - 10.1016/j.apcata.2014.06.012

DO - 10.1016/j.apcata.2014.06.012

M3 - Article

VL - 482

SP - 344

EP - 351

JO - Applied Catalysis A: General

JF - Applied Catalysis A: General

SN - 0926-860X

ER -