Dehydroaromatization of methane over Sn-Pt modified Mo/H-ZSM-5 zeolite catalysts: Effect of preparation method

Themba E. Tshabalala; Neil J. Coville; James A. Anderson; Michael S. Scurrell

doi:10.1016/j.apcata.2015.06.035

Dehydroaromatization of methane over Sn-Pt modified Mo/H-ZSM-5 zeolite catalysts: Effect of preparation method

Themba E. Tshabalala, Neil J. Coville, James A. Anderson, Michael S. Scurrell^*

^*Corresponding author for this work

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

20 Citations (Scopus)

Abstract

The effect of different catalyst preparation methods to make tin-platinum modified Mo/H-ZSM-5 zeolite catalysts for methane dehydroaromatization at 700 °C was investigated. The catalysts were prepared by both incipient wetness co-impregnation and sequential impregnation and calcined at 500 °C for 6 h. Catalysts prepared by the co-impregnation method showed a good platinum dispersion (10.8%), higher than found for the Pt/Sn and Sn/Pt sequentially impregnated catalysts (5.6% and 1.4%, respectively). Successive calcination treatments influenced the location of both tin and platinum in the catalyst and a decrease in platinum dispersion after reduction was evident from CO chemisorption studies. The order of sequentially loading platinum before or after tin had an effect on the electronic and structural properties of platinum as shown by XPS and FTIR studies. Different catalytic activities and aromatic selectivities were observed for the Pt/Sn and Sn/Pt catalysts. The co-impregnated Sn-Pt and the sequentially impregnated Pt/Sn catalysts showed high aromatic selectivity (>70%) and low coke selectivity (<20%). The decrease in coke selectivity is mainly dependent on the availability of platinum sites for hydrogenation of carbonaceous species.

Original language	English
Pages (from-to)	218-226
Number of pages	9
Journal	Applied Catalysis A: General
Volume	503
Early online date	3 Jul 2015
DOIs	https://doi.org/10.1016/j.apcata.2015.06.035
Publication status	Published - 25 Aug 2015

Bibliographical note

Acknowledgements
We wish to thank the National Research Foundation (NRF) South Africa, University of Aberdeen (Scotland, UK) and University of the Witwatersrand for financial support.

Keywords

H-ZSM-5
Methane dehydroaromatization
Molybdenum
Platinum
Tin

Access to Document

10.1016/j.apcata.2015.06.035Licence: Unspecified

Cite this

@article{ed966d3926a643dc865fe26a1c710c38,

title = "Dehydroaromatization of methane over Sn-Pt modified Mo/H-ZSM-5 zeolite catalysts: Effect of preparation method",

abstract = "The effect of different catalyst preparation methods to make tin-platinum modified Mo/H-ZSM-5 zeolite catalysts for methane dehydroaromatization at 700 °C was investigated. The catalysts were prepared by both incipient wetness co-impregnation and sequential impregnation and calcined at 500 °C for 6 h. Catalysts prepared by the co-impregnation method showed a good platinum dispersion (10.8%), higher than found for the Pt/Sn and Sn/Pt sequentially impregnated catalysts (5.6% and 1.4%, respectively). Successive calcination treatments influenced the location of both tin and platinum in the catalyst and a decrease in platinum dispersion after reduction was evident from CO chemisorption studies. The order of sequentially loading platinum before or after tin had an effect on the electronic and structural properties of platinum as shown by XPS and FTIR studies. Different catalytic activities and aromatic selectivities were observed for the Pt/Sn and Sn/Pt catalysts. The co-impregnated Sn-Pt and the sequentially impregnated Pt/Sn catalysts showed high aromatic selectivity (>70%) and low coke selectivity (<20%). The decrease in coke selectivity is mainly dependent on the availability of platinum sites for hydrogenation of carbonaceous species.",

keywords = "H-ZSM-5, Methane dehydroaromatization, Molybdenum, Platinum, Tin",

author = "Tshabalala, {Themba E.} and Coville, {Neil J.} and Anderson, {James A.} and Scurrell, {Michael S.}",

note = "Acknowledgements We wish to thank the National Research Foundation (NRF) South Africa, University of Aberdeen (Scotland, UK) and University of the Witwatersrand for financial support.",

year = "2015",

month = aug,

day = "25",

doi = "10.1016/j.apcata.2015.06.035",

language = "English",

volume = "503",

pages = "218--226",

journal = "Applied Catalysis A: General",

issn = "0926-860X",

publisher = "Elsevier",

}

TY - JOUR

T1 - Dehydroaromatization of methane over Sn-Pt modified Mo/H-ZSM-5 zeolite catalysts

T2 - Effect of preparation method

AU - Tshabalala, Themba E.

AU - Coville, Neil J.

AU - Anderson, James A.

AU - Scurrell, Michael S.

N1 - Acknowledgements We wish to thank the National Research Foundation (NRF) South Africa, University of Aberdeen (Scotland, UK) and University of the Witwatersrand for financial support.

PY - 2015/8/25

Y1 - 2015/8/25

N2 - The effect of different catalyst preparation methods to make tin-platinum modified Mo/H-ZSM-5 zeolite catalysts for methane dehydroaromatization at 700 °C was investigated. The catalysts were prepared by both incipient wetness co-impregnation and sequential impregnation and calcined at 500 °C for 6 h. Catalysts prepared by the co-impregnation method showed a good platinum dispersion (10.8%), higher than found for the Pt/Sn and Sn/Pt sequentially impregnated catalysts (5.6% and 1.4%, respectively). Successive calcination treatments influenced the location of both tin and platinum in the catalyst and a decrease in platinum dispersion after reduction was evident from CO chemisorption studies. The order of sequentially loading platinum before or after tin had an effect on the electronic and structural properties of platinum as shown by XPS and FTIR studies. Different catalytic activities and aromatic selectivities were observed for the Pt/Sn and Sn/Pt catalysts. The co-impregnated Sn-Pt and the sequentially impregnated Pt/Sn catalysts showed high aromatic selectivity (>70%) and low coke selectivity (<20%). The decrease in coke selectivity is mainly dependent on the availability of platinum sites for hydrogenation of carbonaceous species.

AB - The effect of different catalyst preparation methods to make tin-platinum modified Mo/H-ZSM-5 zeolite catalysts for methane dehydroaromatization at 700 °C was investigated. The catalysts were prepared by both incipient wetness co-impregnation and sequential impregnation and calcined at 500 °C for 6 h. Catalysts prepared by the co-impregnation method showed a good platinum dispersion (10.8%), higher than found for the Pt/Sn and Sn/Pt sequentially impregnated catalysts (5.6% and 1.4%, respectively). Successive calcination treatments influenced the location of both tin and platinum in the catalyst and a decrease in platinum dispersion after reduction was evident from CO chemisorption studies. The order of sequentially loading platinum before or after tin had an effect on the electronic and structural properties of platinum as shown by XPS and FTIR studies. Different catalytic activities and aromatic selectivities were observed for the Pt/Sn and Sn/Pt catalysts. The co-impregnated Sn-Pt and the sequentially impregnated Pt/Sn catalysts showed high aromatic selectivity (>70%) and low coke selectivity (<20%). The decrease in coke selectivity is mainly dependent on the availability of platinum sites for hydrogenation of carbonaceous species.

KW - H-ZSM-5

KW - Methane dehydroaromatization

KW - Molybdenum

KW - Platinum

KW - Tin

UR - http://www.scopus.com/inward/record.url?scp=84938118173&partnerID=8YFLogxK

U2 - 10.1016/j.apcata.2015.06.035

DO - 10.1016/j.apcata.2015.06.035

M3 - Article

AN - SCOPUS:84938118173

SN - 0926-860X

VL - 503

SP - 218

EP - 226

JO - Applied Catalysis A: General

JF - Applied Catalysis A: General

ER -

Dehydroaromatization of methane over Sn-Pt modified Mo/H-ZSM-5 zeolite catalysts: Effect of preparation method

Abstract

Bibliographical note

Keywords

Access to Document

Other files and links

Fingerprint

Cite this