Oxidative coupling of methane over NbO (p-type) and Nb2O5 (n-type) semiconductor materials

Date

1996-01-01

Author

Erarslanoglu, Y
Onal, I
Doğu, Timur
Senkan, S

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Oxidative coupling of methane to higher hydrocarbons was investigated using two types of semiconductor catalysts, NbO (p-type) and Nb2O5 (n-type) at 1 atm pressure. The ratio of methane partial pressure to oxygen partial pressure was changed from 2 to 112 and the temperature was kept at 1023 K in the experiments conducted in a cofeed mode. The results indicated a strong correlation between C-2+ selectivity performance and the electronic properties of the catalyst in terms of p- vs. n-type conductivity. The p-type semiconductor catalyst, NbO, had a larger selectivity (e.g. 95.92%) over the n-type Nb2O5 catalyst (23.08%) both at the same methane conversion of 0.64%. Catalyst characterization via X-ray diffraction, TGA and reaction studies indicated that NbO was transformed to Nb2O5 during the course of the reaction which limits catalyst life.

Subject Keywords

General Chemistry, Catalysis

URI

https://hdl.handle.net/11511/62943

Journal

CATALYSIS LETTERS

DOI

https://doi.org/10.1007/bf00806571

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

Y. Erarslanoglu, I. Onal, T. Doğu, and S. Senkan, “Oxidative coupling of methane over NbO (p-type) and Nb2O5 (n-type) semiconductor materials,” CATALYSIS LETTERS, pp. 215–218, 1996, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/62943.