Catalysis Letters

, Volume 38, Issue 3–4, pp 215–218 | Cite as

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

  • Yesim Erarslanoglu
  • Isik Onal
  • Timur Dogu
  • Selim Senkan
Article
  • 92 Downloads

Abstract

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 C2+ 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.

Keywords

methane oxidative coupling semiconductor-type catalysts n-type and p-type semiconductors Nb2O5 NbO 

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Copyright information

© J.C. Baltzer AG, Science Publishers 1996

Authors and Affiliations

  • Yesim Erarslanoglu
    • 1
  • Isik Onal
    • 1
  • Timur Dogu
    • 1
  • Selim Senkan
    • 2
  1. 1.Department of Chemical EngineeringMiddle East Technical UniversityAnkaraTurkey
  2. 2.Department of Chemical EngineeringUniversity of CaliforniaLos AngelesUSA

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