Effect of reaction conditions on the oxidative coupling of methane over doped MnOx-Na2WO4/SiO2 catalyst

Naseem S. Hayek, Grace J. Khlief, Faris Horani, Oz M. Gazit

Research output: Contribution to journalArticlepeer-review


The MnOx-Na2WO4/SiO2 mixed oxide is a highly promising catalyst for the oxidative coupling of methane to ethylene (OCM). But it seems that its catalytic performance still does not meet industrial requirements. Several additives were reported to promote its activity and selectivity such as Ti, Ce, La, etc. However, contradicting results were obtained in the different studies and the additives were not compared under the same reaction conditions. In this study, we tested several reported additives (Ti, Nb, Ce, and Sn) in OCM, which previously showed promising results, as well as additives (Ge and Fe) that were not examined before. Using these doped catalysts, it is shown that the improved performance and the long-term stability of these catalysts are a product of the specific reaction conditions, i.e. the extent of oxygen conversion and time on stream. We show that overall these catalyst systems are unstable and undergo severe deactivation that is masked if tested under conditions were the O2 is totally consumed. Finally, by characterizing spent catalysts, several possible deactivation mechanisms are briefly discussed.

Original languageEnglish
Pages (from-to)25-31
Number of pages7
JournalJournal of Catalysis
StatePublished - Aug 2019


  • Cristobalite
  • Ethylene
  • Manganese oxide
  • Metal oxide
  • Methane
  • OCM
  • Sodium tungstate

All Science Journal Classification (ASJC) codes

  • Catalysis
  • Physical and Theoretical Chemistry


Dive into the research topics of 'Effect of reaction conditions on the oxidative coupling of methane over doped MnOx-Na2WO4/SiO2 catalyst'. Together they form a unique fingerprint.

Cite this