Support oxide tuning of MnOx-Na2WO4 catalysts enables low-temperature light-off of OCM

Authors：Si, Jiaqi; Sun, Weidong; Zhao, Guofeng^*; Lu, Yong^*

Source：Fuel, 2022, 311: 122539.

DOI：10.1016/j.fuel.2021.122539

• Oxidative coupling of methane
• Ethylene
• MnOx-Na2WO4 catalyst
• Low-temperature light-off
• Redox cycle

The MnOx-Na2WO4 catalyst for oxidative coupling of methane (OCM) is highly attractive but its high light-off temperature (>800 degrees C) is a major obstacle for commercialization. In-depth understanding of reaction light-off relevant chemistry is particularly desirable. We explored the OCM light-off over several metal-oxide-supported MnOx-Na2WO4 catalysts. As CH4 conversion above 15% with acceptable C2-3 selectivity is considered as the sign of OCM light-off, support-dependent OCM light-off is clearly observed over MnOx-Na2WO4 supported on SnO2 (660 degrees C), TiO2 (670 degrees C), MgO (690 degrees C), and ZnO (720 degrees C), being tightly linked with the redox rate of Mn3+(or Mn4+) <-> Mn2+ cycle governed by support oxides.

• Institution
  y