CO2 oxidative coupling of methane using an earth-abundant CaO-based catalyst

Abstract

CO2 oxidative coupling of methane has been achieved by using CO2 as the oxidant. We explored various catalysts with the capability of producing C2,3 hydrocarbons and found that the use of a CaO-based oxide with sodium (Na) and chloride (Cl) allowed for remarkable direct methane conversion with a C2,3 yield of 6.6% at 950\u2009°C. Microstructural characterisations showed that the optimal sample contained sodium carbonate (Na2CO3) covered with fine calcium oxide particles with chloride doping. Interestingly, sodium carbonate acted as a molten salt catalyst in this scenario. The synthesised active components are earth-abundant and can increase the possibility of achieving higher yields of hydrocarbons.