Continuous methane to ethane conversion using gaseous oxygen on ceria-based Pd catalysts at low temperatures

Abstract

Methane upgrading into more valuable chemicals has been a promising challenge. It was previously reported that highly oxidized Pd/CeO2 could produce ethane from methane. Here, we enhanced the ethane productivity by controlling oxygen mobility of the catalyst support and adding water adsorbents. Pd/Ce1-xPdxO2-y catalyst, in which Pd atom was doped at the ceria support, showed enhanced oxygen activation and oxygen transfer, improving the ethane productivity from 0.04 mol(C2H6)/mmol(SurfacePd)/h in Pd/CeO2 to 0.57 mol(C2H6)/mmol(SurfacePd)/h in Pd/Ce1-xPdxO2-y. In order to remove the water produced from methane oxidation, zeolite 13X was physically mixed with Pd/Ce1-xPdxO2-y. The water adsorbent could increase the ethane production significantly, especially at low temperatures. The ethane yield of 0.30 % could be obtained at 290 degrees C using gaseous O-2 as an oxidant. This work can provide useful ways to enhance the yield of value-added products in oxidative methane conversion.