Low temperature oxidative coupling of methane using highly oxidized palladium supported on cerium oxide catalyst

Abstract

Oxidative coupling of methane is important issue for modern-day chemical industry. High reaction temperature was required to cleave the first C-H bond of methane on the heterogeneous catalyst. Here, small Pd nanoparticles deposited onto $CeO_2$ was synthesized by deposition-precipitation method. As-made Pd/$CeO_2$ was hydrothermally treated at $750^\circ c$ to make active Pd/$CeO_2$ catalyst. The highly oxidized Pd/$CeO_2$ catalyst was used for oxidative coupling of methane reaction to produce ethane at low temperature ($\leq300^\circ c$). The Pd/$CeO_2$ was characterized by X-ray fine structure analysis (XAFS), CO chemisorption, and X-ray diffraction (XRD). Pd/$CeO_2$ showed the best activity and selectivity of ethane by compared various noble metal and support. High oxidation state of Pd/$CeO_2$ and small-sized Pd nanoparticles are important to improve the oxidative coupling of methane reaction.