Low-Temperature Transformation of Methane to Methanol on Pd1 O4 Single Sites Anchored on the Internal Surface of Microporous Silicate

Abstract

Direct conversion of methane to chemical feedstocks such as methanol under mild conditions is a challenging but ideal solution for utilization of methane. Pd₁ O₄ single-sites anchored on the internal surface of micropores of a microporous silicate exhibit high selectivity and activity in transforming CH₄ to CH₃ OH at 50-95 °C in aqueous phase through partial oxidation of CH₄ with H₂ O₂ . The selectivity for methanol production remains at 86.4 %, while the activity for methanol production at 95 °C is about 2.78 molecules per Pd₁ O₄ site per second when 2.0 wt % CuO is used as a co-catalyst with the Pd₁ O₄ @ZSM-5. Thermodynamic calculations suggest that the reaction toward methanol production is highly favorable compared to formation of a byproduct, methyl peroxide.

Keywords: methane; methanol; oxidation; palladium; single-sites.