NO_x-catalyzed partial oxidation of methane and ethane to formaldehyde by dioxygen

A NO_x-catalyzed process for the oxidation of methane and ethane to formaldehyde by dioxygen was presented. At 600°C in the presence of a stoichiometric amount of dioxygen (NO: O₂ = 2), NO_x will catalyze the conversion of both methane and ethane to formaldehyde in relatively good yields. When partial oxidation of methane was carried out at 525°C in an excess of dioxygen, > 2% CH₃NO₂ was formed. Increasing the temperature to ∼ 600°C prevented CH₃NO₂ formation. The yield of oxygenates from methane was over 11%. The yield increased to over 16% when 0.7% of ethane was added to the gas mixture. The yield of oxygenates from ethane was over 24%. A catalytic cycle involving NO₂ as the C-H activating species was proposed.