Methane oxidation using silica-supported N-bridged di-iron phthalocyanine catalyst

Methane oxidation in water using hydrogen peroxide with a μ-nitrido iron phthalocyanine complex grafted on silica has been investigated in detail. Methyl hydroperoxide is identified as the main primary reaction product from methane oxidation. The catalyst is unstable under reaction conditions and this is discussed. However, the unmodified silica support is also found to be active for this reaction, and in particular, a Fe/SiO2 catalyst prepared by wet impregnation is also found to be as effective as the μ-nitrido iron phthalocyanine complex grafted on silica, with higher selectivity to useful oxygenates (>80%) and displays minimal leaching or instability. A method for the reliable quantification of CO2 in both the gas and aqueous phase is reported as this presents a key experimental difficulty in the oxidation of methane in aqueous media.