Photochemical conversion of methane

Methane was converted by the photochemical reaction with water vapor at temperatures lower than 100 °C and at atmospheric pressure. The activation of the conversion of methane was initiated by the hydroxyl radical formed by the photolysis of water vapor. The major product was methanol (selectivity, ~70% at 90 °C) followed by formic acid (11%), ethanol (5%), formaldehyde (5%), acetone (4%) and acetic acid (3%). The activation energy for the formation of methanol was estimated as 5.6 kcal mol−1, and the generalized reaction pathway is discussed.