Photoinduced non-oxidative coupling of methane proceeded over H-form. mordenite and ZSM-5. The major product was C2H6, and the stoichiometric formation of H-2 was also revealed. The effects of the pretreatment temperature, Al content and H+ exchange level upon the activity suggested that the active sites were highly isolated framework Al-O units interacting with no metal cations. (C) 2002 Published by Elsevier Science B.V.