The tar decomposition activities of eight catalysts including Fe based catalyst, three Ni based catalyst, alumina, 5A molecular sieve, CaO catalyst, quartz catalysts were compared in a fixed-bed catalytic reactor, using a simulate high temperature coal gas 1-methylnaphthalene was used as a tar model compound All these catalysts showed to be active and useful for tar cracking reactions, and deactivations of Fe based, three Ni based and 5A molecular sieve catalyst were not found within 10 h reaction time with space velocity of 3000 h -1 at temperature of 550℃ Especially, with increasing temperature, the conversion of 1-methylnaphthalene was improved, and its conversion decreased with increasing the space velocity Catalytic reactivities for Ni-3 catalyst remained unchanged within 100 h reaction time with space velocity of 3000 h -1 at temperature of 550℃ At same time, Ni-3 catalyst was also found to be the effective catalyst for benzene conversion at 550℃ and
