Abstract: The reaction mechanism of decalin under the action of different types of catalysts is reviewed. Decalin is converted to free radicals by carboanion and then cracked by free radical mechanism under the action of lattice oxygen and adsorbed oxygen species on metal oxide catalysts. Decalin forms carbocation on the B acid center of solid acid catalyst, and then it reacts with a carbocation mechanism. Advantages and disadvantages of different pyrolysis catalysts were analyzed. The metal oxide catalysts were resistant to hydrothermal and high temperature, and could inhibit coking, but had no promoting effect on greatly decreasing reaction temperature and increasing propylene yield. Solid acid catalyst has acid center and unique pore structure, which can greatly reduce the reaction activation energy and flexibly adjust the proportion of low carbon olefins. Finally,the effects of different process conditions on decalin cracking reaction were listed.

Key words: decalin, deep catalytic cracking, reaction mechanism, catalyst, technology