Experiments of n-heptane catalytic pyrolysis over zeolite catalysts were conducted on a laboratory fixed fluidized bed reactor. The effects of reaction temperature, the number of active site and zeolite type of the catalyst on product slate were investigated, as well as the initiation of chain reaction was analyzed. Results showed that during n-heptane catalytic pyrolysis over ZRP zeolite catalyst, the positions and progress of C-C bond attacked by a proton in the initiation reaction was varied with reaction temperature obviously. With the increase of reaction temperature, the protonized position shifted from the C-C bond adjacent to center to that located at C-terminal, leading to various product slates. With the increase of activity (acidity) sites in catalyst, the initiation of chain reaction could be speeded up and the attacked positions tended to the center of carbon chain. Compared with Y and Beta zeolite catalysts, ZRP zeolite catalyst had more strong Bronsted acid sites, which was in favor of initiating chain reaction occurring at the center of carbon chain.%采用小型固定流化床(ACE)装置考察了反应温度、分子筛催化剂的活性中心数和分子筛类型对正庚烷催化裂解反应产物的影响,并对裂解链引发反应进行了分析.结果表明,在ZRP分子筛催化剂催化正庚烷裂解反应中,反应温度可以明显改变正庚烷裂解反应的链引发反应的位置和发生程度；提高反应温度,链引发位置从碳链中心位置的C-C键向靠近碳链端位的C-C键移动,导致不同的产物分布；催化剂活性中心数的增加可以提高正庚烷裂解反应的链引发反应发生程度,并倾向于在碳链中心位置C-C键发生；与Y分子筛和Beta分子筛催化剂相比,具有更多较强Br(o)nsted酸的ZRP分子筛更有利于链引发反应,并倾向于在碳链中心的C-C键发生.
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