Catalytic Performance of n-Heptane Cracking to Light Olefins over Hierarchical ZSM-5 Zeolites
PAN Xiaoyan1, HOU Keke1, ZHENG Yifan2, SHI Huibing1, ZHANG Fengqi 1, WANG Yaowei 1, ZHU Kake 2, LIU Jichang2
1. Shandong Chambroad Petrochemicals Company Limited, Binzhou 256500, China;
2. State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
Abstract：Catalytic performance of zeolites in naphtha cracking to olefins was influenced by both acidity and diffusion properties of catalysts, which could be optimized to enhanced catalyst stability and promoted light olefin selectivity. The hierarchical ZSM-5 zeolites with Si/Al (molar ratio) of 30 and 50 were prepared by the solvent evaporation induced self-assembly method. The modified ZSM-5 zeolites by P and La were evaluated as n-heptane catalytic cracking catalyst, and compared with conventional ZSM-5. The results demonstrated a high catalytic stability of the prepared nano assembled multi-stage porous zeolite in n-heptane cracking reaction to olefins, and light olefin (ethylene and propylene, in particular propylene) selectivity, with respect to microporous control samples. The increase of Si/Al ratio and the hierarchical porosity of zeolites were conducive to the occurrence of mono-molecule cracking reaction and also inhibit the occurrence of side reactions such as hydrogen transfer, so as to reduce the loss of olefins.
PAN Xiaoyan,HOU Keke,ZHENG Yifan et al. Catalytic Performance of n-Heptane Cracking to Light Olefins over Hierarchical ZSM-5 Zeolites[J]. Chemical Reaction Engineering and Technology, 2022, 38(1): 23-31.
