分子筛孔结构对正己烷催化裂解性能的影响

石油炼制与化工 ›› 2017, Vol. 48 ›› Issue (8): 68-72.

分子筛孔结构对正己烷催化裂解性能的影响

冯敏超,周晓龙,李承烈,赵基钢

华东理工大学石油加工研究所

收稿日期:2017-01-19 修回日期:2017-02-27 出版日期:2017-08-12 发布日期:2017-07-19
通讯作者: 赵基钢 E-mail:zjg@ecust.edu.cn
基金资助:
国家高科技研究发展计划863项目

STUDY ON INFLUENCE OF ZEOLITE PORE STRUCTURES ON CATALYTIC CRACKING OF N-HEXANE

Received:2017-01-19 Revised:2017-02-27 Online:2017-08-12 Published:2017-07-19
Contact: Jigang Zhao E-mail:zjg@ecust.edu.cn
Supported by:

摘要/Abstract

摘要： 采用小型固定床实验装置考察了正己烷在4种分子筛上的催化裂解反应性能。结果表明：孔结构对正己烷催化裂解产物分布和积炭失活有着显著的影响；在所考察的4种分子筛中，孔径越小，越有利于单分子裂解，越不利于氢转移反应，乙烯和丙烯的选择性越高；ZSM-35上乙烯和丙烯的初始选择性虽然最高，但其积炭失活较严重，而ZSM-5分子筛表现出了较好的低碳烯烃选择性和抗积炭性，其双烯选择性为45.06%，且反应4 h后转化率仅下降4%左右。

关键词: 孔结构, 正己烷, 催化裂解, 低碳烯烃

Abstract: Catalytic cracking of n-hexane was conducted in a fixed-bed reactor on four zeolites with different pore structures. The results show that pore structures of zeolites play significant roles in product distribution and deactivation of catalyst due to carbon deposition and that the smaller the pore size of the zeolite, the more conducive to the monomolecular cracking, the higher the selectivity of ethylene and propylene, due to a suppression of the hydrogen transfer reaction. The highest initial selectivity of ethylene and propene are gained on ZSM-35, but it is rapidly inactivated, while the ZSM-5 exhibits better selectivity (ethylene and propylene of 45.06%) and anti-carbon deposition ability among these zeolites. The reduction of conversion is only about 4% after 4 h.

Key words: pore structure, hexane, catalytic cracking, light olefin

中图分类号:

冯敏超周晓龙李承烈赵基钢. 分子筛孔结构对正己烷催化裂解性能的影响[J]. 石油炼制与化工, 2017, 48(8): 68-72.

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