高温下1-己烯在H-ZSM-5催化剂上的裂化反应机理和反应路径  

Cracking Reaction Mechanism and Reaction Pathway of1-Hexene Over H-ZSM-5 Catalyst at High Temperature

作　　者：韩月阳 杜令印 朱远 许友好 欧阳颖 HAN Yueyang;DU Lingyin;ZHU Yuan;XU Youhao;OUYANG Ying(SINOPEC Research Institute of Petroleum Processing Co.,Ltd.,Beijing 100083,China)

机构地区：[1]中石化石油化工科学研究院有限公司,北京100083

出　　处：《石油学报（石油加工）》2024年第3期610-618,共9页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：国家重点研发计划项目(2021YFA1501204)基金资助。

摘　　要：采用固定床反应器考察了1-己烯在反应温度为500~750℃范围内在H-ZSM-5沸石和石英砂上的裂化反应。在此基础上,建立了催化/热裂化占比模型,定量地讨论了高温下催化裂化和热裂化反应的关系。另外,根据1-己烯在H-ZSM-5沸石上裂化反应的产物分布,对其反应路径进行了推导和估算。结果表明:1-己烯在H-ZSM-5沸石上的高温反应以催化裂化为主。即使在750℃高温下,1-己烯通过催化裂化反应进行转化的占比仍然高达91.32%。产物中甲烷、乙烯和丙烯等主要来源于催化裂化反应,而不是热裂化反应。对1-己烯裂化反应路径的估算发现,双分子齐聚裂化反应占比由500℃时的74%下降到700℃时的0。单分子直接裂化反应有利于生成乙烯和丙烯等小分子烯烃,而双分子齐聚裂化反应有利于生成较大分子烯烃。高温下乙烯和丙烯产率较高的原因可能是高温促进了1-己烯的单分子直接裂化反应。The cracking reactions of 1-hexene over H-ZSM-5 zeolite and quartz sand at reaction temperatures from 500 to 750℃were investigated in a fixed bed reactor.On this basis,a catalytic/thermal cracking proportion model was established to quantitatively discuss the relationship between catalytic cracking and thermal cracking at high temperatures.In addition,the reaction pathway was deduced and estimated according to the products distribution of 1-hexene cracking over H-ZSM-5 zeolite.The results indicate that the high temperature reaction of 1-hexene over H-ZSM-5 zeolite is dominated by catalytic cracking.Even at 750℃,the ratio of 1-hexene feed converted by the catalytic cracking reaction is still as high as 91.32%.Methane,ethylene,and propylene in the products are mainly derived from catalytic cracking rather than thermal cracking reaction.It is found by estimating the cracking pathway of 1-hexene that the proportion of bimolecular oligomerization cracking reaction has been decreased from 74%at 500℃to 0 at 700℃.Monomolecular direct cracking is beneficial to the formation of small molecule olefins such as ethylene and propylene,while bimolecular oligomerization cracking is advantageous to the formation of larger molecule olefins.The reason for the high yield of ethylene and propylene at high temperatures may be that high temperature can promote the monomolecular direct cracking of 1-hexene.

关 键 词：1-己烯 高温 催化裂化反应 乙烯 丙烯 

分 类 号：TE624.4[石油与天然气工程—油气加工工程]