草酸处理对USY分子筛脱烯烃性能的影响及催化剂失活原因分析  

Deolefinization performance of oxalic acid treated USY zeolites and the analysis of catalyst deactivation

作　　者：侯敏 周亚新 石张平 祁晓岚 孔德金 Hou Min;Zhou Yaxin;Shi Zhangping;Qi Xiaolan;Kong Dejin(State Key Laboratory of Green Chemical Engineering and Industrial Catalysis,SINOPEC Shanghai Research Institute of Petrochemical Technology Co.,Ltd.,Shanghai 201208,China)

机构地区：[1]中石化(上海)石油化工研究院有限公司,绿色化工与工业催化国家重点实验室,上海201208

出　　处：《工业催化》2024年第5期46-55,共10页Industrial Catalysis

摘　　要：分子筛催化重整生成油脱烯烃技术工艺路线简单,可大幅度缩减固废。研究草酸处理对USY分子筛骨架结构、孔结构以及酸性质的影响。以含微量苯乙烯的甲苯为模型原料,考察酸处理对USY沸石催化脱烯烃反应性能和稳定性的影响。采用气相色谱-质谱联用仪对反应原料和产物组成进行分析。结果表明,草酸处理可脱除USY骨架铝原子,降低分子筛酸强度和酸量;苯乙烯可以与甲苯发生烷基化反应,也可以自身发生二聚反应,还可能发生副反应生成多环芳烃堵塞孔道,引起催化剂失活;采用草酸处理后,二聚反应和副反应被显著削弱,烷基化反应增强,催化剂寿命延长,催化剂脱烯烃反应稳定性显著提升。The molecular sieve catalytic deolefinization of reformate is a simple route and can significantly reduce the solid waste.Here we investigated the influence of oxalic acid post-treatment on the framework structure,pore structure,and acid properties of USY molecular sieves in detail.The catalytic deolefinization performance and stability of USY zeolites before and after acid treatment were investigated by using toluene containing trace amounts of styrene as a model feed.The composition of the feeds and products were analyzed by gas chromatography-mass spectrometry.The results showed that the oxalic acid treatment can result in framework-dealumination of USY,thus reduce the acid strength and acid content.Besides alkylation with toluene,or self-dimerization,the styrene can undergo side reactions to generate polycyclic aromatic hydrocarbons to block the zeolite pores,which can cause catalyst deactivation.However,the self-dimerization and side reactions were significantly weakened after modification with oxalic acid,at the same time,the alkylation reaction was significantly enhanced,thus the catalyst life was extended,and the stabi-lity of catalytic deolefinization was significantly improved.

关 键 词：催化化学 重整生成油 苯乙烯 USY分子筛 酸处理 催化脱烯烃 

分 类 号：TQ426.6[化学工程] O643.36[理学—物理化学]