不同模板剂合成SAPO-35分子筛及其甲醇制烯烃催化性能  

Synthesis of SAPO-35 molecular sieves with different structure-directing agents and their catalytic performance in the conversion of methanol to olefins

作　　者：梁妮 康蕾[1] 王钰佳[1] 王海彦[1] 白英芝[1] 韩乔 孙娜[1] LIANG Ni;KANG Lei;WANG Yujia;WANG Haiyan;BAI Yingzhi;HAN Qiao;SUN Na(School of Petrochemical Engineering,Liaoning Petrochemical University,Fushun 113001,China)

机构地区：[1]辽宁石油化工大学石油化工学院,辽宁抚顺113001

出　　处：《燃料化学学报(中英文)》2025年第4期515-526,共12页Journal of Fuel Chemistry and Technology

基　　金：辽宁省教育厅基本科研基金(LJKQZ20222284,JYTMS20231433,JYTMS20231449);辽宁省科学技术计划(2022-BS-290);辽宁石油化工大学引进人才科研启动基金(2021XJJL-019);辽宁石油化工大学引进人才科研启动基金(2021XJJL-020)资助。

摘　　要：以六亚甲基亚胺(HMI)和N-甲基哌啶(NMP)为模板剂,采用水热合成法制备了一系列不同硅铝比((n(SiO_(2))/n(Al_(2)O_(3)))的SAPO-35分子筛。采用XRD、SEM、FT-IR、NH_(3)-TPD、XRF、固体核磁以及N_(2)吸附-脱附等方法对合成的分子筛样品进行表征,并对其甲醇制烯烃(MTO)催化性能进行了比较研究。表征结果表明,分子筛的结晶度及酸密度随初始凝胶中硅铝比的增加呈现出先增大后减小的趋势,且当硅铝比为0.3时所合成的SAPO-35-0.3(HMI)样品具有较高的结晶度、较大的比表面积以及适宜的酸分布。与HMI为结构导向剂合成的SAPO-35-HMI相比,在相同硅铝比投料下、新型NMP为结构导向剂合成的SAPO-35-NMP样品用于MTO反应时,其催化稳定性明显改善,且对小分子烯烃具有较好的择形选择性,双烯选择性提高至81.3%,乙烯选择性达到45.6%,远超过丙烯。A series of SAPO-35 molecular sieves with different SiO_(2)/Al_(2)O_(3)ratios were synthesized by hydrothermal method using hexamethylene imine(HMI)and N-methylpiperidine(NMP)as the structure-directing agent(SDA).The synthesized SAPO-35 molecular sieves were characterized by XRD,SEM,FT-IR,NH_(3)-TPD,XRF and N_(2)sorption and their catalytic performance in the conversion of methanol to olefins(MTO)was comparatively investigated.The results indicated that the crystallinity and acid density of the SAPO-35 molecular sieves increase first and then decrease with the increase of the SiO_(2)/Al_(2)O_(3)ratio in the initial gel;in particular,the SAPO-35-0.3(HMI)sample with a SiO_(2)/Al_(2)O_(3)ratio of 0.3 displays a high crystallinity,large surface area and suitable acid distribution as a catalyst in MTO.Compared with the SAPO-35-HMI sample synthesized with HMI as SDA,the SAPO-35-NMP sample having the same SiO_(2)/Al_(2)O_(3)ratio but synthesized using new NMP as SDA exhibits much better catalytic stability and higher selectivity to light olefins in MTO;the selectivity to ethene+propene reaches 81.3%,where ethene accounts for more than 50%,far surpassing propene.

关 键 词：SAPO-35分子筛 模板剂 六亚甲基亚胺 N-甲基哌啶 甲醇制烯烃 

分 类 号：TQ426.61[化学工程]