【作者】 孙启明； 喜冬阳； 王宁； 李旭； 于吉红；

【Author】 Qiming Sun;Dongyang Xi;Ning Wang;Xu Li;Jihong Yu;State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry,Jilin University;

【机构】 吉林大学无机合成与制备化学国家重点实验室；

【摘要】 分子筛因其规则的孔道结构以及适宜的酸性在催化领域有着广泛的应用[1]。具有CHA拓扑结构的SAPO-34分子筛由于其优异的低碳烯烃选择性,成为最好的MTO反应催化剂之一[2]。但是,SAPO-34分子筛在MTO反应中容易产生积碳,堵塞孔道,降低其催化寿命。因此,采取不同的方式对SAPO-34进行改性,延长催化剂寿命,并进一步提高产物中低碳烯烃的选择性,具有重要的理论和实际意义。我们通过优化合成方法,水热条件下,成功制备了薄片状纳米SAPO-34催化剂,具有极高的催化寿命(>1200min,WHSV=2h-1),并利用3D EDT技术解析了其晶体结构;通过HF原位生长刻蚀方法,以及使用有机硅烷作为介孔结构导向剂方法成功制备了微孔大孔,微孔介孔复合的多级结构SAPO-34催化剂,催化测试结果表明多级孔的引入能够显著提升低碳烯烃选择性以及延长催化寿命。更多还原

【Abstract】 Silicoaluminophosphate molecular sieve SAPO-34 with the topological structure of CHA has been intensively studied as the most excellent catalyst for the methanol-to-olefin(MTO) conversion. However, the rapid deactivation due to the limitation of mass transport reduces the catalytic lifetime. Hence, overcoming the inherent diffusion limitations and retarding coke deposition are of significance to prolong the catalytic activity. Herein, we successfully synthesized nano sheet-like SAPO-34 which exhibited so far the longest catalytic lifetime(>1200min, WHSV=2h-1). In addition, we also successfully synthesized hierarchically macroporous and mesoporous SAPO-34 catalysts which showed the enhanced selectivity of light olefins and prolonged catalytic lifetime.更多还原