促进剂法H-SSZ-13分子筛的合成及其对MTO反应性能的影响  

H-SSZ-13 molecular sieve synthesized by introducing accelerant and its effect on reactivity of MTO

作　　者：李渊[1,2] 王文婷[1] 赵飞[1] 谭小耀[1] 

机构地区：[1]天津工业大学环境与化学工程学院,天津300387 [2]天津众智科技有限公司,天津300456

出　　处：《天津工业大学学报》2015年第6期35-40,共6页Journal of Tiangong University

基　　金：国家自然科学基金资助项目(21176187);天津市自然科学基金资助项目(14JCTPJC00559)

摘　　要：以N,N,N-三甲基-1-金刚烷基氢氧化铵为模板剂,在添加促进剂的条件下,采用水热合成法合成了SSZ-13分子筛催化剂,发现促进剂的加入明显降低了模板剂的用量并且使分子筛的合成周期缩短为2 d.通过XRD、SEM、NH_3-TPD手段对催化剂进行了相关表征.以降低SSZ-13分子筛在甲醇制烯烃(MTO)反应过程中的主要副产物丙烷的选择性为目标,考察了反应条件对SSZ-13分子筛在MTO反应中催化性能的影响.结果表明:温度的升高、空速的增加、醇水比的降低均可明显降低丙烯氢转移反应速率,从而明显降低丙烷生成,提高低碳烯烃选择性.当反应温度为400℃、空速为20 h^(-1)、m(甲醇)∶m(水)=50∶50时,反应初期低碳烯烃选择性可提高至85.08%,平均低碳烯烃的选择性高达86.93%,甲醇处理量可达到5.28 g.通过与商品化DMTO催化剂的对比发现,在适当的MTO工艺条件下,所合成的SSZ-13催化剂可以达到商品化催化剂的性能.SSZ-13 were prepared hydrothermally with N,N,N-trimethyladamantammonium hydroxide (TMAdaOH) as the templating agent. The content of templating agent was decreased and the reaction time was further shortened to 2 d by introducing accelerant. The sample was characterized by XRD, SEM and NH3-TPD. In order to reduce the propane selectivity, the influence of reaction conditions on the performance of SSZ-13 in the MTO reaction were studied. It was indicated that the increasing of temperature, space velocity, diluent water, could obviously reduce propane selectivity, improve the light olefin selectivity. The best catalytic performance with the average light olefins selectivity of 86.93% and methanol capacity of 5.28 g was observed when the conditions on the MTO reaction over SSZ-13 were with the reaction temperature of 400℃, weight hourly space velocity (WHSV) of 20 h-1, m(CH3OH)/m(H2O)=50/50. By contrast with commercialized DMTO catalyst, it was found that SSZ-13 catalyst could achieve the performance of commercialized catalyst under appropriate MTO process.

关 键 词：H-SSZ-13 促进剂 分子筛 甲醇制烯烃(MTO) 反应条件 

分 类 号：TQ203[化学工程—有机化工] O643.36[理学—物理化学]