李渊,杨晨芳

• 1:天津工业大学省部共建分离膜与膜过程国家重点实验室
• 2:天津工业大学化学工程与技术学院

摘要(Abstract)：

为合成更高性能的多级孔SAPO-34分子筛催化剂，使用四乙基氢氧化铵（TEAOH）和三乙胺（TEA）为混合模板剂，以聚乙二醇（PEG1500）为软模板剂，采用水热合成法合成多级孔SAPO-34分子筛催化剂。考察软模板剂的添加时间对多级孔SAPO-34分子筛合成的影响；采用XRD、SEM、FT-IR、NH3-TPD、XRF和BET等多种手段对样品进行表征，并使用固定床反应器对其MTO催化性能进行评价。结果表明：聚乙二醇作为介孔导向剂和结晶抑制剂，不仅可以在微孔结构中引入介孔，还可以起到抑制晶体结晶的作用；不同时间加入软模板剂对分子筛晶体的成核和生长产生不同结果，晶化4 h和22 h时添加软模板剂得到的产品形貌规整且不存在无定形颗粒，晶化8 h和14 h时添加软模板剂得到的产品晶体存在缺陷且有无定形颗粒存在；改变软模板剂添加时间，对分子筛的酸性会产生不同影响，晶化4 h时添加PEG1500得到的样品具有最优的催化效果，表现出最长的催化寿命（180 min）以及最高的双烯选择性（91.86%）。

关键词(KeyWords)： 软模板剂;多级孔;分子筛;结晶;酸性;甲醇制烯烃(MTO)

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金资助项目（91745116）

作者(Author): 李渊,杨晨芳

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