核壳结构ZSM-5/MCM-35分子筛的可控合成及其对MTP反应空间限域效应研究

项目名称： 核壳结构ZSM-5/MCM-35分子筛的可控合成及其对MTP反应空间限域效应研究

项目编号： No.U1510109

项目类型： 联合基金项目

立项/批准年度： 2016

项目学科： 有机化学

项目作者： 韩德志

作者单位： 中国科学院青岛生物能源与过程研究所

项目金额： 55万元

中文摘要： 甲醇制丙烯（MTP）是从非石油路线获得丙烯的重要途径之一，然而，由于ZSM-5催化剂本征孔道结构和过多外表面酸性位的原因，该过程仍存在丙烯的收率较低和催化剂寿命较短的问题。本项目拟采用二次生长法在ZSM-5分子筛的表面构建纯硅MCM-35壳层结构，制备核壳ZSM-5/MCM-35分子筛，在MTP反应中实现对反应产物空间限域择形，提高丙烯收率，同时覆盖ZSM-5分子筛的外表面酸性位，防止产物通过二次反应在分子筛外表面产生积碳，延长催化剂寿命。通过控制合成条件，探究壳层在核相上包覆度和厚度的调控规律；通过微反评价和色谱产物分析，结合分子筛的表征测试结果，研究核壳分子筛纯硅MCM-35壳层的空间限域效应对MTP产物分布的影响规律，探明构效关系；研究积碳失活行为以及反应再生性能；为设计性能更加优异的MTP催化剂奠定理论基础。

中文关键词： 核壳结构；分子筛；可控合成；甲醇制丙烯；空间限域作用

英文摘要： Methanol to propylene (MTP) is one of the important ways to obtain propylene from non-petroleum route. However, due to the intrinsic pore structure and abundant acid sites in external surface of the ZSM-5 catalyst, this process still has some disadvantages, such as low propylene yield and short catalyst lifetime. In this proposal, the core-shell ZSM-5/MCM-35 zeolite with pure silica MCM-35 shell will be prepared by using secondary growth method. The spatially confined effect of core-shell ZSM-5/MCM-35 zeolite will dramatically change the products distribution in MTP reaction to enhance the yield of propylene, meanwhile, the introduction of MCM-35 shell can shut down the secondary reaction of the products by covering the acid sites in external surface of core ZSM-5 to extend the catalyst lifetime. The control principle of the coverage degree and the thickness of the MCM-35 shell will be revealed by optimizing the synthesis conditions. The spatially confined effect of core-shell ZSM-5/MCM-35 zeolite on the products distribution in MTP reaction will be systematically studied by analyzing the results of the micro-reactor evaluation and the characterization of the zeolite to explore the structure-activity relationship. A detailed study of the carbon deposition behavior and reaction regeneration performance of the zeolite will be conducted. The results obtained in this project will lay a theoretical foundation for developing new MTP catalyst with excellent performance.

英文关键词： Core-shell structure;Zeolite;Controllable synthesis;Methanol to propylene;Spatially confined effect