采用固体多核13C,27Al及29Si MAS NMR结合吸附气体Xe后的129Xe NMR,详细研究了乙烯和2-丁烯歧化生成丙烯反应过程中6%Mo/Hβ-Al2O3催化剂上积炭的类型和落位.结果表明,积炭以饱和烷烃为主,并随着反应的进行生成更多的支链烷烃,积炭主要...采用固体多核13C,27Al及29Si MAS NMR结合吸附气体Xe后的129Xe NMR,详细研究了乙烯和2-丁烯歧化生成丙烯反应过程中6%Mo/Hβ-Al2O3催化剂上积炭的类型和落位.结果表明,积炭以饱和烷烃为主,并随着反应的进行生成更多的支链烷烃,积炭主要分布在Hβ分子筛上,并主要落位在分子筛的交叉孔道处.展开更多
^(129)Xe NMR has been proven to be a powerful tool to investigate the structure of porousmaterials. Xenon is a monatomic noble gas which could be used as a probe due to theextremely sensitive to its local environment....^(129)Xe NMR has been proven to be a powerful tool to investigate the structure of porousmaterials. Xenon is a monatomic noble gas which could be used as a probe due to theextremely sensitive to its local environment. Optical pumping techniques for production ofhyperpolarized (HP) xenon have led to an increase of sensitivity up to orders of magnitudecompared with traditional ^(129)Xe NMR. This review summarizes the application of thistechnique in porous materials and heterogeneous catalysis in recent ten years, involving ofzeolites, metal-organic frameworks (MOFs), catalytic process and kinetics.展开更多
Purely siliceous MCM 41 with a narrow pore-size distribution , different pore size , high surface area was synthesized . As prepared , calcined and catalytically tested MCM 41 materials have been comprehensively chara...Purely siliceous MCM 41 with a narrow pore-size distribution , different pore size , high surface area was synthesized . As prepared , calcined and catalytically tested MCM 41 materials have been comprehensively characterized by N2 adsorption/desorption at 77K and 129Xe NMR . By adding mesitylene during the synthesis , the pore size of MCM 41 was enlarged to 5.2nm. The chemical shift in 129Xe NMR spectroscopy of adsorbed xenon indicates that the MCM 41 is one dimensional pore channels .展开更多
中国科学院大连化学物理研究所催化基础国家重点实验室包信和研究小组提出了一种将激光诱导超极化^129Xe技术与^13C MAS NMR结合的新型原位表征技术，并成功应用于纳米分子筛腔中分子的吸附和反应动力学研究．辅以作证，首次在模拟催化...中国科学院大连化学物理研究所催化基础国家重点实验室包信和研究小组提出了一种将激光诱导超极化^129Xe技术与^13C MAS NMR结合的新型原位表征技术，并成功应用于纳米分子筛腔中分子的吸附和反应动力学研究．辅以作证，首次在模拟催化反应条件下系统研究了甲醇分子在CHA分子筛孔道的转化过程．结果表明：反应中间产物可被^13C MAS NMR有效检测到，而甲醇分子在纳米分子筛空腔内的吸附和反应动力学过程也可被接近真实反应下的一维和二维耦合^129Xe MAS NMR观测到．展开更多
文摘采用固体多核13C,27Al及29Si MAS NMR结合吸附气体Xe后的129Xe NMR,详细研究了乙烯和2-丁烯歧化生成丙烯反应过程中6%Mo/Hβ-Al2O3催化剂上积炭的类型和落位.结果表明,积炭以饱和烷烃为主,并随着反应的进行生成更多的支链烷烃,积炭主要分布在Hβ分子筛上,并主要落位在分子筛的交叉孔道处.
基金This work was supported by Natural Science Foundation of china(grant no.22022202,21972142,91745109,91545104)the LiaoNing Revitalization Talents Program(grant no.XLYC1807227)This work is dedicated to Professor Xiuwen Han on the occasion of her 80th birthday。
文摘^(129)Xe NMR has been proven to be a powerful tool to investigate the structure of porousmaterials. Xenon is a monatomic noble gas which could be used as a probe due to theextremely sensitive to its local environment. Optical pumping techniques for production ofhyperpolarized (HP) xenon have led to an increase of sensitivity up to orders of magnitudecompared with traditional ^(129)Xe NMR. This review summarizes the application of thistechnique in porous materials and heterogeneous catalysis in recent ten years, involving ofzeolites, metal-organic frameworks (MOFs), catalytic process and kinetics.
文摘Purely siliceous MCM 41 with a narrow pore-size distribution , different pore size , high surface area was synthesized . As prepared , calcined and catalytically tested MCM 41 materials have been comprehensively characterized by N2 adsorption/desorption at 77K and 129Xe NMR . By adding mesitylene during the synthesis , the pore size of MCM 41 was enlarged to 5.2nm. The chemical shift in 129Xe NMR spectroscopy of adsorbed xenon indicates that the MCM 41 is one dimensional pore channels .
文摘中国科学院大连化学物理研究所催化基础国家重点实验室包信和研究小组提出了一种将激光诱导超极化^129Xe技术与^13C MAS NMR结合的新型原位表征技术，并成功应用于纳米分子筛腔中分子的吸附和反应动力学研究．辅以作证，首次在模拟催化反应条件下系统研究了甲醇分子在CHA分子筛孔道的转化过程．结果表明：反应中间产物可被^13C MAS NMR有效检测到，而甲醇分子在纳米分子筛空腔内的吸附和反应动力学过程也可被接近真实反应下的一维和二维耦合^129Xe MAS NMR观测到．
