摘要
使用固体高分辨^(27)Al MASNMR技术研究了改良HZSM-5分子筛在不同预处理条件及催化反应与再生时结构热稳定性。结果表明,预处理条件对HZSM-5骨架的热稳定性有着明显影响。骨架脱铝顺序为:水热处理>热处理;GaHZSM-5>HZSM-5》ZnHZSM-5。水热处理样品HZSM-5,GaHZSM-5在反应后非骨架铝重新迁入了沸石骨架,即存在“反应补铝”效应。
The structure thermal stability of modified HZSM-5 under different pretreatment condi-tions, catalytic reactions and reproduction has been studied by high-resolution solid-state NMRusing ^(27)Al as probes. The results showed that the pretreatment condition has an apparenteffect on the structure thermal stability. The framework dealumination is in the following order:hydrothermal treatment>thermal treatment; GaHZSM-5>HZSM-5>ZnHZSM-5. After reaction,the nonframework aluminum in hydrothermal pretreated samples including HZSM-5 and GaHZ-SM-5 is inserted into zeolites framework, that is to say realumination effect is in existence.
出处
《分析测试学报》
CAS
CSCD
1993年第6期1-5,共5页
Journal of Instrumental Analysis
基金
国家自然科学基金
关键词
HZSM-5
结构
热稳定性
铝
分子筛
^(27)AI MASNMR
HZSM-5
Realumination
Thermal stability of structure
