摘要
采用固体核磁共振、X射线衍射、红外吸收光谱和吡啶吸附红外光谱等分析方法,研究了磷改性对超稳Y分子筛的结构和表面性质的影响。结果表明:当磷含量较低时,磷改性主要在分子筛表面形成含端氧和端羟基的单聚态磷,使分子筛表面的强酸减少而弱酸增加;磷含量较高时,形成的主要产物是多聚态磷,分子筛表面的强酸和弱酸都会减少。分子筛经水热老化处理而形成的五配位超骨架铝,不易与单聚态磷反应,而易与多聚态磷发生作用,转化成四配位非骨架铝。
The influence of phosphate modification on the structure and surface property of uhrastable Y zeolites was investigated using different analytical methods such as MAS-NMR, XRD, FT-IR and pyridine-FT-IR. The results show that if the phosphate content is low, monomeric phosphate is mainly formed. It can reduce the amount of stronger acid and increase the amount of weaker acid on the surface of zeolite. When the phosphate content is high, polymeric phosphate comes into being and the amount of stronger acid and weaker acid obiviously decrease. After hydrothermal treatme is formed which can easily react with polymeric phosphate but not monomeric dral non-alumina is formed out of framework. nt, ph extraframework alumina osphate, so that tetrahe.
出处
《华东理工大学学报(自然科学版)》
EI
CAS
CSCD
北大核心
2006年第4期381-384,共4页
Journal of East China University of Science and Technology
基金
中国石油化工集团公司资助项目(103139)
关键词
超稳Y分子筛
磷
固体核磁共振
水热处理
ultrastable Y zeolite
phosphate
MAS-NMR
hydrothermal treatment