尉东光,周敬来,张碧江,八建明.焙烧对HZSM-5分子筛结构的影响[J].分子催化编辑部,1996,(6):
焙烧对HZSM-5分子筛结构的影响
The Influence of Calcination on the Structure of HZSM 5
  
DOI:
中文关键词:  
英文关键词:HZSM 5 Zeolite, Calcination, Dealumination, 29 Si, 27 Al MAS NMR
基金项目:
尉东光  周敬来  张碧江  八建明
中国科学院山西煤炭化学研究所,东京工业大学化学系
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中文摘要:
      运用魔角自转固态核磁共振谱(MAS-NMR),研究了焙烧对HZSM-5分子筛结构的影响.结果表明,高温焙烧将引起HZSM-5分子筛骨架的脱铝,当焙烧温度从500℃增加到700℃时,HZSM-5的骨架Si/Al比由16.7增加至22.7;而当焙烧温度由700℃到800℃时,骨架Si/Al比则由22.7增加到了48.5.27Al-MASNMR结果表明,从骨架上脱下来的铝,部分地形成了NMR不可见的无定形态.随着焙烧温度的升高,NMR不可见铝增多
英文摘要:
      The influence of calcination temperature (from 773 K to 1073 K) on the structure of HZSM 5 zeolite has been studied using 29 Si , 27 Al MAS NMR. It is found that calcination has caused partial dealumination of the framework of HZSM 5. From 773 K to 973 K, the framework Si/Al ratios of the zeolite change from 16.7 to 22.7. Furthermore, after calcination at 1073 K, the framework Si/Al ratio increases to 48.5. It suggests that the samples calcined at temperature higher than 973 K will suffer severe dealumination. 27 Al MAS NMR results imply that the Al out from HZSM 5 framework is only partially NMR visible. The NMR invisible Al increases with the increase of calcination temperature.
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