吸水作用导致HZSM-5分子筛骨架重构的1H MAS NMR研究

• 作者: 丁大同 孙平川 王敬中 陈铁红 韩文慧
• 来源期刊: 中国学术期刊文摘
• 学科: 化学
• 关键词: 水 HZSM-5 沸石 1H 核磁共振
• 年，卷（期）: 2001,（2）
• 所属期刊栏目: 论文
• 页码范围: 219-220
• 页数: 2页
• 分类号: O647.33
• 语种: 中文

摘要

By 1H MAS NMR study, it was found that the cal cination did not directly cause dealumination in zeolite HZSM-5 if the sample i s not exposed to water. During the calcination, some of the Al-O bonds of the B ronsted acidic sites may be partially broken. When the calcined samples are expo sed in the moisture, the adsorbed water interacts with the partially broken bond and dealumination takes place. A proton signal at 2.7 ppm was found to be anoth er kind of adsorbed water besides the 6.5 ppm adsorbed water, which should be di fferentiated between the extra-framework aluminum hydroxyls.