固态MAS NMR研究Bronsted酸部位在石H-Mordenite中的固态MAS NMR研究
Hua Huo1, Luming Peng, Zhehong Gan
1Department of Chemistry, State University of New York at Stony Brook, Stony Brook, New York 11794-3400, USA.
Journal of the American Chemical Society
|May 5, 2012
概括
研究人员使用先进的NMR技术在H-Mordenite热岩中绘制布伦斯特德酸位点的地图. 这项研究揭示了不同的酸位点位置和可访问性,这对于理解热带石催化是至关重要的.
科学领域:
- 固态NMR光谱学 固态NMR光谱学
- 材料化学 材料化学
- 催化剂是一种催化剂.
背景情况:
- 热石,特别是H-Mordenite (H-MOR),是重要的工业催化剂.
- 了解布伦斯特酸位点的确切位置和性质是优化其性能的关键.
- 之前的方法缺乏足够的分辨率来充分描述H-MOR.内的多种酸性位点.
研究的目的:
- 为了阐明 H-Mordenite 中 Brønsted 酸位点的局部结构和分布.
- 根据它们的OH距离来区分布伦斯特德酸位.
- 量化这些酸性部位的可访问性,以探测分子.
主要方法:
- 使用了 (17) O-(1) H双共振NMR光谱学.
- 采用了交叉极化魔法角度旋转 (CPMAS) 的核磁共振,CP旋转回声双共振 (CP-REDOR) 的核磁共振和异质核相关性 (HETCOR) 的核磁共振.
- 使用trimethylphosphine吸附量化的网站可访问性.
主要成果:
- 使用不同的NMR技术和接触时间,具有不同O-H距离的突出布伦斯特德酸位点.
- 建议在H-Mordenite框架内为不同类型的布伦斯特德酸现场提供特定位置.
- 确定了各种布伦斯特德酸站点的可访问性.
结论:
- 该研究成功地绘制了H-Mordenite中的多种 Brønsted 酸位点.
- 核磁共振光谱学,特别是 (17) O-(1) H双共振,是有效的特征部位.
- (17) 化学转移相关性有助于在地石研究的地点分配.
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