Aluminum in mesoporous silica-alumina

作者：Parker Wallace O'Neil Jr^*; Wegner Sebastian

来源：Microporous and Mesoporous Materials, 2012, 158: 235-240.

DOI：10.1016/j.micromeso.2012.03.050

• Al-27 MAS NMR spectroscopy
• Mesoporous silica-alumina
• Aluminum coordination
• Anisotropic parameter distribution

Quantitative Al-27 MAS NMR spectral decomposition, employing a Gaussian distribution of anisotropic parameters, along with triple-quantum spectroscopy were used to examine the aluminum nuclei in mesoporous silica-alumina (MSA). Only half of the Al nuclei in H-MSA were detected by MAS NMR analysis at 7 Tesla field strength. Complete hydration provided full detection and revealed large amounts of AlO6 sites (ca. 40% mole). All these sites were converted to AlO4 sites, with NH3 protonation, using a pressurized ammonia-water treatment. Al-27 and Si-29 MAS NMR spectral changes indicated this occurred by partial reformation of the aluminosilicate.

• 出版日期2012-8-1