~1H-~(27)Al CP/MAS NMR STUDIES OF DEALUMINATED HZSM-5 ZEOLITE

• 出 处: Chinese Chemical Letters
• 发表日期: 1993年05期
• 关键词: coordinated zeolite coincidence probably aluminium treating immersed hydrotherma

Recently introduced method of ~1H-~(27)Al CP/MAS was used to study the dealuminated HZSM-5 zeolite. The experimental result suggests that the resonance signal at ca. 30ppm is an independent signal (not part of a second-order quadrupolar lineshape), probably resulted from 5-coordinated non-framework aluminium (Al~(NFP)). The coincidence of the peaks of 4-coordinated framework (Al~F) and 4-coordinated non-framework (Al~(NF)) aluminium at 60ppm was confirmed by ~(27)Al MAS NMR after treating the dealuminated sample with acetylacetone (acac).

Recently introduced method of ~ 1H- (27) Al CP / MAS was used to study the dealuminated HZSM-5 zeolite. The experimental result suggests that the resonance signal at ca. 30 ppm is an independent signal (not part of a second- order quadrupolar lineshape), probably resulted from 5-coordinated non-framework aluminum (Al ~ (NFP)). The coincidence of the peaks of 4-coordinated framework ) aluminum at 60 ppm was confirmed by (27) Al MAS NMR after treating the dealuminated sample with acetylacetone (acac).