Abstract:

The framework stability and surface acidity of zeolite β have been studied by infrared spectroscopy. The results show that the framework stability and surface acidity of H β zeolite depend on the experimental condition of template removal from the parent β zeolite. With thermal decomposition in vacuum at 450 ℃ and 550 ℃, the IR spectrum of H β exhibited exclusively two intense bands (3610 cm -1 and 3740 cm -1 )showing relatively ideal of its framework and high Bronsted acidity. If the template was burned off in air at 550 ℃,the 3610 cm -1 band of H β diminished considerably and two new IR bands (3780 cm -1 and 3670 cm -1 ) appeared, indicating the obvious framework dealumination. The later H β showed high Lewis acidity.

Key words: Zeolite β, Template removal, Framework stability