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运用魔角自转固态核磁共振谱（ＭＡＳ－ＮＭＲ），研究了焙烧对ＨＺＳＭ－５分子筛结构的影响．结果表明，高温焙烧将引起ＨＺＳＭ－５分子筛骨架的脱铝，当焙烧温度从５００℃增加到７００℃时，ＨＺＳＭ－５的骨架Ｓｉ／Ａｌ比由１６．７增加至２２．７；而当焙烧温度由７００℃到８００℃时，骨架Ｓｉ／Ａｌ比则由２２．７增加到了４８．５．２７Ａｌ－ＭＡＳＮＭＲ结果表明，从骨架上脱下来的铝，部分地形成了ＮＭＲ不可见的无定形态．随着焙烧温度的升高，ＮＭＲ不可见铝增多
The effect of calcination on the structure of HZSM-5 zeolite was investigated by using magic angle rotation solid state nuclear magnetic resonance spectroscopy (MAS-NMR). The results show that the high temperature calcination will cause the dealumination of HZSM-5 zeolite framework. When the calcination temperature increases from 500 ℃ to 700 ℃, the framework Si / Al ratio of HZSM-5 increases from 16.7 to 22.7. The Si / Al ratio increases from 22.7 to 48.5.27 Al-MAS NMR at temperatures ranging from 700 ° C to 800 ° C. The results show that the aluminum removed from the framework partially forms an invisible amorphous state of NMR . As the calcination temperature increases, the NMR invisible aluminum increases