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用干法制备高比表面ＡｌＦ３（Ｓ≥４５ｍ２／ｇ），对其表面酸性及酸中心类型进行了表征，并与其相结构进行了关联．对于由γ相及非晶相（二者总含量大于９５％）组成的ＡｌＦ３体系，ＮＨ３－ＴＰＤ曲线出现两个脱附峰，随着γ相含量的增加，弱酸强度变弱，强酸强度变强．脱附尾气滴定结果表明：随着γ相含量的升高，弱酸量和总酸量增加，强酸量则无显著变化，因而认为弱酸中心可能存在于ＡｌＦ３的γ相表面，强酸中心存在于其非晶相表面．吡啶吸附的红外光声光谱表明：ＡｌＦ３中既存在Ｌ酸中心，也存在Ｂ酸中心．氨气吸附的红外光谱结果表明：随着γ相含量的增加，Ｂ酸中心数量趋于减少．
High surface area AlF3 (S≥45m2 / g) was prepared by dry method. The surface acidity and acid sites were characterized and their structures were correlated. For the AlF3 system composed of γ phase and amorphous phase (the total content of the two is more than 95%), two desorption peaks appear on the NH3-TPD curve. As the γ phase content increases, the weak acid strength becomes weaker and the strong acid strength becomes stronger . The results of desorption tail gas titration showed that as the content of γ phase increased, the amount of weak acid and total acid increased, while the amount of strong acid did not change significantly. Therefore, it is considered that the weak acid center may exist on the γ phase of AlF3 and the strong acid center exists in its non- Crystal surface. Pyridine adsorption of infrared photoacoustic spectroscopy showed that: AlF3 in both L acid center, there are B acid center. The results of infrared spectroscopy of ammonia adsorption show that as the content of γ phase increases, the number of B acid centers tends to decrease.