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用2500型自动吸附仪测定了结晶度在8～80%间的9个ZSM-5沸石分子筛的低温氮吸附等温线,并用修正三参数BET方程关联,应用常数C值选择了用于微孔结构分析的标准等温线.用V-n作图法获得了样品的主要孔结构参数.获得的平均微孔尺寸在6.2～7.8?之间,与ZSM-5分子筛晶体的孔道尺寸5.5～9.0?完全一致.用获得的主要孔结构参数与结晶度数据进行了形如C%=a+bm的线性关联,用于关联的参数有:微孔表面积和体积,BET表面积,三参数BET表面积和Langmiur表面积.关联系数在0.990～O.995之间,标准偏差在2.77～3.20个结晶度单位之间.对未知样品的计算结果与X-射线结果间的比较说明,微孔体积和表面积关联较其它三个为好.经验关联为用吸附测量估算结晶度数据提供了可能.最后对影响计算结果的若干因素作了讨论.
The low temperature nitrogen adsorption isotherms of nine ZSM-5 zeolites with crystallinity between 8% and 80% were determined with a 2500 auto-adsorbent and correlated with a modified three-parameter BET equation using a constant C value for the microporous structure The main pore parameters of the samples were obtained by Vn mapping.The average pore size obtained was between 6.2 and 7.8 μm, which was completely consistent with the pore size of ZSM-5 zeolite crystals from 5.5 to 9.0 μm. A linear correlation, such as C% = a + bm, was obtained using the obtained main pore structure and crystallinity data for the associated parameters: micropore surface area and volume, BET surface area, BET surface area by three parameters and Langmiur surface area. The coefficients range from 0.990 to 0.955 and the standard deviations range from 2.77 to 3.20 Crystallinity units.The comparison between the calculated results and the X-ray results for unknown samples shows that the correlation between micropore volume and surface area is better than the other three Good. Empirical correlations allow the estimation of crystallinity data using adsorption measurements. Finally, several factors that affect the calculation results are discussed.