物理化学学报 >> 1992, Vol. 8 >> Issue (05): 613-618.doi: 10.3866/PKU.WHXB19920508

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高硅Y沸石“二次孔”结构的物理吸附法研究

裴站芬; 刘兴云; 李宣文   

  1. 北京大学化学系，北京 100871
  • 收稿日期:1991-05-09 修回日期:1991-12-09 发布日期:1992-10-15
  • 通讯作者: 裴站芬

The Studies of Pore Structures of High-Silica Y Zeolites by N2 Adsorption

Pei Zhan-Fen; Liu Xing-Yun; Li Xuan-Wen   

  1. Department of Chemistry, Peking University, Beijing 100871
  • Received:1991-05-09 Revised:1991-12-09 Published:1992-10-15
  • Contact: Pei Zhan-Fen

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摘要： 用低温氮物理吸附法研究了化学法和水热法相结合制备的两个系列Y沸石的孔结构性质。研究结果表明, 用不同化学试剂处理Y沸石形成的孔结构有明显差别。但是, 当把由此得到的Y沸石在相同条件下交替进行水热处理和化学处理时, 孔结构却呈现类似的变化趋势, 即总比表面积、微孔比表面积和微孔体积是先下降后上升, 经第二次水热和化学处理是再次下降再次回升。而过程中产生的“二次孔”比表面积却呈现先上升后下降, 又回升又下降的相反的变化趋势。这种变化趋势, 可能与水热处理和化学处理过程中非骨架铝物种的形成与消失有关。

关键词: Y沸石, 改性, 氮吸附, 孔结构, 二次孔体系

Abstract: The properties of pore structure of high-silica Y zeolites prepared by combined hydrothermal-chemical treatments have been characterized by measuring N_2 adsorption-desorption isotherms at 77.4 K. The surface area and micropore volume for the sam-ples have been calculated by means of t-method and MP method. It has been found that two zeolites Y samples dealuminated by different chemical agents have apparent differences in their pore structures. But, when these two samples are further submitted to hydrothermal treatments combined chemical treatments, an evolution with similar tendencies in pore structure has been observed, namely, their total surface area, the surface area of micropores and micropore volume have reduced after hydrothermal treatments and increased after chemical treatments. On the contrary, the surface area of the secondary pore systems has been increased after hydrothermal treatments and reduced after chemical treatments. This evolution of pore structure may be related to the formation and elimination of non-framework aluminium species.

Key words: Zeolite Y, Mordification, N2 adsorption, Pore structure, Secondary pore system