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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。
The pore structure properties of two series of Y zeolites prepared by a combination of chemical and hydrothermal methods were investigated by low temperature nitrogen adsorption. The results show that there are obvious differences in the pore structure formed by Y zeolite treated with different chemical reagents. However, when the Y-zeolite thus obtained is subjected to hydrothermal treatment and chemical treatment alternately under the same conditions, the pore structure shows a similar tendency of change, that is, the total specific surface area, the micropore specific surface area and the micropore volume first decrease and then increase , After the second hydrothermal and chemical treatment is once again declined again picked up. However, the “secondary pore” specific surface area produced during the process showed the opposite tendency of increasing and then decreasing first and then decreasing again. This trend may be related to the formation and disappearance of non-framework aluminum species in hydrothermal and chemical treatments.