Y分子筛改性对其结构和酸性的影响  

Effects of modification methods on structure and acidic property of Y zeolite

作　　者：程时文[1] 兰玲 于彦校[1] 袁晓亮 金君素[1] 吴平易 

机构地区：[1]北京化工大学化学工程学院,北京100029 [2]中国石油石油化工研究院,北京100195

出　　处：《石化技术与应用》2011年第5期401-405,共5页Petrochemical Technology & Application

基　　金：中国石油石油化工研究院资助基金项目(项目名称:多产乙烯原料的加氢裂化催化材料研究;项目编号:09-YK-05-07)

摘　　要：采用铵交换、水热处理、水热-草酸处理的方法对Y分子筛进行改性,考察了改性方法对Y分子筛的硅铝比、相对结晶度、晶胞常数、比表面积、孔结构、骨架振动及酸性的影响。结果表明,随着改性程度的加深,Y分子筛的体相和骨架硅铝比均增大,晶胞常数由2.463 0 nm降至2.446 2 nm,并可保持较高的相对结晶度;水热处理后产生大量的非骨架铝,再经草酸处理可有效脱除所产生的非骨架铝,表现出更高的比表面和二次孔孔容;总酸量下降,中强酸酸量增大;水热处理后强L酸量增加,草酸改性则可以提高B酸量。Y zeolites were modified by different isomorphous substitution methods,including ammoni- um ion exchange,hydrothermal treatment and hydrothermaloxalic acid treatment. The effects of modification methods on the Si/A1 molar ratio, relative crystallinity, unit cell constant, specific surface area, pore structure, skeletal vibration and acidic property were investigated. The results showed that with deepening modification,the Si/A1 mole ratio increased in bulk phase and framework of Y zeolite,the unit cell constant （ a0 ） decreased from 2. 463 0 nm to 2.446 2 nm and the modified Y zeolite retained higher relative crystallinity. The hydrothermal treatment led to a large quantity of non -framework aluminum could be effectively removed by oxalic acid treatment, which showing higher specific surface area and secondary pore volume. The total acidity decreased and the mediately strong acid increased. The hydrothermal treatment could enhance strong Lewis acidity and the oxalic acid treatment the Brφnsted acid.

关 键 词：分子筛 Y分子筛 铵离子交换 水热处理 草酸 酸性 晶胞常数 孔容 

分 类 号：TE624.95[石油与天然气工程—油气加工工程]