不同比例侧基的两个系列MIL-101(Cr)类化合物的合成及其吸附性能研究

The synthesis and adsorption properties of two serials MIL-101(Cr)compounds with different proportional pendant groups

采用水热法以不同配比的2-磺酸基对苯二甲酸单钠(或2-胺基对苯二甲酸)、对苯二甲酸、三氧化铬为原料合成了两系列共10个MIL-101(Cr)类化合物.采用X射线粉末衍射仪、傅里叶变换红外光谱仪、物理吸附仪等手段测定了这些化合物性质.比表面积测定研究结果表明:对于MIL-101(Cr)-SO3H系列化合物,当2-磺酸基对苯二甲酸单钠和对苯二甲酸摩尔比1∶3时,BET比表面积为3011 m2/g(Langmuir比表面积为4420 m2/g),孔容为1.634m3/g,达到该系列最大;对于MIL-101(Cr)-NH2系列化合物,当2-胺基对苯二甲酸和对苯二甲酸摩尔比3∶1时,BET比表面积为1752 m2/g(Langmuir比表面积为2526 m2/g),孔容为0.8724m3/g,达到该系列最大.比较这两个系列的吸附性能,引入胺基基团不利于MIL-101(Cr)材料吸附性能的提高.

Two series of MIL-101 （Cr） compounds were synthesized by hydrothermal method with different ratios of 2-sulfoterephthalic acids （or 2-aminoterephthalie acids）, benzene-l,4-dicarboxylic acids and chromium trioxide. The properties of these compounds were determined by powder X-ray diffraction （XRD）, fouriertransform infrared spectroscopy, and nitrogen physical adsorption. The results of the specific surface area measurements have shown that for the series of MIL-101 （Cr）-SO3H compounds, when the mol ratio of 2-sulfoterephthalic acid to benzene-l, 4-dicarboxylic acid is 1：3, the specific surlhce area of BET is 3011 m2/g（the specific surface area of Langmuir is 4420m2/g）, the pore volume is 1.634cm3/g, to the maximum. For the series of MIL-101（Cr）-NH2 compounds, when tool ratio of 2-aminoterephthalie acid to benzene-l,4-di- carboxylic acid is 3：1, the specific surface area of BET is 1752m2/g（the specific surface area of Langmuir is 2526m2/g）, the pore volume is 0.8724 m3/g, reaching the maximum in this series. Therefore, comparing the adsorption properties of these two series, it can conclude that the introduction of amino groups is not con- dueive to the improvement of material adsorption performance.