稀土金属有机骨架材料对染料的吸附性能研究

Study on adsorption property of rare-earth metal-organic framework material on dye

以均苯三甲酸和六水合硝酸钇(Ⅲ)为原料,合成了一种稀土金属有机骨架材料Y(BTC)(H2O)(Y-BTC)。通过XRD对材料的物相进行表征,并采用紫外可见分光光度计研究了刚果红的初始浓度、吸附作用时间、溶液pH、背景离子和Y(BTC)(H2O)活化等因素对其吸附性能的影响。结果表明,Y(BTC)(H2O)对刚果红的吸附量随着刚果红初始浓度的增加而逐渐增大,并且酸性溶液和活化有利于Y(BTC)(H2O)对刚果红的吸附。K+、Na+、Li+3种背景离子的存在不利于Y(BTC)(H2O)对刚果红溶液的吸附,这是由于它们会与刚果红抢占Y(BTC)(H2O)上的吸附位点,并占据Y(BTC)(H2O)孔道而减少Y(BTC)(H2O)与刚果红的接触机会。Y(BTC)(H2O)对刚果红的吸附过程符合Freundlich等温吸附模型和准二级动力学模型。

A rare-earth metal-organic framework material Y(BTC)(H2O)(Y-BTC)was synthesized by benzene-1,3,5-tricarboxylic acid and yttrium(Ⅲ)nitrate hexahydrate as raw materials.The phase of the Y(BTC)(H2O)was characterized by XRD.The effect of initial concentration of congo red,adsorption time,the solution pH,background ions,Y(BTC)(H2O)activation on adsorption performance were studied by using UV-visible spectrophotometer.The results shown that the adsorption capacity of Y(BTC)(H2O)increased with increasing the initial concentration of congo red.Acid solution and activation were beneficial to adsorption of congo red by Y(BTC)(H2O).The adsorption amount of Y(BTC)(H2O)on congo red decreased with the addition of background ions Li+,K+ and Na+.The presence of K+,Na+ and Li+ background ions was not conducive to the adsorption of Y(BTC)(H2O)on congo red.This was because they seized the adsorption site of Y(BTC)(H2O)and occupied the pore passage of Y(BTC)(H2O)with congo red,thus reduced the contact opportunities between Y(BTC)(H2O)and congo red.