Fast Removal of Cr(VI) from Aqueous Solution Using Cr(VI)-Imprinted Polymer Particles

A novel Cr(VI) ion imprinted polymer (IIP) was proposed for fast removal of Cr(VI) from aqueous solution. 4-Vinylpyridine and N,N-diethylaminoethyl methacrylate were used as functional monomers, and ethylene glycol dimethacrylate and 2,2-azoisobisbutyronitrile were used as cross-linker and initiator in the presence of a binary porogenic solvent. The prepared Cr(VI)-IIPs were characterized by the Fourier transform infrared spectroscopy and scanning electron microscopy. The effects of pH, initial concentration of Cr(VI) in aqueous solution, temperature, and operating time on adsorption were investigated. At the low pH range of 1.5-2.5, the adsorption capacities were high. The influence of temperature was slight. The adsorption equilibrium time was within 3 min. The adsorption process followed the pseudo-second-order equation and the Langmuir isotherm model. The maximum adsorption capacity was up to 286.56 mg/g, and the selectivity factors of Cr(VI)/Cu(II), Cr(VI)/Cd(II), and Cr(VI)/Cr(III) were up to 135.78, 145.44, and 69.91, respectively.

提出了一种新型的铬（VI）离子印迹聚合物（IIP），用于从水溶液中快速去除铬（VI）。以4 - 乙烯基吡啶和甲基丙烯酸N,N - 二乙氨基乙酯作为功能单体，在二元致孔溶剂存在的情况下，以乙二醇二甲基丙烯酸酯和2,2 - 偶氮二异丁腈分别作为交联剂和引发剂。通过傅里叶变换红外光谱和扫描电子显微镜对制备的铬（VI） - IIPs进行了表征。研究了pH值、水溶液中铬（VI）的初始浓度、温度和操作时间对吸附的影响。在1.5 - 2.5的低pH范围内，吸附容量较高。温度的影响较小。吸附平衡时间在3分钟以内。吸附过程符合准二级方程和朗缪尔等温模型。最大吸附容量高达286.56毫克/克，铬（VI）/铜（II）、铬（VI）/镉（II）和铬（VI）/铬（III）的选择性系数分别高达135.78、145.44和69.91。