School of Resources and Environment, University of Jinan, Jinan 250022, China.
Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
J Colloid Interface Sci. 2018 Aug 1;523:56-64. doi: 10.1016/j.jcis.2018.03.080. Epub 2018 Mar 26.
EDTA modified β-cyclodextrin/chitosan (CDCS-EDTA) was fabricated successfully by a two-step method and applied to remove Pb(II) and anionic dye acid red 73 (AR). CDCS-EDTA was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and zeta potential analysis. The effects of experimental parameters including adsorbent dose, contact time and pH value on the adsorption efficiency of CDCS-EDTA for the pollutants were investigated. The maximum adsorption capacities were 114.8 mg g for Pb(II) and 754.6 mg g for AR under the optimal conditions. 93.4% of Pb(II) and 92.1% of AR could be adsorbed within 5 min, and the adsorptions reached equilibrium rapidly within 20 min and 10 min for Pb(II) and AR, respectively. A possible adsorption mechanism had been proposed that chelation of EDTA and electrostatic attraction of hydroxyl and amino groups dominated the adsorption of Pb(II), while the adsorption of AR mainly by the formation of inclusion complex with cyclodextrin cavities and electrostatic attraction with functional groups. For these two pollutants, the adsorption kinetic and isotherm data fitted well with the pseudo-second-order model and the Langmuir model, respectively. Thermodynamic studies implied that the adsorption process of Pb(II) and AR were spontaneous. Furthermore, the excellent regeneration performance indicated that CDCS-EDTA has a promising application in water treatment.
EDTA 修饰的β-环糊精/壳聚糖（CDCS-EDTA）通过两步法成功制备，并应用于去除 Pb(II)和阴离子染料酸性红 73（AR）。通过扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）和 zeta 电位分析对 CDCS-EDTA 进行了表征。考察了吸附剂用量、接触时间和 pH 值等实验参数对 CDCS-EDTA 去除污染物效率的影响。在最佳条件下，CDCS-EDTA 对 Pb(II)和 AR 的最大吸附容量分别为 114.8 mg/g 和 754.6 mg/g。Pb(II)和 AR 的吸附分别在 5 min 内达到 93.4%和 92.1%，吸附在 20 min 和 10 min 内迅速达到平衡。提出了一种可能的吸附机制，即 EDTA 的螯合作用和羟基和氨基的静电吸引主导了 Pb(II)的吸附，而 AR 的吸附主要是通过与环糊精空腔形成包合络合物和与官能团的静电吸引来实现的。对于这两种污染物，吸附动力学和等温线数据分别很好地符合准二级模型和朗缪尔模型。热力学研究表明，Pb(II)和 AR 的吸附过程是自发的。此外，优异的再生性能表明 CDCS-EDTA 在水处理中有很好的应用前景。
