Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Environ Sci Pollut Res Int. 2018 Apr;25(11):11045-11053. doi: 10.1007/s11356-018-1355-1. Epub 2018 Feb 6.
A novel quaternary ammonium polyethylene nonwoven fabric for removing chromium ions from water was prepared via radiation-induced grafting of glycidyl methacrylate and further modification with N,N'-dimethylethylenediamine. The structural and morphological characteristics of the adsorbent were analyzed using Fourier transform infrared spectroscopy (FTIR), thermogravimetry and differential thermogravimetry (TG/DTG), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The influences of several principal factors, including pH value, initial Cr(VI) concentration, contact time, and coexisting anions (including SO, CO, NO, PO, and Cl), on adsorption performance were investigated via batch tests. The results showed that the optimum removal efficiency was 99.2% at pH 3 and the maximum adsorption quantity for Cr(VI) at 25 °C was 336 mg/g. The adsorption kinetic parameters were better fitted with the pseudo-second-order kinetic model, and the equilibrium data were described very well by the Freundlich isotherm model. Furthermore, the as-synthesized adsorbent exhibited excellent regeneration and recyclability while maintaining high adsorption performance after five adsorption/desorption cycles.
一种新型的季铵盐聚乙烯无纺布，通过辐射引发甲基丙烯酸缩水甘油酯接枝，然后用 N,N'-二甲基乙二胺进一步修饰，用于从水中去除铬离子。使用傅里叶变换红外光谱（FTIR）、热重分析和差示热重分析（TG/DTG）、扫描电子显微镜（SEM）和 X 射线光电子能谱（XPS）对吸附剂的结构和形态特征进行了分析。通过批量试验研究了几个主要因素，包括 pH 值、初始 Cr(VI)浓度、接触时间和共存阴离子（包括 SO、CO、NO、PO 和 Cl）对吸附性能的影响。结果表明，在 pH 3 时最佳去除效率为 99.2%，在 25°C 时 Cr(VI)的最大吸附量为 336mg/g。吸附动力学参数更符合准二级动力学模型，平衡数据很好地符合 Freundlich 等温线模型。此外，合成的吸附剂在经过五次吸附/解吸循环后，仍保持较高的吸附性能，具有良好的再生和可循环利用性。
