Politecnico di Torino, Department of Applied Science and Technology, Corso Duca degli Abruzzi 24, 10129 Torino, Italy.
CNR-ISMAC, Institute for Macromolecular Studies, Corso Pella 16, 13900 Biella, Italy.
Carbohydr Polym. 2014 Sep 22;110:367-73. doi: 10.1016/j.carbpol.2014.04.016. Epub 2014 Apr 18.
A chitosan-coated cotton gauze was prepared by UV-curing and tested as adsorbent to remove copper (II) and chromium (VI) ions from water solutions. The adsorbent characterization was carried out by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX) and Fourier Transform Infrared Spectroscopy in Attenuated Total Reflection (FTIR-ATR). Adsorption of copper and chromium ions onto the gauze was tested in batch process at different experimental conditions. The effects of pH, temperature, contact time and metal ion concentration were investigated. The optimum adsorption took place at pH 3 for Cr(VI) and pH 5 for Cu(II) ions respectively, while the temperature did not affect the adsorption process. Pseudo-first and pseudo-second order models were used to investigate the adsorption kinetics which was found very fast and better described by the pseudo-second order model for both metal ions. The adsorption of Cr(VI) ions was satisfactory described by the Langmuir isotherm, while that of Cu(II) ions showed a better agreement with the Freundlich model.
一种壳聚糖涂层棉纱布通过紫外光固化制备,并被测试为吸附剂,以从水溶液中去除铜(II)和铬(VI)离子。通过扫描电子显微镜(SEM)、能量色散 X 射线能谱(EDX)和衰减全反射傅里叶变换红外光谱(FTIR-ATR)对吸附剂进行了表征。在不同的实验条件下,采用批量法测试了铜和铬离子在纱布上的吸附情况。考察了 pH 值、温度、接触时间和金属离子浓度的影响。对于 Cr(VI),最佳吸附发生在 pH 3,对于 Cu(II)离子,最佳吸附发生在 pH 5,而温度对吸附过程没有影响。采用拟一级和拟二级动力学模型研究了吸附动力学,结果表明,两种金属离子的吸附过程都非常快,且更符合拟二级动力学模型。Cr(VI)离子的吸附可以很好地用朗缪尔等温线描述,而 Cu(II)离子的吸附则与 Freundlich 模型更吻合。