College of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
J Hazard Mater. 2011 Oct 30;194:193-201. doi: 10.1016/j.jhazmat.2011.07.080. Epub 2011 Aug 6.
A novel, thiourea-chitosan coating on the surface of magnetite (Fe(3)O(4)) (Ag-TCM) was successfully synthesized using Ag(I) as imprinted ions for adsorption and removal of Ag(I) ions from aqueous solutions. The thermal stability, chemical structure and magnetic property of the Ag-TCM were characterized by the scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR) and vibrating sample magnetometer (VSM), respectively. Batch adsorption experiments were performed to evaluate the adsorption conditions, selectivity and reusability. The results showed that the maximum adsorption capacity was 4.93 mmol/g, observed at pH 5 and temperature 30°C. Equilibrium adsorption was achieved within 50 min. The kinetic data, obtained at the optimum pH 5, could be fitted with a pseudo-second order equation. Adsorption process could be well described by Langmuir adsorption isotherms and the maximum adsorption capacity calculated from Langmuir equation was 5.29 mmol/g. The selectivity coefficient of Ag(I) ions and other metal cations onto Ag-TCM indicated an overall preference for Ag(I) ions, which was much higher than non-imprinted thiourea-chitosan beads. Moreover, the sorbent was stable and easily recovered, the adsorption capacity was about 90% of the initial saturation adsorption capacity after being used five times.
一种新型的、表面覆盖硫脲壳聚糖的磁铁矿（Fe(3)O(4)）（Ag-TCM）通过使用 Ag(I) 作为印迹离子成功合成，用于从水溶液中吸附和去除 Ag(I)离子。通过扫描电子显微镜（SEM）、傅里叶变换红外光谱仪（FT-IR）和振动样品磁强计（VSM）分别对 Ag-TCM 的热稳定性、化学结构和磁性进行了表征。通过批量吸附实验评估了吸附条件、选择性和可重复使用性。结果表明，在 pH 值为 5 和温度为 30°C 时，最大吸附容量为 4.93mmol/g。在 50 分钟内达到平衡吸附。在最佳 pH 值 5 下获得的动力学数据可以用伪二阶方程拟合。吸附过程可以很好地用 Langmuir 吸附等温线描述，从 Langmuir 方程计算出的最大吸附容量为 5.29mmol/g。Ag-TCM 对 Ag(I)离子和其他金属阳离子的选择性系数表明，Ag-TCM 对 Ag(I)离子具有总体偏好，远高于非印迹硫脲壳聚糖珠。此外，该吸附剂稳定且易于回收，使用五次后吸附容量约为初始饱和吸附容量的 90%。
