Thuan Le Van, Chau Tran Bao, Ngan Tran Thi Kieu, Vu Tran Xuan, Nguyen Dinh Duc, Nguyen Minh-Hiep, Thao Dang Thi Thanh, To Hoai Nguyen, Sinh Le Hoang
a Center for Advanced Chemistry, Institute of Research & Development , Duy Tan University , Danang , Vietnam.
b Faculty of Environment , Duy Tan University , Danang , Vietnam.
Environ Technol. 2018 Jul;39(14):1745-1752. doi: 10.1080/09593330.2017.1337236. Epub 2017 Jun 13.
In this study, a new method for preparation of cross-linked magnetic chitosan particles (MCPs) from steel slag and shrimp shells using green tea extract as crosslinking reagent has been presented. The MCPs obtained were characterized by means of X-ray diffraction analysis, Fourier-transform infrared spectroscopy, scanning electron microscopy and magnetic properties, and then were used to investigate the adsorption properties of Cu(II) and Ni(II) ions in aqueous solutions. The influence of experimental conditions such as contact time, pH value, adsorbent dose and initial metal concentration, and the possibility of regeneration were studied systematically. The Cu(II) and Ni(II) adsorption isotherms, kinetics and thermodynamics have been measured and discussed. The results show that the synthesized MCPs have high adsorption capacity for both metal ions (126.58 mg/g for Cu(II) and 66.23 mg/g for Ni(II)), and have excellent regeneration stability with efficiency of greater than 83% after five cycles of the adsorption-regeneration process. The adsorption process of Ni(II) and Cu(II) on MCPs was feasible, spontaneous and exothermic, and better described by the Langmuir model and pseudo-second-order kinetic equation. The MCPs can be applied as a low cost and highly efficient adsorbent for removal of heavy metals from wastewater due to its high adsorption capacity, easy recovery and good reusability.
在本研究中，提出了一种以绿茶提取物为交联剂，由钢渣和虾壳制备交联磁性壳聚糖颗粒（MCPs）的新方法。对所得的MCPs进行了X射线衍射分析、傅里叶变换红外光谱、扫描电子显微镜和磁性表征，然后用于研究其对水溶液中Cu(II)和Ni(II)离子的吸附性能。系统研究了接触时间、pH值、吸附剂用量和初始金属浓度等实验条件的影响以及再生的可能性。测定并讨论了Cu(II)和Ni(II)的吸附等温线、动力学和热力学。结果表明，合成的MCPs对两种金属离子均具有较高的吸附容量（对Cu(II)为126.58 mg/g，对Ni(II)为66.23 mg/g），并且在吸附-再生过程进行五个循环后具有优异的再生稳定性，效率大于83%。Ni(II)和Cu(II)在MCPs上的吸附过程是可行的、自发的且放热的，并且用Langmuir模型和准二级动力学方程能更好地描述。由于MCPs具有高吸附容量、易于回收和良好的可重复使用性，因此可作为一种低成本、高效的吸附剂用于去除废水中的重金属。
