State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai 200237, PR China; Departamento de Química Orgánica, Universidad de Córdoba, Edif. Marie Curie, Ctra Nnal IV-A, Km 396, E14014 Córdoba, Spain.
State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai 200237, PR China.
J Hazard Mater. 2019 Feb 15;364:192-205. doi: 10.1016/j.jhazmat.2018.10.024. Epub 2018 Oct 15.
Many industrial wastewater streams contain heavy metals, posing serious and irreversible damage to humans and living organisms, even at low concentrations due to their high toxicity and persistence in the environment. In this study, high-performance monodispersed chitosan (CS) microspheres were prepared using a simple microfluidic method and evaluated for metal removal from contaminated water. Batch experiments were carried out to evaluate the adsorption characteristics for the removal of copper ions, one representative heavy metal, from aqueous solutions. The inherent advantages of microfluidics enabled a precise control of particle size (CV = 2.3%), while exhibiting outstanding selectivity towards target ions (adsorption capacity 75.52 mg g) and fair regeneration (re-adsorption efficiency 74% after 5 cycles). An integrated adsorption mechanism analytic system was developed based on different adsorption kinetics and isotherms models, providing an excellent adsorption prediction model with pseudo-second order kinetics (R = 0.999), while the isotherm was fitted best to the Langmuir model (R = 0.998). The multi-step adsorption process was revealed via quantitative measurements and schematically described. Selective adsorption performance of CS microspheres in the present of other competitive metal ions with different valence states has been demonstrated and studied by both experimental and density functional theory (DFT) analysis.
许多工业废水中含有重金属，由于其高毒性和在环境中的持久性，即使浓度很低，也会对人类和生物造成严重且不可逆转的损害。在这项研究中，使用简单的微流控方法制备了高性能单分散壳聚糖（CS）微球，并评估了其从受污染水中去除金属的性能。通过批量实验评估了从水溶液中去除铜离子（一种代表性重金属）的吸附特性。微流控技术的固有优势能够精确控制颗粒尺寸（CV=2.3%），同时对目标离子表现出出色的选择性（吸附容量为 75.52mg/g）和良好的再生能力（经过 5 次循环后，再吸附效率为 74%）。基于不同的吸附动力学和等温线模型，开发了集成的吸附机制分析系统，提供了一个出色的吸附预测模型，符合准二级动力学（R=0.999），而等温线最符合朗缪尔模型（R=0.998）。通过定量测量和示意性描述揭示了多步吸附过程。通过实验和密度泛函理论（DFT）分析研究了 CS 微球在存在具有不同价态的其他竞争金属离子时的选择性吸附性能。
