Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, State Ministry of Education, Chongqing University, Chongqing 400045, PR China.
Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, State Ministry of Education, Chongqing University, Chongqing 400045, PR China.
Sci Total Environ. 2021 Mar 15;760:144307. doi: 10.1016/j.scitotenv.2020.144307. Epub 2020 Dec 8.
Developing robust and effective adsorbent for removing ubiquitous pharmaceutical diclofenac (DCF) from the aquatic environment is vitally important for environmental safety. Hence, a novel chitosan-based multilayer adsorbent (FCS-PD) with magnetic separation ability and surface functionality was successfully assembled, which had countless potential for removing contaminants from water. A series of instrumental technologies were performed to demonstrate the physicochemical properties of FCS-PD. Its adsorption performance toward DCF removal was comprehensively evaluated in synthetic water and surface water. The effects of microplastics, inorganic ions and humic acid on the adsorption were investigated. The maximum adsorption capacity of FCS-PD was calculated as 434.78 mg/g under neutral conditions, exhibiting superior adsorption performance than most reported adsorbents. The DCF in surface water was practically removed at low concentration (50 μg/L). FCS-PD presented a multistage kinetics controlled by chemisorption and intraparticle diffusion, which was emphasized by the pseudo-second-order kinetic and intra-particle diffusion analysis. After five cycles of adsorption and regeneration, the adsorption capacity only decreased by 9.9%, indicating the satisfactory regeneration of FCS-PD. The analysis of high-resolution X-ray photoelectron spectroscopic (XPS) and Fourier transform infrared spectroscopy (FTIR) revealed that the quaternary ammonium groups on the outer layer and the amino and hydroxyl groups on the chitosan layer are involved in the capture of DCF under electrostatic force and hydrogen bonding.
开发用于从水生环境中去除普遍存在的药物双氯芬酸 (DCF) 的稳健且有效的吸附剂对于环境安全至关重要。因此，成功组装了具有磁分离能力和表面功能的新型壳聚糖基多层吸附剂 (FCS-PD)，它具有从水中去除污染物的巨大潜力。一系列仪器技术用于证明 FCS-PD 的物理化学性质。在合成水和地表水全面评估了其对 DCF 去除的吸附性能。研究了微塑料、无机离子和腐殖酸对吸附的影响。在中性条件下，FCS-PD 的最大吸附容量计算为 434.78 mg/g，表现出比大多数报道的吸附剂更好的吸附性能。在低浓度 (50 μg/L) 下，实际去除了地表水中的 DCF。FCS-PD 呈现出由化学吸附和颗粒内扩散控制的多阶段动力学，这由伪二阶动力学和颗粒内扩散分析强调。经过五次吸附和再生循环，吸附容量仅下降了 9.9%，表明 FCS-PD 具有令人满意的再生能力。高分辨率 X 射线光电子能谱 (XPS) 和傅里叶变换红外光谱 (FTIR) 的分析表明，外层上的季铵基团和壳聚糖层上的氨基和羟基基团在静电力和氢键的作用下参与了 DCF 的捕获。
