Zhongyuan Critical Metals Laboratory, Zhengzhou University, Zhengzhou 450001, China.
School of Chemical Engineering, Zhengzhou University, Zhengzhou 450001, China.
Molecules. 2023 Mar 2;28(5):2307. doi: 10.3390/molecules28052307.
Chitosan (CS) is a natural and low-cost adsorbent for capturing metal ions and organic compounds. However, the high solubility of CS in acidic solution would make it difficult to recycle the adsorbent from the liquid phase. In this study, the CS/FeO was prepared via FeO nanoparticles immobilized onto a CS surface, and the DCS/FeO-Cu was further fabricated after surface modification and the adsorption of Cu ions. The meticulously tailored material displayed the sub-micron size of an agglomerated structure with numerous magnetic FeO nanoparticles. During the adsorption of methyl orange (MO), the DCS/FeO-Cu delivered a superior removal efficiency of 96.4% at 40 min, which is more than twice the removal efficiency of 38.7% for pristine CS/FeO. At an initial MO concentration of 100 mg L, the DCS/FeO-Cu exhibited the maximum adsorption capacity of 144.60 mg g. The experimental data were well explained by the pseudo-second-order model and Langmuir isotherm, suggesting the dominant monolayer adsorption. The composite adsorbent still maintained a large removal rate of 93.5% after five regeneration cycles. This work develops an effective strategy to simultaneously achieve high adsorption performance and convenient recyclability for wastewater treatment.
壳聚糖（CS）是一种天然且低成本的吸附剂，可用于捕获金属离子和有机化合物。然而，CS 在酸性溶液中的高溶解度使得从液相中回收吸附剂变得困难。在这项研究中，通过将 FeO 纳米颗粒固定在 CS 表面上制备了 CS/FeO，然后经过表面改性和 Cu 离子吸附制备了 DCS/FeO-Cu。精心设计的材料显示出亚微米尺寸的团聚结构，其中含有大量磁性 FeO 纳米颗粒。在吸附甲基橙（MO）时，DCS/FeO-Cu 在 40 分钟内达到了 96.4%的优异去除效率，是原始 CS/FeO 的去除效率 38.7%的两倍多。在初始 MO 浓度为 100mg/L 时，DCS/FeO-Cu 表现出 144.60mg/g 的最大吸附容量。实验数据很好地解释了伪二级模型和 Langmuir 等温线，表明吸附主要是单层吸附。该复合吸附剂在经过五次再生循环后仍保持 93.5%的高去除率。这项工作开发了一种有效的策略，可同时实现废水处理的高吸附性能和方便的可回收性。
