Key Laboratory of New Processing Technology for Nonferrous Metal & Materials, Ministry of Education, Guangxi Key Laboratory of Optical and Electronic Materials and Devices, Guilin University of Technology, Guilin 541004, China; Guangxi Key Laboratory of Green Chemical Materials and Safety Technology, Beibu Gulf University, Qinzhou 515000, China.
Guangxi Key Laboratory of Green Chemical Materials and Safety Technology, Beibu Gulf University, Qinzhou 515000, China.
Environ Res. 2024 Apr 15;247:118192. doi: 10.1016/j.envres.2024.118192. Epub 2024 Jan 14.
In this investigation, synthesis of a surface-functionalized chitosan known as amino-rich chitosan (ARCH) was achieved by successful modification of chitosan by polyethyleneimine (PEI). The synthesized ARCH was characterized by a specific surface area of 8.35 m g and a microporous structure, with pore sizes predominantly under 25 nm. The Zeta potential of ARCH maintained a strong positive charge across a wide pH range of 3-11. These characteristics contribute to its high adsorption efficiency in aqueous solutions, demonstrated by its application in removing various anionic dyes, including erioglaucine disodium salt (EDS), methyl orange (MO), amaranth (ART), tartrazine (TTZ), and hexavalent chromium ions (Cr(VI)). The adsorption capacities (Q) for these contaminants were measured at 1301.15 mg g for EDS, 1025.45 mg g for MO, 940.72 mg g for ART, 732.96 mg g for TTZ, and 350.15 mg g for Cr(VI). A significant observation was the rapid attainment of adsorption equilibrium, occurring within 10 min for ARCH. The adsorption behavior was well-described by the Pseudo-second-order and Langmuir models. Thermodynamic studies indicated that the adsorption process is spontaneous and endothermic in nature. Additionally, an increase in temperature was found to enhance the adsorption capacity of ARCH. The material demonstrated robust stability and selective adsorption capabilities in varied conditions, including different organic compounds, pH environments, sodium salt presence, and in the face of interfering ions. After five cycles of adsorption, ARCH maintained about 60% of its initial adsorption capacity. Due to its efficient adsorption performance, simple synthesis process, low biological toxicity, and cost-effectiveness, ARCH is a promising candidate for future water treatment technologies.
在这项研究中，通过成功地用聚乙烯亚胺（PEI）对壳聚糖进行修饰，合成了一种表面功能化的壳聚糖，即富含氨基的壳聚糖（ARCH）。合成的 ARCH 的比表面积为 8.35 m²/g，具有微孔结构，孔径主要小于 25nm。ARCH 的 Zeta 电位在 3-11 的宽 pH 范围内保持强烈的正电荷。这些特性使其在水溶液中具有高吸附效率，这一点在其应用于去除各种阴离子染料方面得到了证明，包括赤藓红酸钠（EDS）、甲基橙（MO）、苋菜红（ART）、柠檬黄（TTZ）和六价铬离子（Cr(VI)）。对这些污染物的吸附容量（Q）的测量值分别为 1301.15mg/g 对 EDS、1025.45mg/g 对 MO、940.72mg/g 对 ART、732.96mg/g 对 TTZ 和 350.15mg/g 对 Cr(VI)。一个显著的观察结果是，ARCH 可以在 10 分钟内快速达到吸附平衡。吸附行为可以很好地用伪二阶和朗格缪尔模型来描述。热力学研究表明，吸附过程是自发的，本质上是吸热的。此外，发现温度升高会增强 ARCH 的吸附能力。该材料在不同条件下表现出良好的稳定性和选择性吸附能力，包括不同的有机化合物、pH 环境、存在钠盐以及在干扰离子存在的情况下。在经过五次吸附循环后，ARCH 仍然保持了约 60%的初始吸附能力。由于其高效的吸附性能、简单的合成工艺、低生物毒性和成本效益，ARCH 是未来水处理技术的一个有前途的候选者。
