Tianjin Key Laboratory of Aquatic Science and Technology, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China.
Tianjin Key Laboratory of Aquatic Science and Technology, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China.
Int J Biol Macromol. 2024 Oct;277(Pt 2):134046. doi: 10.1016/j.ijbiomac.2024.134046. Epub 2024 Jul 19.
In the present work, an environmentally-friendly, reusable hydrogel ball characterized by its great adsorption capacity to Cu(II) was synthesized. The preparation of this hydrogel drew on sodium alginate (SA) and carboxymethyl cellulose (CMC) as primary composition elements. The endeavor brought novelty by ingeniously infusing it with slurry magnesium hydroxide (MH). The factors (pH, SC-MH amount, initial concentration, adsorption time) that are critical to adsorption were also investigated. FTIR, SEM-EDS and XPS were used to reveal the adsorption mechanism of Cu on SC-MH. The results show that the surface of SC-MH is rough, and there are a large number of gully-like structures conducive to adsorption, which are rich in hydroxyl and carboxyl groups. Under the optimum conditions, the maximum adsorption capacity reached 215.68 mg/g. Based on its high R value (0.999), the Langmuir model is determined to be the most appropriate for describing the adsorption behavior, indicating monolayer homogeneous adsorption. The kinetic data align well with the pseudo-second-order kinetic model. Furthermore, thermodynamic analysis reveals the adsorption process to be spontaneous and endothermic, as demonstrated by a negative ΔG and positive ΔH (38.8859 KJ/mol). The mechanism involves electrostatic attraction, chelation, Mg(OH) adsorption and ion exchange.
在本工作中，合成了一种具有环境友好、可重复使用特点的水凝胶球，其对 Cu(II) 具有很强的吸附能力。该水凝胶的制备以海藻酸钠（SA）和羧甲基纤维素（CMC）为主要组成部分，巧妙地注入了浆状氢氧化镁（MH）。还研究了影响吸附的关键因素（pH、SC-MH 用量、初始浓度、吸附时间）。FTIR、SEM-EDS 和 XPS 用于揭示 Cu 在 SC-MH 上的吸附机理。结果表明，SC-MH 的表面粗糙，存在大量有利于吸附的沟壑状结构，富含羟基和羧基。在最佳条件下，最大吸附容量达到 215.68 mg/g。基于其高 R 值（0.999），确定 Langmuir 模型最适合描述吸附行为，表明单层均相吸附。动力学数据与拟二级动力学模型吻合较好。此外，热力学分析表明吸附过程是自发的和吸热的，由负 ΔG 和正 ΔH（38.8859 KJ/mol）证明。吸附机制涉及静电吸引、螯合、Mg(OH)吸附和离子交换。
