Gong Zhiyang, Zhao Miaomiao, Ma Degang, Sun Zeying, Hu Junjie
Environmental Science and Engineering, Tianjin University, Tianjin 300350, PR China.
Environmental Science and Engineering, Tianjin University, Tianjin 300350, PR China.
Int J Biol Macromol. 2025 May;306(Pt 2):141498. doi: 10.1016/j.ijbiomac.2025.141498. Epub 2025 Feb 25.
To address Cd(II) contamination in aquatic environments and the limitations of conventional adsorbents, such as poor mechanical strength, low adsorption capacity, and insufficient reusability, a novel hydrogel bead adsorbent with a semi-interpenetrating polymer network (semi-IPN) was developed using a simple physical and chemical crosslinking approach. The hydrogel beads, composed of poly(acrylamide-co-2-acrylamido-2-methylpropanesulfonic acid)-carboxymethyl cellulose-Ca(II) (P(AM-AMPS)-CMC-Ca(II)), exhibited a high compressive strength of 60.0 kPa. Their well-developed porous structure and abundant functional groups significantly enhanced their Cd(II) adsorption potential. Isothermal, kinetic, and thermodynamic adsorption experiments conducted at pH 5.65 indicated that Cd(II) adsorption onto the hydrogel beads followed the Freundlich isotherm model and the pseudo-second-order kinetic model, suggesting a non-spontaneous, endothermic, and heterogeneous multilayer adsorption process. The adsorption mechanism was governed by both physical and chemical interactions, with a maximum adsorption capacity of 275.13 mg/g. Characterization (SEM, FTIR, XPS) confirmed that Cd(II) adsorption was primarily driven by electrostatic attraction, complexation with functional groups, and ion exchange. After five adsorption-desorption cycles using 0.1 mol/L HCl as the desorption agent, the adsorption efficiency remained above 90 %. Overall, the hydrogel beads, with simple preparation method, high strength, and excellent regeneration, could be a promising eco-friendly adsorbent for Cd(II) removal.
为了解决水生环境中的镉（II）污染问题以及传统吸附剂存在的局限性，如机械强度差、吸附容量低和可重复使用性不足等，采用简单的物理和化学交联方法制备了一种具有半互穿聚合物网络（semi-IPN）的新型水凝胶珠吸附剂。由聚（丙烯酰胺 - 共 - 2 - 丙烯酰胺基 - 2 - 甲基丙烷磺酸） - 羧甲基纤维素 - 钙（II）（P（AM - AMPS） - CMC - Ca（II））组成的水凝胶珠表现出60.0 kPa的高抗压强度。其发达的多孔结构和丰富的官能团显著增强了它们对镉（II）的吸附潜力。在pH 5.65下进行的等温、动力学和热力学吸附实验表明，水凝胶珠对镉（II）的吸附遵循Freundlich等温模型和准二级动力学模型，表明这是一个非自发、吸热且非均相的多层吸附过程。吸附机制受物理和化学相互作用的共同控制，最大吸附容量为275.13 mg/g。表征（SEM、FTIR、XPS）证实，镉（II）的吸附主要由静电吸引、与官能团的络合以及离子交换驱动。使用0.1 mol/L HCl作为解吸剂进行五次吸附 - 解吸循环后，吸附效率仍保持在90%以上。总体而言，这种制备方法简单、强度高且再生性能优异的水凝胶珠有望成为一种用于去除镉（II）的环保型吸附剂。
