College of Chemistry and Chemical Engineering, and Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese Resources, Central South University, Changsha, 410083, Hunan, China.
College of Chemistry and Chemical Engineering, and Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese Resources, Central South University, Changsha, 410083, Hunan, China.
J Environ Manage. 2022 Apr 15;308:114631. doi: 10.1016/j.jenvman.2022.114631. Epub 2022 Feb 5.
Heavy metal wastewater pollution has become an ecological challenge worldwide. This study reports the development of a novel poly (6-acryloylamino-N-hydroxyhexanamide) (PAHHA) resin for effective adsorption of heavy metal ions, including Cu, Pb and Ni. The chelating resin was synthesized by the grafting reaction between 6-amino-N-hydroxyhexanamide and polyacrylic resin, thus containing the hydroxamate and acylamino groups. The batch adsorption experiments revealed that the PAHHA resin exhibited an excellent adsorption performance for Cu, Pb and Ni. The maximum adsorption capacities of Cu, Pb and Ni were determined to be 238.59, 232.48 and 115.77 mg·g, respectively. Based on the adsorption kinetics, the pseudo-second-order kinetic model was noted to fit well for all metal ions. The metal ion concentration as a function of the equilibrium adsorption capacity fitted well with the Langmuir isotherm, thus indicating the single layer adsorption process. The adsorption mechanism was investigated by using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), density functional theory (DFT) calculations, X-ray photoelectron spectroscopy (XPS) and adsorption isotherms. It was revealed that the PAHHA resin possessed multiple active sites, including -CONHOH, -CONH- and -COOH, which could strongly adsorb the metal ions. Specifically, the -CONHOH group displayed a high affinity by forming a stable five-membered ring with heavy metal ions. Overall, the developed resin exhibits advantages such as simple synthesis, inexpensive raw material and good recyclability, along with high adsorption ability, thus providing a new approach for efficiently treating wastewater contaminated with heavy metal ions.
重金属废水污染已成为全球性的生态挑战。本研究报道了一种新型的聚（6-丙烯酰氨基-N-羟基己酰胺）（PAHHA）树脂的开发，用于有效吸附重金属离子，包括 Cu、Pb 和 Ni。螯合树脂是通过 6-氨基-N-羟基己酰胺与聚丙烯酸树脂之间的接枝反应合成的，因此含有偕羟肟酸和酰氨基基团。批量吸附实验表明，PAHHA 树脂对 Cu、Pb 和 Ni 表现出优异的吸附性能。确定 Cu、Pb 和 Ni 的最大吸附容量分别为 238.59、232.48 和 115.77 mg·g。基于吸附动力学，发现伪二阶动力学模型很好地适用于所有金属离子。金属离子浓度与平衡吸附容量的关系很好地符合 Langmuir 等温线，表明是单层吸附过程。通过傅里叶变换红外光谱（FT-IR）、扫描电子显微镜（SEM）、密度泛函理论（DFT）计算、X 射线光电子能谱（XPS）和吸附等温线研究了吸附机理。结果表明，PAHHA 树脂具有多个活性位点，包括 -CONHOH、-CONH-和 -COOH，可与金属离子强烈吸附。具体来说，-CONHOH 基团通过与重金属离子形成稳定的五元环表现出高亲和力。总的来说，开发的树脂具有合成简单、原料廉价、可回收性好、吸附能力强等优点，为高效处理重金属离子污染废水提供了新途径。
