State Key Laboratory of Separation Membranes and Membrane Processes/National Center for International Joint Research on Separation Membranes, School of Materials Science and Engineering, Tiangong University, Tianjin, 300387, China.
State Key Laboratory of Separation Membranes and Membrane Processes/National Center for International Joint Research on Separation Membranes, School of Materials Science and Engineering, Tiangong University, Tianjin, 300387, China.
Environ Res. 2022 Mar;204(Pt A):111943. doi: 10.1016/j.envres.2021.111943. Epub 2021 Aug 31.
As one of the main pollutants of water pollution, the potential toxicity of heavy metal ions always threatens the safety of human and nature. Therefore, how to effectively remove heavy metal ions has become an important research topic in environmental protection. In the existing research, adsorption method is outstanding from many methods because of its high adsorption efficiency and easy operation. In this study, different generations of hyperbranched polyamide-amine (PAMAM) were grafted onto PVDF membrane to obtain the membrane with high adsorption capacity for heavy metal ions. The structure and physicochemical properties of the membranes were evaluated by means of fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (FE-SEM), element analyzer and X-ray photoelectron spectroscopy (EDX). At the same time, various factors affecting the adsorption process were studied, and it was found that the adsorption behavior of copper ion (Cu) on the membrane conformed to the pseudo-first-order kinetic model and Langmuir isotherm model. Moreover, after comparing the adsorption effect of the modified membranes grafted with different generations of PAMAM, it was found that the membrane grafted with the third generation PAMAM had the best adsorption when the solution pH was 5, and its maximum adsorption capacity could reach 153.8 mg/g. After five adsorption-desorption cycles, its adsorption capacity can reach 72.83% of the first test, indicating that it has good recycling performance. The results show that the adsorption membrane has good application potential and research value.
作为水污染的主要污染物之一，重金属离子的潜在毒性总是威胁着人类和自然的安全。因此，如何有效地去除重金属离子已成为环境保护的重要研究课题。在现有研究中，吸附法因其高吸附效率和易于操作而从众多方法中脱颖而出。本研究通过接枝不同代数的超支化聚酰胺-胺（PAMAM）到聚偏氟乙烯（PVDF）膜上，得到了对重金属离子具有高吸附容量的膜。采用傅里叶变换红外光谱（FT-IR）、扫描电子显微镜（FE-SEM）、元素分析仪和 X 射线光电子能谱（EDX）等手段对膜的结构和理化性质进行了评价。同时，研究了影响吸附过程的各种因素，发现铜离子（Cu）在膜上的吸附行为符合准一级动力学模型和 Langmuir 等温吸附模型。此外，通过比较接枝不同代数 PAMAM 的改性膜的吸附效果，发现当溶液 pH 值为 5 时，接枝第三代 PAMAM 的膜具有最佳的吸附效果，其最大吸附量可达 153.8mg/g。经过五次吸附-解吸循环后，其吸附容量可达第一次测试的 72.83%，表明其具有良好的循环性能。结果表明，吸附膜具有良好的应用潜力和研究价值。
