Liang Siwei, Tang Jingyi, Yao Shun, Zhu Weixia
School of Chemical Engineering, Sichuan University Chengdu 610065 People's Republic of China
School of Chemical Engineering and Energy, Zhengzhou University Zhengzhou 450001 People's Republic of China
RSC Adv. 2019 Jul 25;9(40):22907-22920. doi: 10.1039/c9ra04641k. eCollection 2019 Jul 23.
The highly efficient gel obtained the copolymerization of polyethylenimine (PEI) and poly(,-dimethylaminoethyl methacrylate) (PDMAEMA) was successfully applied for the removal of two anionic dyes (amaranth and sunset yellow) from their aqueous solutions. Moreover, the results of the adsorption experiments for sunset yellow and amaranth on the PEI/PDMAEMA gel demonstrate that the adsorption equilibrium both could be achieved within 1 h, and the maximum adsorption capacities were 757 mg g and 744 mg g under unoptimized conditions, respectively. Moreover, the PEI/PDMAEMA composite gel was found to be pH-sensitive and the addition of salts together with ionic strength were also explored for understanding the adsorption performance. In addition, it can be found from the studies of adsorption mechanism that it is mainly electrostatic adsorption; moreover, the separation process conforms to the Langmuir adsorption isotherm model and the pseudo second-order kinetic model, which is a spontaneous endothermic process. When the PEI/PDMAEMA gel was used in continuous flow column, it could handle large volumes of dye solution with very low concentrations due to its strong enrichment capacity. Finally, the desorption experiments show that the PEI/PDMAEMA gel is easier to regenerate and has a longer lifetime. Therefore, the high adsorption capacity and easy operation of adsorption for amaranth and sunset yellow on the PEI/PDMAEMA gel make it a potential application prospect for the practical removal of other kinds of similar pollutants.
通过聚乙烯亚胺（PEI）和聚甲基丙烯酸二甲氨基乙酯（PDMAEMA）共聚得到的高效凝胶，成功应用于从水溶液中去除两种阴离子染料（苋菜红和日落黄）。此外，苋菜红和日落黄在PEI/PDMAEMA凝胶上的吸附实验结果表明，吸附平衡在1小时内均可达到，且在未优化条件下，最大吸附容量分别为757 mg/g和744 mg/g。此外，发现PEI/PDMAEMA复合凝胶对pH敏感，还研究了盐的添加以及离子强度对吸附性能的影响。另外，从吸附机理研究可知，主要为静电吸附；而且，分离过程符合Langmuir吸附等温线模型和准二级动力学模型，这是一个自发的吸热过程。当PEI/PDMAEMA凝胶用于连续流柱时，由于其强大的富集能力，它能够处理大量低浓度的染料溶液。最后，解吸实验表明，PEI/PDMAEMA凝胶更容易再生且使用寿命更长。因此，PEI/PDMAEMA凝胶对苋菜红和日落黄具有高吸附容量且吸附操作简便，使其在实际去除其他种类类似污染物方面具有潜在的应用前景。
