Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China; University of Chinese Academy of Science, Beijing 100049, China.
Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
J Hazard Mater. 2021 Jun 15;412:125284. doi: 10.1016/j.jhazmat.2021.125284. Epub 2021 Jan 30.
Highly selective and efficient removal of ionic pollutants, including ionic organic compounds and heavy metal ions from water, is still a huge challenge due to the complex nature of polluted water. To meet this challenge, we presented the synthesis of bifunctionalized polyethyleneimine-based sponges through cryo-polymerization via BDDE as the crosslinker followed by bifunctional modification with glycidyl trimethylammonium chloride (GTAC) and phenyl glycidyl ether (PGE), which simultaneously afford quaternary ammonium cation (strongly basic and hydrophilic) and phenyl (hydrophobic) functionalities, respectively. As a result, a hybrid hydrophilic-hydrophobic sponge is generated that could stably be suspended underwater due to the co-operative effect of the water-absorbing hydrophilic domain and the hydrophobic domain generating buoyancy. The quaternized and phenyl-functionalized PEI-based sponge (S) demonstrated highly selective and efficient removal of anionic pollutants from water, including diclofenac sodium (DIC), methyl orange (MO) and chromium (Cr(VI)) with co-existing interferences. The Langmuir isotherms revealed the maximum adsorption capacities of 342.7 mg/g, 491.9 mg/g, and 242.7 mg/g for DIC, MO, and Cr(VI), respectively. The studies of adsorption mechanism suggested that the bifunctional S sponge indeed afford both strong anion-exchange interaction and π-π interaction toward organic pollutants DIC and MO, and the strong anion-exchange interaction can be the dominated adsorption mechanism for anionic DIC, MO and Cr(VI) species. The suspended S also demonstrated excellent reusability, which shows the potential of S for real applications.
由于受污染水的复杂性，高效选择性地去除水中的离子污染物（包括离子有机化合物和重金属离子）仍然是一个巨大的挑战。为了应对这一挑战，我们通过 BDDE 作为交联剂的冷冻聚合合成了双功能化聚乙烯亚胺基海绵，然后通过与缩水甘油三甲铵氯（GTAC）和苯缩水甘油醚（PGE）进行双功能化修饰，分别赋予季铵阳离子（强碱性和亲水性）和苯（疏水性）功能。结果，生成了一种混合亲水-疏水海绵，由于吸水亲水区和产生浮力的疏水区的协同作用，它可以稳定地悬浮在水下。季铵化和苯功能化的聚乙烯亚胺基海绵（S）展示了从水中高效选择性去除阴离子污染物的能力，包括来自水中的二氯芬酸钠（DIC）、甲基橙（MO）和铬（Cr(VI)），同时存在共存干扰。Langmuir 等温线显示了 S 对 DIC、MO 和 Cr(VI)的最大吸附容量分别为 342.7、491.9 和 242.7mg/g。吸附机制的研究表明，双功能 S 海绵确实提供了对有机污染物 DIC 和 MO 的强阴离子交换相互作用和π-π相互作用，对于阴离子 DIC、MO 和 Cr(VI)物种，强阴离子交换相互作用是主要的吸附机制。悬浮 S 还表现出优异的可重复使用性，这表明 S 在实际应用中的潜力。
