Efficient removal of Cr(VI) from water by quaternized chitin/branched polyethylenimine biosorbent with hierarchical pore structure
Efficient removal of Cr(VI) from water by quaternized chitin/branched polyethylenimine biosorbent with hierarchical pore structure
复制标题
具有分级孔结构的季铵化甲壳素/支化聚乙烯亚胺生物吸附剂有效去除水中的Cr(VI)
DOI：
10.1016/j.biortech.2017.10.071
复制
发表时间：
2018-02-01
影响因子：
11.4
通讯作者：
Hu, Daodao
中科院分区：
文献类型：
--
作者：
Liang, Xingtang;Fan, Xiaoyu;Hu, Daodao
在环氧氯丙烷的辅助下，季节化甲壳素与支化聚乙烯亚胺发生交联反应，合成了一种新型甲壳素生物吸附剂(QCP)，可有效去除水中六价铬。由于QCP同时具有季铵盐基和氨基，并具有层次化的孔结构，在25℃时，QCP的最大吸附容量为387.7 mg/g，吸附在40min内达到平衡，符合准二级动力学模型。QCP即使在高pH和竞争阴离子含量高的溶液中也能很好地发挥作用，并表现出良好的重复使用性。结果表明，铬(VI)吸附的主要机理是季铵基团和质子化氨基之间的静电吸引，其次是胺和羟基将铬(VI)部分还原为铬(III)。这项工作可能为甲壳素类生物吸附剂去除六价铬提供了可能性。
A novel chitin-based biosorbent (QCP) was synthesized by cross-linking quaternized chitin and branched polyethylenimine with the aid of epichlorohydrin for efficient removal of Cr(VI) from water. Because it possessed both quaternary ammonium groups and amino groups as well as the hierarchical pore structure, QCP presented a maximum adsorption capacity of 387.7 mg/g according to the Langmuir isotherm at 25 degrees C. The biosorption of QCP achieved the equilibrium within 40 min and followed the pseudo-second-order kinetic model. QCP worked well even in the solution with high pH and high content of competing anions and, it exhibited an excellent reusability. The main Cr(VI) uptake mechanism was confirmed to be electrostatic attractions between Cr(VI) anions and quaternary ammonium groups as well as the protonated amino groups, and followed by partial reduction of Cr(VI) to Cr(III) by amines and hydroxyls. This work may provide a potential for Cr(VI) removal by chitin-based biosorbents.