School of Civil Engineering & Architecture, Wuhan University of Technology, Wuhan, 430070, People's Republic of China.
Laboratory of Organometallics, Catalysis and Ordered Materials, State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, 430070, People's Republic of China.
Environ Sci Pollut Res Int. 2018 Jun;25(18):17830-17841. doi: 10.1007/s11356-018-1941-2. Epub 2018 Apr 20.
Magnetic chitosan particles (MCS) were chemically grafted by m-phenylenediamine (mPD) forming a distinctive shell layer with abundant nitrogenous functional groups and used as an adsorbent for the effective removal of Cr(VI) from aqueous solution. By interaction among functional groups in the facile oxidative polymerization process, the grafting of mPD and its polymers on MCS surface was innovatively realized. Through Fourier-transformed infrared spectroscopy, energy dispersive spectrometer, X-ray photoelectron spectroscopy, etc., the chemical properties of MCS before and after modification were characterized and the concurrent reduction-adsorption mechanism in Cr(VI) adsorption by mPD-MCS was carefully analyzed. The maximal Cr(VI) removal performance of mPD-MCS reached 227.27 mg/g, which was significantly better than that of the original MCS. The analysis indicated that Cr(VI) could be efficiently reduced to Cr(III) and the removal of Cr(VI) and Cr(III) was through adsorption and chelation simultaneously by mPD-MCS. Results also indicated that the concurrent reduction-adsorption was enhanced by protonation of nitrogenous functional groups under low pH. The obtained results suggest that mPD-MCS has a good potential in removal and detoxication of Cr(VI) from aqueous solutions.
磁性壳聚糖颗粒（MCS）通过间苯二胺（mPD）化学接枝，形成具有丰富含氮官能团的独特壳层，可用作从水溶液中有效去除 Cr(VI) 的吸附剂。通过在简便的氧化聚合过程中官能团之间的相互作用，创新性地实现了 mPD 和其聚合物在 MCS 表面上的接枝。通过傅里叶变换红外光谱、能量色散光谱仪、X 射线光电子能谱等手段，对修饰前后 MCS 的化学性质进行了表征，并仔细分析了 mPD-MCS 吸附 Cr(VI)时的同时还原-吸附机制。mPD-MCS 的最大 Cr(VI)去除性能达到 227.27mg/g，明显优于原始 MCS。分析表明，Cr(VI)可被高效还原为 Cr(III)，mPD-MCS 同时通过吸附和螯合作用去除 Cr(VI)和 Cr(III)。结果还表明，在低 pH 下，含氮官能团的质子化增强了同时还原-吸附作用。研究结果表明，mPD-MCS 在从水溶液中去除和解毒 Cr(VI)方面具有良好的应用潜力。
