Hayashi Natsuki, Chen Jinhua, Seko Noriaki
Department of Advanced Functional Materials Research, Takasaki Advanced Radiation Research Institute, National Institutes for Quantum and Radiological Science and Technology (QST), 1233 Watanuki-machi, Takasaki, Gunma 370-1292, Japan.
School of Science and Technology, Gunma University, 1-5-1 Tenjin, Kiryu, Gunma 376-8516, Japan.
Polymers (Basel). 2018 Jul 5;10(7):744. doi: 10.3390/polym10070744.
To remove chromium from wastewater effectively, two types of nitrogen-containing fabric adsorbents, having amidoxime ligand groups and quaternary ammonium anion exchange groups, respectively, were prepared by radiation grafting. In brief, the amidoxime adsorbent is obtained by grafting of acrylonitrile (AN)/methacrylic acid (MAA) onto a nonwoven fabric and subsequent amidoximation with hydroxylamine, while the ammonium adsorbent is obtained by grafting of chloromethylstyrene (CMS) followed by quaternization with trimethylamine. The AN/MAA-grafting reaches a high degree of grafting more than 100%, and the resulting amidoxime adsorbent reaches a high amidoxime density of 4.53 mmol/g. On the other hand, the CMS-grafting reaches a much higher degree of grafting above 200%, and the resulting ammonium adsorbent reaches a high ammonium density of 3.51 mmol/g. FTIR/ATR and TGA/DTA are used for the characterization of the grafted fabrics as well as the relevant fabric adsorbents. Furthermore, the chromium removal of the prepared fabric adsorbent is tested in both batch and column modes. It has been confirmed that the chromium removal was largely dependent on the pH of the solution. At pH 5.0, the amidoxime adsorbent shows a high Cr(III) adsorption capacity of 31.68 mg/g, while the ammonium adsorbent shows a much higher Cr(VI) adsorption capacity of 130.65 mg/g.
为了有效去除废水中的铬，通过辐射接枝制备了两种含氮织物吸附剂，分别具有偕胺肟配体基团和季铵阴离子交换基团。简而言之，偕胺肟吸附剂是通过将丙烯腈（AN）/甲基丙烯酸（MAA）接枝到无纺布上，随后用羟胺进行偕胺肟化而获得的，而铵吸附剂是通过接枝氯甲基苯乙烯（CMS），然后用三甲胺进行季铵化而获得的。AN/MAA接枝达到了超过100%的高接枝率，所得偕胺肟吸附剂达到了4.53 mmol/g的高偕胺肟密度。另一方面，CMS接枝达到了高于200%的更高接枝率，所得铵吸附剂达到了3.51 mmol/g的高铵密度。傅里叶变换红外光谱/衰减全反射（FTIR/ATR）和热重分析/差示热分析（TGA/DTA）用于表征接枝织物以及相关的织物吸附剂。此外，在分批和柱模式下测试了所制备的织物吸附剂对铬的去除效果。已经证实，铬的去除很大程度上取决于溶液的pH值。在pH 5.0时，偕胺肟吸附剂对Cr(III)的吸附容量高达31.68 mg/g，而铵吸附剂对Cr(VI)的吸附容量更高，为130.65 mg/g。
