通过对玉米秸秆进行化学改性嫁接季氨基官能团, 制备了一种新型的阴离子吸附剂, 用于深度去除水体中的六价铬.通过扫描电镜 (SEM) 、红外光谱 (FT-IR) 分析发现:季氨基被成功嫁接到秸秆基质上, 改性后秸秆内表面沟壑较多, 比表面积增大.热力学与动力学研究显示:玉米秸秆基吸附剂吸附Cr (Ⅵ) 的过程符合Langmuir模型和准二级动力学模型, 属于单分子层化学吸附, 最大吸附量可达15.63 mg/g, 远大于D311A树脂吸附容量, 且40 min左右即可达到平衡, 最佳吸附pH为3～7.通过柱吸附实验研究发现:5 mL吸附剂处理含铬废水的体积可达3 000 mL, 吸附饱和的吸附剂通过强酸脱附再生, 多次循环吸附后处理体积几乎不变, 表明本文制备的秸秆基吸附剂具备较好的应用前景.%In this work, a novel corn straw-based adsorbent (MCS) was fabricated for enhanced removal of hexavalent chromium from water by grafting amine groups onto the corn straw (CS).The amine groups were successfully grafted onto straw substrate, and the modified inner surface has more gullies and larger specific surface area, as further demonstrated by FT-IR and Scamming electron microscope (SEM) spectroscopy studies.Thermodynamic and kinetic experiments showed that the adsorption process follows Langmuir model and quasi-second-order kinetic model.The maximum adsorption capacity was 15.63 mg/g, which was much larger than the D311 A resin, and the adsorption reached equilibrium within 40 minutes.The optimum adsorption pH was between 3 and 7.The column adsorption experiment indicated that the volume of chromium-containing wastewater treated by 5 mL adsorbent could reach 3 000 mL.The exhausted adsorbent could be effectively regenerated by acid solution for repeated use with negligible capacity loss.The results suggested that MCS has a great potential in efficient removal of Cr (Ⅵ) from contaminated waters.
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