| 摘要: |
| 目前水环境污染物成分复杂，常用的化学沉淀法已很难将重金属污染物分类去除并资源化利用，由此产生大量的危废污染环境，需要二次处理。利用离子印迹技术对壳聚糖基水凝微球进行改性，制备具有对Cr (VI)特异识别性能的吸附材料(CTS-IGB），对其在单一Cr (VI)溶液和模拟电镀废水中的吸附行为特征进行研究。研究结果表明：在20℃、pH值为3时，CTS-IGB在单一Cr (VI)溶液和模拟电镀废水中Cr (VI)的吸附量在180 min内分别达到37.4 mg/g和44.3 mg/g，半饱和吸附时间t1/2仅分别为5.8 min和23.5 min；吸附行为符合准二级动力学。吸附等温线拟合表明吸附过程符合Freundlich模型；热力学参数表明吸附过程是放热反应且吸附后无序度减小；相比于未改性壳聚糖水凝微球，CTS-IGB在共存离子（模拟电镀废液及其他双组份溶液）存在下对Cr (VI)的选择性显著提高32%~74%。该材料可作为一种潜在的吸附材料用于污染水环境中Cr (VI)的分离及回收。 |
| 关键词: 壳聚糖 离子印迹 Cr (VI) 电镀废水 |
| DOI： |
| 分类号: |
| 基金项目:中央级公益性科研院所重点项目(Y418003) |
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| Selective Adsorption of Cr (VI) on Ion-imprinted Chitosan Gel Microspheres |
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CAI Weicheng, GUO Mulin
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Nanjing Hydraulic Research Institute
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| Abstract: |
| At present, the composition of water environmental pollutants is complex, and it is difficult to classify and remove the heavy metal pollutants and recycle them using the common chemical precipitation method, resulting in a large number of hazardous wastes that pollute the environment and require secondary treatment. The substrate chitosan gel microspheres were modified through ion-imprinted technology to synthesis of CTS-IGB, and subsequently employed as adsorbents for Cr (VI) removal selectively from single Cr (VI) solutions and simulated electroplating wastewaters. The results indicated that the Cr (VI) adsorption capacity of CTS-IGB reached 37.4 mg/g and 44.3 mg/g in single Cr (VI) solution and simulated electroplating wastewaters, respectively, when the pH was 3 and temperature was kept at 20℃. And the t1/2 were 5.3 minutes and 5.6 minutes, respectively. The experimental Cr (VI) adsorption data were well agreed with pseudo-second-order kinetic model. Freundlich isotherm model can best describe the equilibrium data of Cr (VI) adsorption. The thermodynamics parameters indicated that Cr (VI) adsorption on CTS-IGB was spontaneous, thermodynamically favorable and exothermic, and decrease in random. Comparing with the pristine chitosan gel microspheres, the Cr (VI) selective adsorption coefficient of CTS-IGB were increased 32%~74% in the presence of coexisting ions. The CTS-IGB can be used as a potential adsorption material for the separation and recovery of Cr (VI) in polluted water environment. |
| Key words: Chitosan Ion-imprinted Cr (VI) Electroplating Wastewater |
