大面积壳聚糖无纺布的吸附性能及其分离回用强化

Adsorption Performance of Large Scale Chitosan Nonwoven and Its Enhancement of Separation and Reuse

针对壳聚糖类绿色低值吸附材料难以分离及回用的不足,构建了一类适用于无纺布类吸附材料的吸附装置。吸附装置为套筒结构,用以固定及最大限度地展开无纺布吸附材料。同时,考察了将该装置对染料废水的处理性能,探讨了壳聚糖无纺布对染料废水吸附去除过程中壳聚糖无纺布的用量、处理时间、染料初始浓度以及体系p H的影响。结果表明壳聚糖无纺布质量在4~8 g之间,处理时间在90~120 min之间,废水pH在3~7范围之间,染料C.I.Acid Red 73的去除效果达到最佳,去除率可达90%以上,吸附容量为88.43 mg/g。此外,通过SEM、XRD及XPS一系列表征手段,揭示了壳聚糖无纺布对染料的吸附主要机制与普通壳聚糖基吸附材料相似,通过壳聚糖分子中的质子化的活性氨基与染料分子中的阴离子基团的静电结合实现。

In this study, in order to overcome the solid/liquid separation inconvenience of chitosan powder adsorbents, a novel adsorption device with the sleeve cylinder was designed to match the chitosan nonwoven for the sake of easy separation.The inner cylinder is porous and wrapped by chitosan nonwoven.Moreover, the performance of the adsorption device was studied.Then, the effect of the dosage of chitosan nonwoven, reaction time, the initial concentration of dye and pH were discussed.The results showed that, the dye removal rate can reach above 90% when the dosage of chitosan nonwoven is 4~8 g with 90~120 min reaction time.In this system, the sorption of C.I.Acid Red 73 to chitosan nonwoven could maintain high efficiency in a wide pH range from 3 to 7 with a maximum adsorption capacity of 88.43 mg/g.Besides, through SEM, XRD and XPS, it reveals the electrostatic adsorption of AR73 onto the-NH.＋3 sites, which is similar to common chitosan-based adsorbent.