摘要
采用溶胶-凝胶及沉积光还原法获得等离子体修饰TiO_2/有机累托石复合物(Ag@AgCl-TiO_2/OREC),再与季铵化壳聚糖(QCS)通过反相悬浮法制备了Ag@AgCl-TiO_2/OREC/QCS复合微球,表征了微球结构与形貌,测试了其光吸收性能。扫描电镜结果显示所制备微球具有疏松结构和粗糙表面。紫外可见吸收光谱分析表明,经等离子体修饰后,复合微球对可见光吸收明显增强。采用正交实验方法,确定了微球去除甲基橙最佳条件,在甲基橙的初始浓度为20 mg/L,pH=4,温度为20℃,微球用量为0.1 g时的甲基橙去除率高达99.4%。该微球可望用于化工废水处理。
Plasma modified TiO_2/organic rectorite composites(Ag@AgCl-TiO_2/OREC) were obtained by sol-gel method, deposition and photo-reduction. Then, Ag@AgCl-TiO_2/OREC/QCS composite microspheres were fabricated by inverse suspension method using Ag@AgCl-TiO_2/OREC and quaternized chitosan(QCS). The structure and morphology of the prepared microspheres were characterized and their optical absorption properties were tested. SEM shows that the microspheres have loose structure and rough surface. UV-vis spectra show that the visible light absorption of the composite microspheres is enhanced significantly after plasma modification. The optimum conditions for removal of methyl orange onto Ag@AgCl-TiO_2/OREC/QCS composite microspheres were determined by orthogonal test. The results show that the optimum conditions for removal of MO is that solution pH is 4, the initial concentration of MO is 20 mg/L, the temperature is 20 ℃, the amount of prepared microspheres is 0.2 g, and the removal rate of MO is as high as 99.4%. The microsphere is expected to be used for chemical wastewater treatment.
引文
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