Ag/AgCl改性碳纳米管薄膜连续流光催化去除水中亚甲基蓝

Continuous-flow photocatalysis with Ag/AgCl modified carbon nanotubes filter towards methylene blue removal from water

为了探究Ag/AgCl光催化薄膜在连续流状态下对有机污染物的光催化性能,采用连续沉积方法制备了Ag/AgCl改性碳纳米管(CNTs)薄膜,以亚甲基蓝为目标污染物,利用光化学过滤器对亚甲基蓝的光催化脱色效果进行了探究。结果表明,在900μW·cm-2光强下,Ag/AgCl-CNTs复合薄膜在连续流光催化体系中对10 mg·L-1的亚甲基蓝去除率可达90%,比传统序批式反应体系高出70%以上,说明连续流体系的对流传质效果明显优于序批式体系的扩散传质效果。同时,Ag/AgCl的沉积显著改善了CNTs薄膜的光催化脱色性能。在最佳实验条件下,Ag/AgCl改性后,复合薄膜的光催化脱色效果比CNTs薄膜提高了40%。Ag/AgCl-CNTs多功能复合薄膜体系具有光催化降解和膜分离以及减缓膜污染等多重特性。

To investigate the photocatalytic performance of Ag/AgCl photocatalytic filters towards organic pollutants degradation under continuous-flow conditions,the Ag/AgCl modified carbon nanotubes(CNTs)filters were preparedby using the sequential deposition method,and the photocatalytic decolorization effect of the photochemical filter was studied when methylene blue(MB)was taken as a model compound.The results showed that the MB removal efficiency could reach 90%for the Ag/AgCl-CNTs hybrid filters in a continuous-flow photocatalys is system towards 10 mg·L-1 MB solution at illumination intensity of 900μW·cm-2,which was above 70%higher than that of conventional batch reactor.This indicated that the convection mass transfer effect in the former system was better than the diffusive mass transfer effect in the latter.Moreover,Ag/AgCl modification significantly improved the photocatalytic decolorization performance of Ag/AgCl-CNTs hybrid filters,and the decolorization efficiency of the hybrid filters was 40%higher than that of a CNT-alone filter under the optimal conditions.The Ag/AgCl-CNTs multifunctional composite filter system has multiple characteristics such as photocatalytic degradation,membrane separation and membrane fouling mitigation.