纳米二氧化钛在膜反应器中循环光催化降解亚甲基蓝

以低压汞灯为光源,纳米二氧化钛为催化剂,对纳米二氧化钛在膜反应器中循环光催化降解亚甲基蓝进行了研究,探讨了催化剂加入量、进料速度对降解率和降解速率的影响。结果显示,当纳米二氧化钛加入量和亚甲基蓝进料速度一定时,在一定时间内亚甲基蓝的光催化降解可达到平衡,降解曲线出现拐点。随着催化剂加入量的增加或进料速度变慢,降解拐点前移,降解率提高。纳米TiO2加入量为2.0 g.L-1,进料速度为15 mL.h-1时,降解拐点时间为150 min,降解率高达到88%。对膜反应器截留效果及膜污染情况进行的分析表明,膜反应器对纳米TiO2有很好的截留作用,在连续补充料液的循环反应中,透过液中TiO2的浓度为2.836 mg.L-1时,TiO2损失率仅0.142%。

Cyclic Photocatalytic Degradation of Methylene Blue by Nano-TiO2 in a Membrane Reactor

The influences of nano-TiO2 dosage,MB addition velocity on the photocatalytic degradation of MB by nano-TiO2 in hollow fibriform membrane reactor were systematically investigated.Results show that the photocatalytic degradation efficiency increases with increasing nano-TiO2 dosage and decreasing MB addition velocity.Photocatalytic degradation reaches a balance in a certain period of time for a fixed proportion of nano-TiO2 dosage and MB addition velocity,and an inflexion can be observed on the curve of the photocatalytic degradation efficiency of MB versus degradation time in the cyclic membrane reactor.The shortest degradation time is 150 min and the highest degradation efficiency is 88% when the dosage of nano-TiO2 is 2.0 g·L-1 and the MB addition velocity is 15 mL·h-1.The filtering ability of the hollow fibriform membrane for nano-TiO2 was measured by analyzing the amount of nano-TiO2 on the surface of the hollow fibriform membrane and in the effluent.Up to 99.8% of the nano-TiO2 can be blocked by the hollow fibriform membrane under the experimental condition.