Study On The Treatment Of Analog Azo Dyes Wastewater Menthl Orange Solution

Azo dyes waste water is not only high chromatic, strong noxious, but also difficult to degrade and easy to discompose to carcinogenic aromatic amine under deoxidization condition. So, azo dyes waste water must be treated urgently. In this thesis, methyl orange solution, which has azo dyes structure, was studied comprehensively by vacuum membrane distillation (VMD) techniques, microwave techniques, ultrasonic techniques and Fenton reagent techniques. With the decoloration of methyl orange, removal ratio of COD and the change of structure reflected by UV spectrum as criteria, the influence of the technical conditions of above methods on the disposal of methyl orange were systemically studied. Furthermore, decomposition mechanism of the azo dyes and the assemble techniques of above methods was discussed. Methyl orange solution was disposed by VMD. The results indicated that, first, with the enhance of feed-in temperature, the diffuse rate of the component in disposal solution and saturated vapor pressure of hot-side solution increased. It is helpful to enhance degradation rate and COD removal ratio. Second, the increase of feed-in flow accelerated heat and mass transfer to enhance the separation efficiency. Third, when cold-side pressure was reduced, the process impetus and film flux reduced, but the degradation ratio and COD removal ratio and the methyl orange solution separation efficiency enhanced. Methyl orange solution was disposed by microwave field techniques. The results demonstrated that, first, the degradation ratio and COD removal ratio of low concentration(<50mg/L) methyl orange solution were influenced obviously by microwave. Second, when the disposal effect was same, temporal efficiency was greatly enhanced by microwave field combined with Fenton techniques. when microwave was applied in degrade methyl orange solution, there was non-heat effect, so, reaction kinetics was changed and active energy was reduced. UV-Vis spectrum indicated that the phenyl structure and naphthyl structure of methyl orange were destroyed, methyl orange solution was degraded. Methyl orange solution was disposed by ultrasonic field and ultrasonic field combined with Fenton techniques. The results showed that ultrasonic field didn't obviously effect on methyl orange structure, but Ultrasonic could accelerate Fenton reagent to degrade methyl orange and increase reaction rate of ·OH. Ultrasonic could accelerate the degradation of methyl orange, enhance the removal rate of COD and optimize efficiency of Fenton reagent. In a word, ultrasonic coupled with Fenton reagent was an efficient method to degrade methyl orange.