Study On Catalytic Degradation Of Adsorbed Aromatic Ring Compounds Under Irradiation Of Microwave Coupled With Ultraviolet

Aiming at the problems of wide sources, serious hazard and hard degradation ofaromatic ring compounds, a novel composite techniques of microwave coupled with UVradiation and catalytic degradation were applied to treat phenol, naphthol andrhodamine B in the research. The degradation effects and processing conditions of thetechnique were studied, and a novel functional material, MnO₂/Al₂O₃complex, whichhas microwave-absorbing, pollutant-adsorption and catalytic oxidation performance,was prepared. Significant degradation efficiency was achieved.MnO₂as a high-depleting substances in the UV, it can increase the temperaturerapidly, and MnO₂as the catalyst in many chemical reaction.MnO₂was used as catalystin the system, and phenol was adsorbed on activated alumina degradable by microwaveUV radiation. The experimental condition showed that the highest degree ofmineralization of phenol could achieve95.19%when the air retention time was30s, themicrowave power was529W, the irradiation time was20min and the dosage of MnO₂was15g. MnO₂converted to Mn2O3when temperature been up to530oC in theMicrowave radiation under aerobic conditions. It will be regeneration use the hotconcentrated sulfuric acid. The effect is good when use the MnO₂which has beenregeneration many times, the degree of mineralization of phenol still achieve more than80%.A new material MnO₂/Al₂O₃was prepared by aluminate neutralization method onthe basis of catalyst MnO₂. The material can be rapidly heated to900oC higher thanMnO₂under microwave irradiation is a new type of composite absorbing material. Theadsorbent were characterized by BET, SEM, EDX, and indicate that: the material is amesoporous material, microwave irradiation causes specific surface area of the materialis lower slightly and pore volume and pore size of the material has increased. Theabsorbing properties of composites was studied, The results show that the absorbingproperties of composites by the impact of the proportion of MnO₂and Al₂O₃content,the microwave output power and the quality loss of the composites under microwaveirradiation.Using the new material MnO₂/Al₂O₃in microwave UV radiation catalyticoxidation system on the degradation of the adsorbed phenol alpha-naphthol andrhodamine B. The experimental results showed that the degree of mineralization ofphenol in the microwave UV catalytic MnO₂/Al₂O₃materials could achieve90%andthe alpha-naphthol was80.58%when the irradiation of microwave UV time was20min,the microwave power was529W, the air flow was0.56L/min. at the same time thedegree of mineralization of rhodamine B achieved61.52%, when air flow was 0.4L/min.