Study On The Catalytic Wet Air Oxidation Of Phenolic Wastewater With Copper Based Catalyst

Phenolic compounds are important, but poisonous chemical materials. Phenolic wastewater is very toxic to person and ecosystem, so the treatment of it is paid attention to by all the countries. Catalytic wet air oxidation (CWAO) is an effective method to treat the high concentration toxic organic compounds which hardly degraded in normal treatment. Its high effectiveness, low energy consumption, and no secondary pollutants make it attractive in the treatment of phenolic wastewater.The kinetics of phenol degrading was studied in presence of Cu2+. The effect of initial phenol concentration, copper ion concentration, temperature, oxygen atmosphere, etc. on the removal of COD was investigated. The results show that the reaction rate greatly relies on the reaction conditions. The favorite operation condition is Cu2+ 150 mg/L, initial phenol concentration 1000 mg/L, 140 and O2 0.6MPa. The CWAO process of phenol can be very well described by a modified generalized kinetics model. The largest SD (standard deviation) between experimental and calculation is 1.53%, and the least is 0.21%.Heterogeneous copper catalyst is easy to be separated from the aqueous solution. CuO catalyst and Cu-Zn-Al-0 catalyst were prepared with citric acid Sol-Gel method and characterized with XRD SEM, which could indicate the microstructure of the catalyst. CuO catalyst is solvate in reaction solution. About 160 mg/L Cu2+ wassolved into water when the CuO catalyst dosage was 1.0 g/L. However, only 160 mg/L Cu2+ was solved out from Cu-Zn-Al-0 catalyst. The Cu-Zn-Al-0 catalyst showed more active for phenol oxidation when the catalyst was prepared under conditions: salts : citric acid (molar ratio) = 1:1, preparation temperature 65, dried on 130, calcined 6h at 600. The COD removal rate was 57.5% after 30 minutes reaction and 69.4% after 70 minutes reaction.