Degradation Of Phenol And Its Analogues In Water By Heterogeneous Fenton Like Process

With the development of industrialization,more and more wastewater is discharged and the composition is more and more complex.The removal of pollutants in industrial wastewater has gradually become an important research field.Wastewater must be treated more thorough to reduce the adverse impact of industrial development on the environment.There are many methods to degrade organic matters in water.Advanced oxidation process（AOPs）has emerged as a relatively clean and efficient method among other catalytic oxidation processes,which make materials,such as H₂O₂,O₃ or O₂,to produce highly active substances in water for the degradation of organic.If appropriate catalyst is selected,it can achieve twice the result with half the effort.In this paper,benzenes were selected as the research object,and copper and silver were the active metal elements in the catalyst.The heterogeneous Fenton-like method was used to study the effect of different catalysts on the oxidation of organic compounds in water by H₂O₂and O₃.The degradation degree of organic compounds in solution was evaluated by COD,TOC and UV Vis.The crystal structure,specific surface area and pore size of the catalyst were studied by several characterization methods.The catalytic oxidation of aqueous phenol and aniline using H₂O₂ as oxidizing agent was studied in a round bottomed flask.The removal rates of COD and the UV absorption spectrum were calculated and measured.The effects of reaction temperature,solution p H,metal reduction and Cu O calcination time of the reaction were studied.The reaction temperature was the most important factor.The influencing factors of metal leaching were studied.The metal leaching decreased obviously after reduction,while the roasting time had a little effect on the metal leaching.It was also found that the faster the reaction rate,the lower the dissolution.The concentration of phenol and H₂O₂ were 280 mg/L and 0.1 mol/L,respectively.The results showed that the best catalyst was Cu/Al₂O₃（5 g/L）（without adjusting the p H of the solution）.The COD removal rates of Cu/Al₂O₃ were 89%in 60 min and 93%in 120 min at 70℃,respectively.The results of aniline oxidation were as follows.The removal rates of COD was only 79%in 60 min under the same conditions with phenol,which indicated that aniline was more difficult to be oxidized than phenol and needed stronger reaction conditions for degradation.The degradation of aqueous phenol and aniline using O₃ as oxidizing agent was studied in a bubble reactor.The COD and TOC removal rates and UV absorption spectrum of phenol aqueous solution were monitored.The effects of ozone production and calcination time of catalyst on the reaction were studied.The catalytic oxidation of phenol was carried out at 40℃.The concentration of phenol,the dosage of Cu/Al₂O₃ and the yield of O₃ was 280 mg/L,5 g/L and 20 g/L,respectively.The COD removal rates was more than 99%in 60 min.In the catalytic ozonation of aniline,the effects of ozone yield,support and catalyst calcination time on the reaction were studied.The ozone yield had the greatest effect on the reaction,followed by the support,and the catalyst calcination time had no obvious effect on the reaction.The removal rates of COD was 88%in 60 min at the same conditions with phenol（O₃ yield was 15 g/L）.The results of which showed that oxidizability of ozone was stronger than H₂O₂.