Experimental Study On The Oxidation Of Humic Acid In Secondary Sedimentation Tank Water By Microwave Activated Carbon Supported Copper

With increasingly shortage of water resources in our country,treatment and reuse of municipal sewage can effectively alleviate this problem,the membrane technology is one of the main technologies of municipal sewage advanced treatment.However,there is still a small amount of organic matter in the tail water of the municipal sewage plant,and humic acid is the main component of organic compounds in the tail water of the second sedimentation tank.These organisms is the main factor causing membrane fouling,and therefore it is very important to study how to further remove the dissolved organic matter in the tail water.In this paper,the experimental study on the simulated wastewater of humic acid and the tail water of the municipal sewage plant was carried out by using microwave synergistic activated carbon.Two kinds of catalysts were prepared with copper powder activated carbon?Cu/PAC?and activated carbon?Cu/GAC?by the method of roasting after impregnating,from which made a characterization analysis about the morphological structure and the load of copper;The effects of different factors on the catalytic oxidation treatment of humic acid and the tail water of the municipal sewage plant were investigated by Optimal operating conditions.Furthermore,the mechanism of catalytic oxidation of activated carbon by microwave was preliminarily explored.The following conclusions are mainly drawn:?1?The optimum conditions for the preparation of the catalyst Cu/PAC were determined as consistency of impregnating of 0.2mol/L,baking temperature of 300?,baking time of 3h;The optimum conditions for Cu/PAC were determined as consistency of impregnating of 0.3mol/L,baking temperature of 300?,baking time of 3h.By making a characterization analysis about the two kinds of catalyst,it can be found that the difference between two kinds of activated carbon catalyst load.Namely,the surface of the activated carbon carrier in the first two forms is flat and smooth,while the surface of the copper activated carbon after the load is not smooth and smooth before load.At the same time,structural differences is not big,and also did not present a clear crystal structure,the amorphous copper to copper oxidedispersion of load on the carrier surface,but the specific surface area and entrance compared to before the load is increased,the aperture is the opposite.?2?In this paper,two kinds of catalytic oxidation Cu/PAC,Cu/GAC treatment of humic acid by microwave with copper activated carbon H₂O₂ as catalyst were established.For the catalyst Cu/PAC,Catalyst input 1 g/L,H₂O₂ dosage 0.9 ml/L,pH=3,Microwave Power 400 W;when microwave time is 4 min,It is the best condition for the test,and the removal rate of humic acid can be achieved 94.63%;For the catalyst Cu/PAC,Catalyst input 8 g/L,H₂O₂ dosage 1.5 ml/L,pH=6,Microwave Power 400 W;when microwave time is 4 min,It is the best condition for the test,and the removal rate of humic acid can be achieved 91.56%.?3?By comparison,two kinds of catalytic oxidation Cu/PAC,Cu/GAC treatment of humic acid by microwave with copper activated carbon H₂O₂ as catalyst was significantly better than other processes in the experiment.The removal mechanism of humic acid is mainly adsorption and catalytic oxidation.Adsorption is the main function of removing humic acid molecules at the initial stage of reaction.As the time of microwave radiation increases,the catalytic oxidation reaction begins to take effect,and the hydroxyl radicals?·OH?produced in the reaction process are the important active substances of the catalytic oxidation reaction.The results show that the microwave—catalyst—H₂O₂ system has high removal rate of humic acid and short reaction time used in this study.?4?In this paper,the experiment of two kinds of catalytic oxidation Cu/PAC,Cu/GAC treatment of humic acid by microwave with copper activated carbon H₂O₂as catalyst has been proved:For the catalyst Cu/PAC,Catalyst input 1.5 g/L,H₂O₂dosage 1.0 ml/L,pH=6,Microwave Power 400 W;when microwave time is 4 min,It is the best condition for the test,and the removal rate of humic acid can be achieved 93.56%;For the catalyst Cu/PAC,Catalyst input 10g/L,H₂O₂ dosage 1.5ml/L,pH=6,Microwave Power 400 W;when microwave time is 4 min,It is the best condition for the test,and the removal rate of humic acid can be achieved92.55%.The mechanism of removal mechanism of humic acid in wastewater was simulated by microwave synergistic copper activated carbon catalytic oxidation technology.