Preparation Of Mn₂O₃ And Study On Its Activation Of Persulfate Degradation Of Ketoprofen

Water resources situation is not optimistic in our country,and the rapid economic development has also brought a heavy burden to the ecological environment.Among them,the most prominent problem is the growing water pollution.As a kind of water pollution,the micro-polluting of water has attracted wide attention of all mankind.Advanced oxidation technology based on sulfate radical(SO₄^·–)heterogeneously activated persulfate decontamination has been widely recognized.Compared with hydroxyl radicals?^·OH?,sulfate radical has the following advantages:it has a higher redox potential than hydroxyl radicals;the intermediate product is relatively stable;it can perform excellently in a wide range of pH;it can remove some refractory pollutants that can't be removed by hydroxyl radicals.In this paper,hydrothermal synthesis,solid phase synthesis and other methods were used to synthesize various manganese oxide?Mn₂O₃?.XRD,SEM,FTIR,TG-DSC,BET and XPS were used to analyze the prepared Mn₂O₃.Ketoprofen?KTP?was used as the degradation target,and the removal rate of KTP was taken as the experimental index,and the most suitable conditions for the preparation of the Mn₂O₃were obtained.From the results,it was found that the activation performance of the obtained cubic morphology of Mn₂O₃ at 500°C was the best.The effectiveness of the activated persulfate system was studied by using Mn₂O₃ with the best activation performance.The optimum conditions for the activated persulfate system were determined by orthogonal experiment.The temperature,pH,humus acid and chloride ions were investigated to the degradation effect.The results show that when the system is acidic,the removal effect of KTP is more ideal;the higher the temperature of the system,the better the degradation of KTP;in a certain concentration range,with the increase of the concentration of humic acid and chloride ion in the system,the degradation rate of KTP will gradually decrease.When the concentration of both ions exceeds a certain value,the degradation rate of KTP will not decrease with the increase of humic acid and chloride ion concentration.By comparing the persulfate system and the activated persulfate system,it is known that the addition of the Mn₂O₃ accelerates the decomposition rate of persulfate and increases the utilization rate of persulfate,thereby increasing the removal rate of KTP.The presence of SO₄^·–was directly detected by electron paramagnetic resonance?EPR?,which proved that Mn₂O₃ activated persulfate conforms to SO₄^·–theory.The reaction characteristics of methanol and SO₄^·–also prove the existence of SO₄^·–in the system.