Research Of The Preparation Of Al₂O₃ Loaded Modified MnO₂ And The Advanced Treatment Of Coking Wastewater

The effective treatment of coal chemical wastewater is related to the sustainable development of coal chemical industry.In this study,hydrothermal synthesis method was used to prepare modified MnO₂,and the typical refractory organic compound quinoline was studied experimentally.The spherical catalyst doped with fly ash was prepared and its performance in the treatment of coking wastewater was studied.α-,β-andγ-MnO₂ were synthesized.Under the conditions of n _Mn(_Ac)₂:n _{Mn SO4}=5:5,140℃and 14 h,the best activity of MnO₂ was obtained.When the dosage of MnO₂ was 0.5 g/L and the reaction time was 60 min,the removal rate of quinoline was 88.21%.MnO₂-GO was synthesized with 0.6%GO,and the degradation rate of quinoline increased by 6%after 60 min reaction.MnO₂-NH₂-GO was synthesized.After 60 min reaction,the degradation rate of quinoline was 99.99%,and the activity of quinoline remained good after 4 times use.Doped with 6%Ca can improve the stability of the catalyst and reduce the leaching rate of Mn ions.The superoxide radical is the main free radical.Adding 1000 mg/L HCO3-,CO32-,SO42-and Cl-,the degradation rates were 89.57%,90.05%,91.94%and 87.92%,respectively,after reaction for 60 min.All of them had obvious inhibition on the degradation effect of quinoline.Adding 1 g/L sodium phosphate,the degradation effect of quinoline was only 70.07%,and the acid site on the surface was the active site of the reaction.The 3-5mm spherical catalyst was prepared by selecting the optimal doping ratio of 5%active component and 10%fly ash and adding additives.Under the conditions of 100 g/L catalyst and 10 mg/min ozone reaction for60 min,the COD removal rate of coking wastewater is 66.28%.The results show that the performance is improved after modification of amino and doping of GO,and doping of Ca is beneficial to the generation of oxygen vacancy.The doping of fly ash can reduce the cost and does not significantly affect the performance of the catalyst.The COD degradation experiment of coking wastewater shows that the catalyst prepared in this study has good catalytic effect and engineering application prospect.