Experimental Study On Deep Treatment Of Coking Waste Water By Fenton Method

Coking wastewater,whose pollutant composition and water quality characteristics are extremely complex,is a typical toxic and refractory industrial wastewater.Therefore,it is difficult to purify the wastewater to be dealt with by conventional biochemical treatment process,in which the the COD of secondary is still hard to reach the standard.In recent years,the national environmental protection standard for industrial wastewater has been constantly improved,and the promulgation of the "Ten Water Articles" makes the in-depth treatment and reuse of industrial wastewater more urgent.Fenton method is commonly used to treat refractory wastewater.However,the traditional fenton treatment process has such problems as large amount of iron sludge,narrow range of reaction pH,large consumption of hydrogen peroxide,and being sensitive to the charges of process parameters.In this work,the preparation and catalytic mechanism of?-Cu-Ce-Al2O3 catalyst based on copper and cerium were studied and a heterogeneous fenton catalytic system for coking wastewater was constructed.Phenol and quinoline are the main refractory components in coking wastewater.In this paper,the catalytic performance and mechanism of ?-Cu-Ce-Al2O3 catalyst towards studied with phenol and quinoline solutions were firstly studied in the laboratory.Then,the treatment efficiency of the heterogeneous fenton system and traditional fenton system was compared with coking wastewater from a steel enterprise in Hebei province.The results show that:1.Prepare ?-Cu-Ce-Al2O3 catalyst by sol-gel method.The best preparation conditions are:roasting time 6 h,roasting temperature 600?,copper-cerium molar ratio 2:1.The surface of ?-Cu-Ce-Al2O3 catalyst is irregular and coarse 'which helps to improve the specific surface area of the catalyst.Besides,the adding of Ce changes the structure of the catalyst and increased the specific surface area,which improved the contact of the catalyst with hydrogen peroxide,so as to improve the utilization rate of hydrogen peroxide.2.The main active substances in the heterogeneous fenton reaction system which is made up of ?-Cu-Ce-Al2O3 and hydrogen peroxide are hydroxyl radicals.The optimal reaction conditions of the reaction system are:the dosage of the catalyst is 1.2 g/L,the dosage of H2O2 is 45 mmol/L,and the pH of the reaction is 6.3.Phenol,quinoline and coking wastewater were treated by the heterogeneous fenton system constructed by ?-Cu-Ce-Al2O3 catalyst and the traditional fenton system.It can be found that the ?Cu-Ce-Al2O3 catalyst has a wider reaction pH range and higher catalytic oxidation efficiency under the optimal reaction conditions...