Conversion And Utilization Of Aromatic Hydrocarbons In Wastewater

Industrial wastewater treatment is to separate pollutants from wastewater or transformthem into harmless or stable substances or separate substances.Industrial wastewater has different characteristics due to the different raw materials,production processes and products.This paper deals with the characteristics of industrial wastewater.The main research contents include:（1）An experimental study on the preparation of o-nitrobromo benzyl from o-nitrotoluene was carried out.The effects of reaction temperature,catalyst type,ratio of raw materials and concentration of hydrogen bromide on bromination of o-nitrotoluene were investigated.In bromination reaction,HBr/H₂O₂ is used as bromine source,ferric chloride as catalyst and AIBN as a free radical initiator.The yield of O nitro bromide is 88.68%under the ratio of n（o nitrotoluene）:n（hydrobroic acid）:n（hydrogen peroxide）is 1:1.2:1.2 and the reaction temperature is 80℃.The structure of the products obtained by bromination and etherification was characterized by IR,¹H-NMR and MS,and the hydrolysis of the byproduct of etherification was obtained by the hydrolysis of the byproduct,thus the optimization of the process was achieved.（2）Experimental research on wastewater containing alcohol and hydrogen bromide was carried out.Under the catalysis of HBr/H₂O₂,n-propanol,n-butanol and n-pentyl alcohol can produce corresponding esters to reduce the COD of industrial alcohol wastewater.By exploring the effect of the amount of catalyst,the reaction time and the type of extractant on the catalytic oxidation of alcohol,at the reaction temperature of 25℃,m（alcohol）:m（hydrobroic acid）:m（hydrogen peroxide）is 1:0.7:0.7,dichloromethane as the extractant and the concentration of 42 mg/mL in the COD of n-butanol,n-butanol and n-pentanol wastewater the removal rates were 86.87%,86.31%and 85.83%respectively.（3）An experimental study on treatment of pyridine industrial wastewater by Fenton process was carried out.This paper explores the effects of H₂O₂’s input mode and dosage,initial pH value and reaction temperature on the degradation of pyridine wastewater.It was found that when the reaction temperature was 30℃,and the initial pH was 3,the degradation of pyridine wastewater was the best,and the degradation rate of COD was 92.3%.