Fenton氧化降解焦化废水的影响特性及动力学模型

为研究Fenton试剂氧化降解焦化废水的影响特性及动力学机理,采用小试烧杯实验考察初始COD、H2O2投加量、Fe2+投加量和反应温度等因素对处理效果的影响。结果表明,原水COD为260 mg/L、H2O2投加量为666mg/L、Fe2+投加量为200 mg/L、温度为298 K时,COD去除率达到89.53%;反应初始阶段COD氧化降解的表观反应动力学模型与实验数据得到较好的拟合,因此该动力学模型能较好地预测Fenton试剂对焦化废水的氧化降解情况;反应总级数为2.001 7,其中H2O2的反应分级数(0.568 5)高于Fe2+的反应分级数(0.494 0),说明Fenton氧化降解COD过程中H2O2浓度的影响比Fe2+的大;较低的反应活化能说明反应较易进行。

Influencing characteristics and kinetic model of coking wastewater degradation by Fenton oxidation

The influencing characteristics and kinetics mechanisms of the degradation of coking wastewater by Fenton reagent have been studied. Based on small beaker tests ,the influences of the factors ,such as initial concentration of COD,H2O2 dosage,Fe2+dosage,reaction temperature,etc. on the treatment effects are investigated. The results show that when the raw water COD is 260 mg/L,H2O2 dosage 666 mg/L,Fe2+dosage 200 mg/L,and temperature 298 K,the COD removing rate reaches 89.53%. The empirical reaction kinetic model which reflects COD oxidation degradation in the initial stage fits the experimental data quite well. Therefore ,the kinetics model can well predict the oxidation degradation situation of coking wastewater by using Fenton reagent. The total reaction series is 2.001 7 ,among which the ranked reaction series of H2O2(0.568 5) is higher than that of Fe2+(0.494 0). It indicates that in the process of COD oxidation degradation by Fenton,the influence of initial H2O2 concentration is greater than that of Fe2+. The lower reaction activation energy indicates that Fenton reaction can be conducted more easily.