Fenton降解活性黑5的褪色动力学研究

Fenton Reagent Oxidation and Decolorizing Reaction Kinetics of Reactive Black 5 by On-line Spectrophotometry

利用在线分光光度法对Fenton试剂降解活性黑5模拟废水进行褪色行为研究,考察了FeSO4初始浓度、H2O2初始浓度、pH值、反应温度等因素对活性黑5褪色过程的影响规律.结果表明,Fenton氧化过程分为两个拟一级动力学过程,反应前期褪色速率常数(k1)和反应后期褪色速率常数(k2)相差约5倍.增大Fe2+的初始浓度和体系温度能够增加k1和去除率,且k1与Fe2+初始浓度线性相关,反应活化能为3.451 kJ/mol;H2O2初始浓度和pH值存在最佳值,分别为2.118 mmol/L和3.

Fenton reagent was employed to treat and decolorize the wastewater of reactive black 5 by on-line spec- trophotometry. The effects of FeSO4 concentration ,H2O2 concentration ,pH ,and temperature on the discoloration of RB- 5 were investigated. The results showed that there were two steps during Fenton oxidize process, and they all followed pseudo first order kinetics in the first region and second region. Decolorizing reaction rate constant in the first region （ kI ） and removal efficiency were increased by the rise of FeSO4 concentration and temperature. Initial FeSO4 concen- tration against k is linear correlation and the reaction activation energy is 3. 451 kJ/mol. The optimum initial H2O2 con- centration and pH are 2.118 mmol/L and 3, respectively.