改性活性炭与 H2 O2联用去除三氯酚的动力学分析

摘要

Fenton like system was formed by modified activated carbon combined with H2 O2 ,the removal of 2, 4,6-trichlorophenol (TCP)were analysed.The reaction kinetics was described by pseudo-first-order kinetic model and second-order kinetic model.It was found that pseudo-first-order kinetic model was effective.Different initial H2 O2 concentration,coefficient k of reaction kinetics was different.TCP decomposition was directly in-fluenced by •OH concentration catalysed with H2 O2 .With H2 O2 concentration increased,TCP decomposition increased.While H2 O2 concentration further increased,coefficient k decreased.Langmuir-Hinshelwood model was adopted to analyse TCP decomposition process in order to study TCP removal mechanism.When H2 O2 con-centration was 0.4 and 4 mg/L,the related coefficient was 0.943 and 0.989 respectively fitted by [TCP]and 1/kapp.It was good dependency that the interaction of adsorption and oxidation reaction caused by •OH between TCP and GACF1 M3 decided the whole reaction rate.%采用负载铁锰氧化物的活性炭与 H2 O2联用形成类芬顿系统,对2,4,6-三氯酚进行去除分析.分别采用拟一级动力学与二级动力学对反应过程进行拟合,发现TCP的降解采用拟一级反应动力学拟合效果更佳.H2 O2的初始浓度不同,动力学系数k 值也不相同.由于 TCP 的降解与催化 H 2 O 2所产生的OH•浓度直接相关,随着 H2 O2浓度的增加,TCP 的降解相应增加.然而,当 H2 O2的浓度继续增加时,k的值反而呈下降趋势.为进一步研究 TCP 降解机理,采用Langmuir-Hinshelwood模型对其降解过程进行分析,发现对[TCP]-1/kapp进行拟合,当 H2 O2浓度分别为0．4和4 mg/L 时,其相关系数为0．943和0．989,即相关性较好.表明 TCP 和 GACF1 M3表面的吸附和由羟基引起的氧化反应的相互作用决定整个反应的速率.