4种高级氧化法处理高浓度正丙醇废水的动力学比较

研究了1%和10%(V/V)模拟正丙醇废水在UV/TiO2体系、UV/H2O2体系、Fe2+/H2O2体系和UV/TiO2/Fe2+/H2O2体系等4种工艺条件下的降解动力学过程,对比了降解动力学特点及工艺参数对动力学常数的影响,优化工艺参数。结果表明,UV/TiO2体系和Fe2+/H2O2体系的降解过程可分为零级反应阶段和一级反应阶段,转折点分别在反应开始后2 h和氧化剂浓度为6.7 g/L,UV/H2O2体系和UV/TiO2/Fe2+/H2O2体系分别符合零级反应和一级反应规律;相同工艺参数条件下,6 h反应后,组合工艺UV/TiO2/Fe2+/H2O2体系在处理效率达85%,比前3个体系分别高52.0%、8.3%和32.0%,与UV/TiO2体系和Fe2+/H2O2体系的处理效率之和持平,其协同效应提高了速率常数,在目标物浓度降低时依然可维持较高降解速率。而目标物浓度提高10倍后,UV能量利用率提高35.5倍,氧化剂用量是Fe2+/H2O2体系的1/7.1。

Kinetic comparison on treatment of wastewater containing high concentration of 1-propanol with four types of advanced oxidation processes

The kinetic research on 1% (V/V) 1-propanol polluted wastewater treated by four types of processes,i.e.,UV/TiO₂,UV/H₂O₂,Fe²⁺/H₂O₂ and UV/TiO₂/Fe²⁺/H₂O₂,was carried out.Furthermore,the kinetic characteristics of the degradation reaction and the effect of the operation parameters on kinetic constants were investigated in view of the optimization for the system.The experimental results indicated that the procedure of degradation reaction by UV/TiO₂ process and Fe²⁺/H₂O₂ process follows two reaction steps including zero order and first order reaction,displaying the turning point at the reaction duration of 2 h and the H₂O₂ concentration of 6.7 g/L,respectively.In particular,the processes of UV/H₂O₂ and UV/TiO₂/Fe²⁺/H₂O₂ solely complied zero order reaction and first order reaction,respectively.After 6 h degradation,the process of UV/TiO₂/Fe²⁺/H₂O₂ obtained the removal efficiency of above 85%,which was 52.0%,8.3% and 32.0% higher than that of the former three processes respectively under the same conditions.Furthermore,the process of UV/TiO₂/Fe²⁺/H₂O₂ showed the equivalent degradation efficiency as the integrated value provided by the process of UV/TiO₂ and Fe²⁺/H₂O₂.The high reaction constant for the process of UV/TiO₂/Fe²⁺/H₂O₂ due to the synergy effect keeps the rather good degradation performance on the removal of 1-propanol,even though at the low concentration.Additionally,the energy efficiency of UV irritation increased to 35.5 times,when the concentration of 1-propanol increased to 10 times,while the consumption of oxidant occupied 1/7.1 of the amount consumed in Fe²⁺/H₂O₂ system.