Fenton氧化技术强化水中多环芳烃降解的条件优化  

Optimization of Fenton oxidation technology for enhancing polycyclic aromatic hydrocarbons degradation in water

作　　者：周娈 汪彤馨 陈旭文 凌婉婷[1] ZHOU Luan;WANG Tongxin;CHEN Xuwen;LING Wanting(Institute of Organic Contaminant Control and Soil Remediation,Nanjing Agricultural University,Nanjing 210095,China)

机构地区：[1]南京农业大学土壤有机污染控制与修复研究所,南京210095

出　　处：《农业环境科学学报》2025年第3期720-729,共10页Journal of Agro-Environment Science

基　　金：中国博士后科学基金项目(2023M731723,2024T170417);国家自然科学基金项目(42261144738,42307031);江苏省卓越博士后计划项目(2023ZB478);国家重点研发计划项目(2023YFC3708100)。

摘　　要：为解决芬顿(Fenton)氧化技术在实际去除水中多环芳烃(PAHs)时面临的去除不彻底、氧化剂利用率低以及水体基质破坏严重等问题,对Fenton技术的各种反应条件进行优化研究。本研究主要探究了关键因子如Fe^(2+)/H_(2)O_(2)比例、螯合剂柠檬酸浓度、反应时间、H_(2)O_(2)浓度以及污染物浓度对Fenton技术的影响。研究发现,PAHs的降解率随着反应时间的延长逐渐升高,但在48 h后趋于稳定。H_(2)O_(2)与Fe^(2+)是Fenton试剂的核心组分,Fe^(2+)通过破坏H_(2)O_(2)的O O键产生·OH降解污染物。PAHs降解的最佳H_(2)O_(2)浓度为1%,Fe^(2+)/H_(2)O_(2)添加比例为1/18(摩尔比),在此条件下,水中芴(FLU)、菲(PHE)、荧蒽(FLA)和芘(PYR)的降解率分别高达86%、99%、98%和100%。但当H_(2)O_(2)浓度或Fe^(2+)/H_(2)O_(2)添加比例过高时,短时间内产生大量的·OH会互相淬灭,而且过量的Fe^(2+)会与PAHs竞争消耗·OH,导致PAHs降解效率降低。柠檬酸通过调节水体pH、螯合Fe^(2+)等机制提高了PAHs的降解率,优化后的最佳柠檬酸浓度为20 mol·L^(-1),该条件下FLU、PHE、FLA和PYR在48 h的降解率分别为81%、78%、60%和100%,进一步延长时间后PAHs可被完全降解。此外,该Fenton技术对于水中低于0.1 mg·L^(-1)的PAHs降解效果最佳,4种PAHs的降解率均超过94%。研究通过系统探究各关键因子,确定了Fe^(2+)/H_(2)O_(2)添加比例、柠檬酸浓度、反应时间、H_(2)O_(2)浓度以及污染物浓度的最佳使用参数,可使Fenton氧化技术对水中PAHs的降解效果达到最佳。In order to solve the problems of incomplete removal,low oxidant utilization rate and serious water matrix damage in the actual removal of polycyclic aromatic hydrocarbons(PAHs)in water by Fenton oxidation technology,various reaction conditions of Fenton technology were optimized.This study mainly explored the influence of key factors such as Fe^(2+)/H_(2)O_(2) ratio,citric acid concentration of chelating agent,reaction time,H_(2)O_(2) concentration and pollutant concentration on Fenton oxidation technology.It was found that the degradation percentage of PAHs gradually increased with the extension of reaction time,but tended to be stable after 48 h.H_(2)O_(2) and Fe^(2+)were the core components of Fenton reagent,and the·OH was produced when the O O bond in H_(2)O_(2) was broken by Fe^(2+).The optimal H_(2)O_(2) concentration for PAHs degradation was 1%and the addition ratio of Fe^(2+)/H_(2)O_(2) was 1/18.Under these conditions,the degradation percentages of fluorene(FLU),phenanthrene(PHE),fluoranthrene(FLA)and PYR were as high as 86%,99%,98%,and 100%,respectively.However,when the concentration of H_(2)O_(2) and/or the addition ratio of Fe^(2+)/H_(2)O_(2) were too high,a large amount of·OH produced in a short time would quench each other,and excessive Fe^(2+)would also consume·OH in competition with PAHs,resulting in lower degradation efficiency of PAHs.Citric acid improved the degradation of PAHs by regulating solution pH and chelating with Fe^(2+).In this study,the optimal concentration of citric acid was 20 mol·L^(-1),under which the degradation percentages of FLU,PHE,FLA and PYR were 81%,78%,60%,and 100%,respectively.And PAHs can be completely degraded after further extension of time.In addition,the Fenton oxidation technology had the best degradation effect on PAHs below 0.1 mg·L^(-1) in water,and the degradation percentage of four PAHs exceeded 94%.This study had shown that the optimal parameters of Fe^(2+)/H_(2)O_(2) addition ratio,citric acid concentration,reaction time,H_(2)O_(2) concentration and po

关 键 词：多环芳烃(PAHs) FENTON氧化技术 柠檬酸 反应时间 降解 

分 类 号：X703[环境科学与工程—环境工程]