摘要
电芬顿技术是水体中难降解污染物的高效处理方法之一,然而,该体系中的H_(2)O_(2)存在运输不便的缺陷。以磷酸三乙酯(TEP)为目标污染物,以过氧化钙(CP)为氧化剂,以铁片作为腐蚀阳极和铁源,构建了基于过氧化钙的类电芬顿体系(电-Fe-CP体系),并考察了该体系对TEP的矿化效能及其影响因素,通过CP释放H_(2)O_(2)试验和淬灭试验探讨了电-Fe-CP体系矿化TEP的机理,最后对反应产物在不同pH下形成的沉淀物进行了扫描电镜(SEM)、能量色散光谱(EDS)、X射线粉末衍射(XRD)和傅里叶变换红外光谱(FTIR)表征。结果表明:在初始pH为2.5,TEP和CP浓度分别为20 mg/L和4 mmol/L,Fe片大小为20 mm×40 mm×1 mm,电流密度为2.50 A/m^(2)的条件下,电-Fe-CP体系在20 min内对TEP的矿化率可达到94.6%,且水中的Cl^(-)、NO_(3)^(-)、HCO_(3)^(-)等无机阴离子共存对体系矿化效果影响较小。电-Fe-CP体系中主要活性物种为羟基自由基。此外,pH对反应生成的沉淀物组分有较大影响,其中pH为8.5时形成的沉淀物主要为氢氧化铁、硫酸钙和磷酸钙,pH为10.5时可能还存在少量羟基磷灰石。研究证实了利用基于电-Fe-CP体系矿化水中TEP的可行性,并提出电-Fe-CP体系可能的应用场景及应用建议。
Electro-Fenton Technology is an effective process for the treatment of refractory contaminants in wastewater.Howerver,the technolgy has the defect of inconvenient transportation for H_(2)O_(2).In this study,by selecting triethyl phosphate esters(TEP)as the target pollutant and calcium peroxide(CP)as the oxidant,with iron plate as the corrosion anode and iron source,a CP-based electro-Fenton-like system(electro-Fe-CP system)was firstly constructed to investigate its mineralization efficiency of TEP and its affecting factors.The mechanisms of TEP mineralization in the electro-Fe-CP system were then explored via the release trials of H_(2)O_(2)by CP and the quenching experiments.At last,the precipitates formed from the reaction product at different pH values were characterized by scanning electron microscope(SEM),energy-dispersive spectrometry(EDS),X-ray diffractometer(XRD)and Fourier transform infrared(FTIR)spectra.The results showed that when initial pH,the concentration of TEP,the concentration of CP,the size of Fe plate and the current density were 2.5,20 mg/L,4 mmol/L,20 mm×40 mm×1 mm,and 2.50 A/m^(2),respectively,the electro-Fe-CP system achieved a mineralization rate of 94.6% within 20 min.In addition,inorganic anions(Cl^(-),NO_(3)^(-),HCO_(3)^(-))had a minor influence on the mineralization of TEP.Quenching experiments indicated that hydroxyl radicals(·OH)were the major active species in the electro-Fe-CP system.Furthermore,the pH significantly affected the composition of the precipitate formed from the reaction products.Specifically,the precipitate at pH 8.5 mainly consisted of iron hydroxide,calcium sulfate,and calcium phosphate,while it might also contain a small amount of hydroxyapatite at pH 10.5.This study confirms the feasibility of utilizing electro-Fenton-like system based on calcium peroxide for treating TEP in water.The possible application scenarios and suggestions for the electro-Fe-CP system were also proposed.
作者
崔泉涛
刘瑜
王楷
严素定
CUI Quantao;LIU Yu;WANG Kai;YAN Suding(College of Urban and Environmental Sciences,Hubei Normal University;Huangshi Key Laboratory of Prevention and Control of Soil Pollution)
出处
《环境工程技术学报》
北大核心
2025年第3期955-964,共10页
Journal of Environmental Engineering Technology
基金
国家自然科学基金项目(22378104)
湖北省自然科学基金项目(2022CFB504)。
关键词
磷酸三乙酯(TEP)
铁片
过氧化钙
类电芬顿
矿化
triethyl phosphate esters(TEP)
iron sheet
calcium peroxide
electro-Fenton-like
mineralization
