亚硫酸氢盐强化微量Fe^(2+)活化过二硫酸盐降解扑热息痛  

Bisulfite Promoted Minute Fe^(2+)-Activated Peroxydisulfate for Paracetamol Degradation

作　　者：莫茜婷 聂淑华 晏彩霞 丁明军[1] 陈诗瑶 聂明华 MO Xi-ting;NIE Shu-hua;YAN Cai-xia;DING Ming-jun;CHEN Shi-yao;NIE Ming-hua(Key Laboratory of Poyang Lake Wetland and Watershed Research,Ministry of Education,School of Geography and Environment,Jiangxi Normal University,Nanchang 330022,China;Jiangxi Drug Inspection Center,Nanchang 330029,China;Key Laboratory of Eco-Geochemistry,Ministry of Natural Resource,Beijing 100037,China)

机构地区：[1]江西师范大学地理与环境学院,鄱阳湖湿地与流域研究教育部重点实验室,南昌330022 [2]江西省药品检查员中心,南昌330029 [3]自然资源部生态地球化学重点实验室,北京100037

出　　处：《环境科学》2023年第12期6790-6800,共11页Environmental Science

基　　金：国家自然科学基金项目(42067034,42067058);江西省主要学科学术和技术带头人培养计划项目(20212BCJL23058);江西省杰出青年基金项目(20232ACB213014);江西省自然科学基金项目(20232BAB203083)。

摘　　要：Fe^(2+)可激活过二硫酸盐(PDS)快速产生硫酸根自由基(SO_(4)^(-)·),但Fe^(2+)会快速转化为低活性的Fe^(3+),且Fe^(2+)的投加量普遍较大,限制了该体系的广泛应用.采用亚硫酸氢盐(BS)强化微量Fe^(2+)-PDS体系降解水中的扑热息痛(APAP).结果表明,投加BS可促进Fe^(2+)-Fe^(3+)的循环,明显改善Fe^(2+)-PDS体系对APAP的降解效果,在最优条件下(PDS=0.6 mmol·L^(-1);BS=0.4 mmol·L^(-1);Fe^(2+)=10μmol·L^(-1);pH=4)下,APAP(4μmol·L^(-1))可在180 s内被完全降解.同时,APAP的降解速率随BS(0~0.6 mmol·L^(-1))和PDS(0.2~1.5 mmol·L^(-1))浓度的增大而升高,适量提高Fe^(2+)浓度可促进APAP的降解,但增加BS的投加次数对降解速率影响不大.HCO_(3)^(-)与HPO_(4)^(2-)明显抑制了体系降解APAP的效率,Cl^(-)和NO_(3)^(-)有轻微抑制作用,腐殖酸(HA)则影响不大.通过淬灭实验和电子顺磁共振波谱检测,证实了体系中SO_(4)^(-)·、·OH和单线态氧的产生,其中SO_(4)^(-)·是降解APAP的主要活性物种.利用三维荧光光谱技术对APAP降解过程进行了表征,表明APAP降解产物具有荧光特性.此外,还鉴定出5种中间产物,并提出了3种可能的降解途径.体系在实际水体中的效能低于超纯水中的表现,但延长反应时间可明显增强降解效果,表明BS-Fe^(2+)-PDS体系是一种有前景的有机污染物降解方法.Fe^(2+)has been commonly selected to activate peroxydisulfate(PDS)for sulfate radical(SO_(4)^(-)·)generation because of its eco-friendly,cost-effective,and high activity characteristics.However,Fe^(2+)can be rapidly oxidized to Fe^(3+)in the reaction,leading to poor utilization of iron for PDS activation.Further,a fairly high concentration of Fe^(2+)is generally required and may cause iron sludge production and secondary pollution.In this study,a minute Fe^(2+)-activated PDS system induced by bisulfite(BS)was used to degrade paracetamol(APAP)in water.The results showed that the Fe^(2+)-PDS system could be enhanced by the circulation of Fe^(2+)-Fe^(3+)with the injection of BS and by keeping Fe^(2+)at a high concentration.Under the optimal conditions(PDS=0.6 mol·L^(-1);BS=0.4 mol·L^(-1);Fe^(2+)=10μmol·L^(-1);pH=4),100% APAP(4μmol·L^(-1))was removed within 180 s.The degradation rate of APAP increased with the increase in BS(0-0.6 mmol·L^(-1))and PDS(0.2-1.5 mmol·L^(-1))concentration,and a modest Fe^(2+)concentration could accelerate APAP removal.Co-existing substances inhibited the APAP removal and followed the order of HCO_(3)^(-)>HPO_(4)^(2-)>Cl^(-)>NO_(3)^(-)>humic acid(HA).Based on the quenching experiments and electron paramagnetic resonance spectroscopy test,SO_(4)^(-)·was shown to be the primary reactive species for APAP decomposition in the BS-Fe^(2+)-PDS process.Three-dimensional fluorescence spectroscopy revealed that APAP intermediates had fluorescence characteristics.Moreover,five intermediates were identified,and the probable APAP degradation pathways were proposed.The removal efficiencies of APAP were lower in real waters than that in ultrapure water.Nevertheless,the removal effect was greatly improved after a prolonged reaction time.All results indicated that the BS-Fe^(2+)-PDS system could be a promising method for organic pollutant treatment.

关 键 词：硫酸根自由基(SO_(4)^(-)·) 亚硫酸氢盐 扑热息痛 微量Fe^(2+) 降解 过二硫酸盐(PDS) 

分 类 号：X131.2[环境科学与工程—环境科学]