摘要
唑类抗真菌剂广泛应用于药物和个人护理品(pharmaceutical and personal care products,PPCPs)中,常规污水处理工艺难以将其有效去除.大量唑类抗真菌剂排入受纳环境后会对生态系统造成一系列负面影响.为了解唑类抗真菌剂的臭氧氧化降解过程和机理,以氯咪巴唑(climbazole,CZ)为例,通过设置不同条件的对比试验,系统研究CZ在臭氧氧化过程中的影响因素及其去除规律,同时采用超高效液相色谱-飞行时间质谱联用仪UPLC-Q/TOF对其降解产物进行鉴定.影响因素试验结果表明:①CZ起始浓度由1.0 mg/L增至4.0 mg/L时,臭氧氧化20 min下CZ的降解率从99.1%降至69.3%;②反应体系起始pH由5.0升至9.0时,CZ臭氧降解半衰期由1.38 min延长至7.18 min;③臭氧流速由0.1 L/min增至0.4 L/min时,臭氧氧化20 min时CZ的降解率从66.5%提至99.4%,但臭氧流速超过0.3 L/min以后,CZ降解率的增幅较小;④自然水体及其高浓度共存组分(碳酸氢根和腐殖酸)均会明显抑制CZ的臭氧氧化反应速率,CZ降解半衰期大多数超过6 min(空白对照组为1.99 min).因此,在臭氧氧化降解新兴有机污染物或对臭氧氧化工艺进行优化时,应充分考虑起始污染负荷、pH、臭氧流速、水体水质状况等对处理效果的影响.产物鉴定结果表明:臭氧氧化反应可将CZ碎裂重组形成两个主要降解产物——TP269和TP297,二者的产率分别为11.45%和8.90%.研究显示,起始污染负荷、pH、臭氧流速、水体水质状况均会明显影响CZ的臭氧降解效果;两个CZ臭氧降解产物的产率虽不高,但其毒性有待进一步研究.
Azole antifungals are widely used in pharmaceutical and personal care products(PPCPs),and they are difficult to be removed by conventional wastewater treatment processes.A large amount of azole antifungals discharged into the receiving environment may cause a series of negative effects.In order to understand the degradation kinetics and mechanism of azole antifungals by ozonation,climbazole(CZ)was selected as the target compound,the influencing factors and removal law were systematically studied through setting comparative experiments under different ozonation conditions,and the degradation products were identified by UPLC-Q/TOF.The results showed that:(1)When the initial CZ concentration increased from 1.0 mg/L to 4.0 mg/L,the degradation of CZ at 20 min ozonatio decreased from 99.1%to 69.3%.(2)The half-lives of CZ degradation by ozone increased from 1.38 min to 7.18 min with the increase of the initial pH from 5.0 to 9.0.(3)The degradation of CZ at 20 min ozonation increased from 66.5%to 99.4%when the ozone flow rate increased from 0.1 L/min to 0.4 L/min,but it increased very slow when the ozone flow rate exceeded 0.3 L/min.(4)Natural water and its coexisting components(high concentration of bicarbonate radical and humic acid)showed significant inhibition effects on the degradation of CZ in ozonation process,where the degradation half-lives of CZ were more than 6 min(1.99 min for blank controller)in most cases.Therefore,the influence factors such as initial pollution load,pH value,ozone flow rate and water quality should be considered when using ozonation as a treatment technology to remove emerging organic pollutants.Two main CZ degradation products(TP269 and TP297)were formed through fracturing and restructuring in the ozonation treatment,with the products yields of 11.45%and 8.90%,respectively.Above results reveals that ozone degradation effect of CZ can be influence obviously by initial pollution load,pH value,ozone flow rate and water quality etc.The yields of two CZ degradation products were very low,but their toxicity needs to be studied.
作者
宋江燕
李方鸿
吴根义
胡嘉梧
佘磊
刘有胜
柳王荣
SONG Jiangyan;LI Fanghong;WU Genyi;HU Jiawu;SHE Lei;LIU Yousheng;LIU Wangrong(State Environmental Protection Key Laboratory of Water Environmental Simulation and Pollution Control,South China Institute of Environmental Sciences,Ministry of Ecology and Environment,Guangzhou 510530,China;College of Resources and Environment,Hunan Agricultural University,Changsha 410128,China;Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety,School of Environment,South China Normal University,Guangzhou 510006,China)
出处
《环境科学研究》
CAS
CSCD
北大核心
2022年第2期478-487,共10页
Research of Environmental Sciences
基金
广东省自然科学基金项目(No.2018A030310681)
广东省科技计划项目(No.2019B030301008)。
关键词
臭氧氧化
氯咪巴唑
影响因素
降解率
半衰期
降解产物
ozonation
climbazole
influencing factors
degradation rate
half-life
degradation products