摘要
以污水中检出频率较高的磺胺吡啶(SPD)为目标化合物,探究了HCO_(3)^(-)对紫外/过硫酸盐(UV/PMS)体系中SPD降解的影响,详细探讨了HCO_(3)^(-)浓度､pH值､SPD浓度和溶解有机质(DOM)对SPD降解的影响.通过构建自由基动力学模型,探明不同环境条件下CO_(3)^(-•)对SPD降解的影响及贡献.研究发现,NaHCO_(3)的加入促进了SPD的降解,表观降解速率常数(k)增加了1倍;随着溶液初始pH值增加(5~8),SPD的k值提高了约3倍;随着SPD初始浓度(5~25μmol/L)和HA(0~20mg C/L)的增加,k值分别下降了约81%､84%.构建的自由基动力学模型可较好的预测不同水基质中UV/PMS氧化降解SPD的速率常数,误差范围0.44%~5.53%;该模型表明CO_(3)^(-•)在SPD的UV/PMS氧化降解中起到不可忽视的作用,随着HCO_(3)^(-)浓度和pH值的增加其贡献逐渐增强,最高可达34%;随着SPD初始浓度和HA浓度增加,其贡献由34%分别逐渐下降至9%和17%.
Take sulfapyridine(SPD),which is detected frequently in sewage,as the target compound to explore the effect of HCO_(3)-on the degradation of SPD in the UV/PMS system,and discussed the effects of HCO_(3)-concentration,pH,SPD concentration and dissolved organic matter(DOM)on the degradation of SPD in detail.By constructing a free radical kinetic model,the influence and contributions of CO_(3)^(-•)on the degradation of SPD under different environmental conditions were explored.It was found that the addition of NaHCO3 promoted the degradation of SPD,and the apparent degradation rate constant(k)doubled;and with the initial pH value of the solution increasing(5~8),the k value of SPD increased by about 3times;and with the initial concentration of SPD(5~25μmol/L)and the increase of HA(0~20mg C/L),so k value decreased by about 81%and 84%respectively.The constructed free radical kinetic model could better predict the rate constant of UV/PMS oxidative degradation of SPD in different water substrates,with an error range of 0.44%~5.53%.The model showed that CO_(3)^(-•)played an important role in the UV/PMS oxidative degradation of SPD,and its contribution gradually increased with the increase of HCO_(3)-concentration and pH,upped to 34%.With the increase of the initial concentration of SPD and the concentration of HA,their contributions gradually decreased from 34%to 9%and 17%respectively.
作者
周碟
刘华英
汪念
张倓
屠依娜
李英杰
ZHOU Die;LIU Hua-ying;WANG Nian;ZHANG Tan;TU Yi-na;LI Ying-jie(Faculty of Environmental Science and Engineering,Kunming University of Science and Technology,Kunming 650500,China;Faculty of Chemical Engineering,Kunming University of Science and Technology,Kunming 650500,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2023年第9期4585-4595,共11页
China Environmental Science
基金
国家自然科学基金资助项目(22266020)。
