摘要
以抗新型冠状肺炎药物——磷酸氯喹(CQP)为研究对象,考察其在紫外活化过硫酸盐体系(UV/PS)中的降解效果.通过竞争动力学实验,确定了CQP与羟基自由基(HO·)和硫酸根自由基(SO_(4)^(-)·)的二级反应速率常数,同时考察了PS浓度、pH和常见无机阴离子对UV/PS体系中CQP降解的影响,并通过建立动力学模型预测CQP浓度和主要自由基浓度以探究其影响机制.结果表明,UV/PS体系对CQP的降解效果显著优于单一UV、单一太阳光或单一PS体系,在10 min内可降解91.3%的CQP;在pH为6.9的条件下,CQP与HO·和SO_(4)^(-)·的二级反应速率常数分别为8.9×10^(9)L·(mol·s)^(-1)和1.4×10^(10)L·(mol·s)^(-1),其中SO_(4)^(-)·是主要活性物种;CQP的降解速率随PS浓度增加而增大,HCO_(3)^(-)和Cl^(-)的加入对UV/PS体系中CQP的去除起到抑制作用,碱性较强的条件不利于CQP的转化.经LC-MS分析,发现CQP在UV/PS体系中主要经过N-脱乙基化、C—N键断裂和抽氢等反应被逐步降解为其他有机中间产物.加大PS浓度和pH可提高其矿化率.此研究可为抗新冠肺炎医药废水的处理提供帮助.
The degradation of chloroquine phosphate(CQP),an anti-COVID-19 drug,was investigated in a UV-activated persulfate system(UV/PS).The second-order rate constants of CQP with hydroxyl radicals(HO·)and sulfate radicals(SO_(4)^(-)·)were determined using a competition kinetics experiment,and the effects of persulfate concentration,pH,and inorganic anions on the degradation of CQP were also systematically studied.Furthermore,a kinetic model was established to predict the concentration of CQP and major free radicals to explore its mechanism of influence.The results showed that the degradation efficiency of CQP could reach 91.3%after 10 min under UV/PS,which was significantly higher than that under UV,sunlight,or PS alone.At pH=6.9,the second-order rate reaction constants of CQP with HO·and SO_(4)^(-)·were 8.9×10^(9)L·(mol·s)^(-1)and 1.4×10^(10)L·(mol·s)^(-1),respectively,and the main active species was SO_(4)^(-)·.The degradation rate of CQP increased with increasing concentrations of PS and decreased with the addition of HCO_(3)^(-)and Cl^(-).The removal efficiency of CQP was inhibited under stronger alkaline conditions.N-de-ethylation,cleavage of the C—N bond,and hydrogen abstraction were proposed as the principal pathways of CQP degradation based on LC-MS analysis.The mineralization rate of CQP could be improved by increasing PS concentration and pH values.This study could be helpful for the treatment of anti-COVID-19 pharmaceutical wastewater.
作者
李阳
许玻珲
邓琳
罗伟
LI Yang;XU Bo-hui;DENG Lin;LUO Wei(School of Civil Engineering,Southeast University,Nanjing 211189,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2022年第9期4597-4607,共11页
Environmental Science
基金
国家自然科学基金项目(21677032,22076023)。
关键词
紫外
过硫酸盐
磷酸氯喹
动力学模型
高级氧化
ultraviolet
persulfate
chloroquine phosphate
kinetic modeling
advanced oxidation