摘要
含卤阻燃剂广泛应用于各类电子产品的生产,难降解且具有生物毒性.在生产和使用过程中,部分含卤阻燃剂会残留在水体并排放到水环境造成累积污染,威胁水环境安全,亟需探寻有效的降解去毒方法.本研究通过Gaussian与ECOSAR模型预测了四氯双酚A(TCBPA)、四溴双酚A(TBBPA)、十溴二苯乙烷(DBDPE)等3种典型含卤阻燃剂在紫外/次氯酸(UV/Cl)体系中的光催氧化降解路径与产物毒性.结果表明,UV/Cl体系中的含氯自由基(RCS)与羟基自由基(·OH)易攻击阻燃剂分子结构上键能较低、Fukui指数较高的位点,促使C—Cl键、C—Br键、C—C键等因为受到攻击而断裂,进而降解阻燃剂.同时,利用ECOSAR模型评估发现降解产物的急性毒性LC_(50)-96 h均低于100 mg·L^(-1),佐证了UV/Cl体系对含卤阻燃剂降解的有效性,并降低其环境危害.因此,采用Gaussian计算、ECOSAR模型相结合的分析方法,能够更加便捷地预测阻燃剂降解路径与产物毒性特征,为深入揭示UV/Cl体系光催氧化降解含卤阻燃剂机理提供新思路.
Halogen-containing flame retardants are extensively used in the production of various electronic products,which will inevitably be discharged into surface water,causing cumulative pollution,and threatening the safety of the aquatic environment for their persistent stability and biological toxicity.Thus,it is urgent to explore effective degradation and detoxification methods.In this study,the Gaussian and ECOSAR models were employed to predict the performance of three typical halogen-containing flame retardants including TCBPA(tetrachlorobisphenol A),TBBPA(tetrabromobisphenol A),and DBDPE(decabromodiphenylethane)in ultraviolet excited hypochlorous acid(UV/Cl)systems for evaluating their photocatalytic oxidation degradation pathways and products toxicity.The results showed that the chlorine-containing radicals(RCS)and hydroxyl radicals(·OH)in the UV/Cl system were prone to attack the sites with lower bond energy and higher Fukui index on the molecular structure of the flame retardant,which promoted the degradation of flame retardants through the cleavage of C—Cl Bonds,C—Br bonds,C—C bonds,etc.Meanwhile,the ECOSAR model was used to evaluate the acute toxicity LC_(50)-96 h of the degradation products,which were all lower than 100 mg·L^(-1),and proved the effectiveness of halogen-containing flame retardants in the UV/Cl process and reduced their environmental hazards.Therefore,the combined analysis method of Gaussian calculation and ECOSAR model conveniently predicted the degradation path and product toxicity characteristics of flame retardants,and provided new insights into further revealing the mechanism of photocatalytic oxidation degradation of halogen-containing flame retardants in UV/Cl system.
作者
卢志磊
范勇杰
陈洁洁
杨婧
吴春山
孙启元
LU Zhilei;FAN Yongjie;CHEN Jiejie;YANG Jing;WU Chunshan;SUN Qiyuan(College of Environmental Science and Engineering,Fujian Normal University,Fuzhou,350007,China;Fujian Provincial Key Laboratory of Pollution Control and Resource Recycling,Fuzhou,350007,China;Fujian College and University Engineering Research Center for Municipal Waste Resourceization and Management,Fuzhou,350007,China)
出处
《环境化学》
CAS
CSCD
北大核心
2024年第1期82-91,共10页
Environmental Chemistry
基金
国家自然科学基金(52070044)
福建省自然科学基金(2021J06022)资助。
