摘要
微塑料在水环境中会吸附共存条件下同为新兴污染物的抗生素,并作为抗生素载体与其一同迁移,而微塑料自身的老化和周围环境条件是影响吸附能力的重要原因。该文以聚苯乙烯(PS)颗粒为代表,在不同环境介质下用紫外照射模拟微塑料在环境中的光老化,研究了老化前后微塑料对盐酸环丙沙星(CIP)的吸附行为,并探究了离子强度、pH值和溶解性有机质(DOM)对PS吸附性能的影响以及相关机制。结果表明:紫外线老化使PS微塑料粒径减小,表面出现沟壑、褶皱以及剥落现象,羰基指数增高。原始和老化PS吸附CIP的过程均符合准二级动力学模型,Langmuir和Freundlich等温吸附模型均能较好地拟合原始和在空气中老化PS对CIP的吸附过程,而在水中老化的PS对CIP的吸附更符合以非均质多分子层吸附反应为主的Freundlich等温吸附模型。老化PS对CIP的吸附量明显高于原始PS,且水老化PS吸附效果优于空气老化,同时,离子强度、pH、溶解性有机质对微塑料的吸附能力影响也很大。
As emerging pollutants,microplastics can adsorb antibiotics in water environments under coexistence conditions,and migrate together as carriers.The aging of microplastics and surrounding environmental conditions are important factors af⁃fecting the adsorption capacity of microplastics.Polystyrene(PS)particles,one of the typical microplastics was chosen in this study.Photo-aging of microplastics in different environmental media was simulated using ultraviolet(UV)radiation.As probe sorbates,the sorption behaviors of ciprofloxacin(CIP)on original and aged PS in aqueous solution were investigated,and the effects of ionic strength,pH value,and dissolved organic matter(DOM)on the adsorption capacity of PS as well as the related theory were discussed.The results showed that the particle size of PS microplastics had reduced,and many wrinkles,fragments and grooves appeared in the surface of aged microplastics after UV radiation.At the same time,the specific surface area and the carbonyl index increased.The pseudo-second-order kinetic models to describe the adsorption process of the original and aged PS were more reasonable.Both Langmuir and Freundlich models provided a better fit of the data which CIP on original PS and air-aged PS in air,while the CIP on water-aged PS conformed more to the Freundlich model,which was based on the adsorption reaction of non-homogeneous multilayer molecules.Data analysis indicated that the aged microplas⁃tics had higher adsorption capacity of CIP than original ones,and the adsorption effect of water-aged PS is better than that of air-aged PS.Meanwhile,ionic strength,pH value and DOM were also showed great influence to the adsorption behavior of microplastics.
作者
林雨男
阎波
侯春壹
孙博文
LIN Yunan;YAN Bo;HOU Chunyi;SUN Bowen(College of Marine and Environmental Science,Tianjin University of Science and Technology,Tianjin 300457,China)
出处
《环境科学与技术》
CAS
CSCD
北大核心
2024年第10期46-57,共12页
Environmental Science & Technology
基金
国家级大学生创新创业训练计划项目(202210057028)。
关键词
微塑料
盐酸环丙沙星
吸附行为
老化
环境因素
microplastics
ciprofloxacin hydrochloride
adsorption behavior
aging
environmental factors
