摘要
作为一种具有吸附能力的新型污染物,微塑料对环境中污染物的吸附作用会加剧其对环境的污染。该文通过紫外灯照射120 d对聚乙烯(PE)、聚苯乙烯(PS)和聚氯乙烯(PVC)3种微塑料进行老化处理,研究老化作用对微塑料吸附水土环境中磷的影响。结果表明,老化过程使微塑料表面出现大量褶皱、碎片和沟壑,比表面积增大,含氧官能团数量显著增加。相比于原始塑料,老化微塑料对磷的吸附量均有所增加,由此说明老化过程提高了微塑料的吸附能力。老化前后微塑料对磷吸附行为均较好地符合准二级动力学模型(R^(2)>0.964),表明老化前后微塑料对磷的吸附是以化学吸附为主。老化前后的微塑料更符合Langmuir等温吸附模型(R^(2)>0.961),表明磷在各微塑料上吸附以单层吸附为主。p H对微塑料吸附磷影响显著,老化前后的微塑料随pH的增加对磷的单位吸附量均呈“U型”趋势,且老化后微塑料的吸附量均高于老化前。在pH为9时老化PE、PS、PVC对磷的吸附量达到最大,分别为0.752、0.758、0.896 mg/g。随土壤中微塑料添加比例的增大,土壤-微塑料体系对磷的吸附量提升有限;相较于添加原始微塑料的土壤-微塑料体系,添加同等量老化微塑料的体系对磷的吸附量提升不显著,且不会因为微塑料的种类不同而产生显著差异。
As a new type of pollutant with adsorption capacity,the adsorption of microplastics to pollutants in the environment can aggravate their environmental pollution.Three microplastics,polyethylene(PE),polystyrene(PS),and polyvinyl chloride(PVC)were aged by UV irradiation for 120 days to investigate the effect of aging on adsorption of phosohorus by microplastics in water and soil environments.The results showed that the aging process caused a large number of folds,fragments,and grooves on the surface of microplastics,and significantly increased their specific surface area and the number of oxygen-containing functional groups.Compared with the original plastic,phosphorus adsorption capacity of aged microplastics increased,indicating that the aging process improved the adsorption capacity of microplastics.The phosphorus adsorption behavior of microplastics before and after aging conforms to the quasi-secondary kinetic model(R^(2)>0.964),which indicated that the phosphorus adsorption on microplastics before and after aging was mainly chemisorption.The microplastics before and after aging were more consistent with the Langmuir isothermal adsorption model(R^(2)>0.964),which indicated that the phosphorus adsorption on each microplastic was mainly monolayer adsorption.The effect of pH on phosphorus adsorption on microplastics was significant.The unit phosphorus adsorption amount of unit microplastics before and after aging showed a‘U-shaped’trend with increasing pH,and the adsorption amount of microplastics after aging was higher than that before aging.The phosphorus adsorption capacity of the soil microplastic system increased with the increase of the percentage of microplastics added to the soil,but it was limited.The phosphorus sorption capacity of the soil microplastic system was increased but limited,compared with the phosphorus sorption capacity of the original microplastic aging microplastic,but not significantly,and did not differ significantly according to the type of microplastic.
作者
崔佳惠
高良敏
张金昕
金鑫诚
吴宇帆
袁梦航
陆寒松
魏飞燕
CUI Jiahui;GAO Liangmin;ZHANG Jinxin;JIN Xincheng;WU Yufan;YUAN Menghang;LU Hansong;WEI Feiyan(School of Earth and Environment,Anhui University of Technology,Huainan 232000,China)
出处
《环境科学与技术》
CAS
CSCD
北大核心
2023年第9期68-76,共9页
Environmental Science & Technology
基金
安徽省重点研究与开发计划项目生态环境专项(202004i07020012)
关键词
微塑料
磷
吸附
老化
microplastics
phosphorus
adsorption
aging
作者简介
崔佳惠(1999-),女,硕士研究生,研究方向为水污染控制及治理,(电子信箱)2283913995@qq.com;通讯作者:高良敏,男,教授,博士,(电子信箱)gaolmin@163.com。
