光照射下微塑料上环境持久性自由基的形成,Environmental Science & Technology

当前位置： X-MOL 学术 › Environ. Sci. Technol. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

光照射下微塑料上环境持久性自由基的形成
Environmental Science & Technology ( IF 10.8 ) Pub Date : 2019-06-27 , DOI: 10.1021/acs.est.9b01474
Kecheng Zhu ₁ , Hanzhong Jia ₁ , Song Zhao ₁ , Tianjiao Xia ₁ , Xuetao Guo ₁ , Tiecheng Wang ₁ , Lingyan Zhu _{1,

2}

Affiliation

据推测，微塑料（MPs）在环境条件下的老化过程中是惰性的。在这项研究中，在模拟太阳光照射下老化了四种原始MP，包括聚苯乙烯（PS），酚醛树脂（PF），聚乙烯（PE）和聚氯乙烯（PVC）。出乎意料的是，通过电子顺磁共振（EPR）光谱在被辐照的PS和PF而非PE和PVC上检测到了几种环境持久性自由基（EPFR），这些自由基被认为是一种新兴污染物。根据光老化时间的长短，在PS和PF上生成的EPFR的特征性g因子分别为2.0044–2.0049和2.0043–2.0044。PS和PF上生成的EPFR在初始阶段迅速衰减，然后随着经过的老化时间而缓慢消失。₂ / H ₂ O的添加，在光照射下形成EPFR。伴随着EPFR的形成，还观察到了活性氧，例如O ₂^•和O。这些发现为评估国会议员对生物和生态系统的潜在危害提供了新颖的见解。

"点击查看英文标题和摘要"

Formation of Environmentally Persistent Free Radicals on Microplastics under Light Irradiation

Microplastics (MPs) are presumed to be inert during aging under ambient conditions. In this study, four types of virgin MPs, including polystyrene (PS), phenol-formaldehyde resin (PF), polyethylene (PE), and polyvinyl chloride (PVC), were aged under simulated solar light irradiation. Surprisingly, several environmentally persistent free radicals (EPFRs), which are considered to be a type of emerging contaminant, were detected on the irradiated PS and PF, rather than PE and PVC, by electron paramagnetic resonance (EPR) spectroscopy. Depending on the photoaging duration time, the characteristic g-factors of the EPFRs produced on PS and PF were 2.0044–2.0049 and 2.0043–2.0044, respectively. The generated EPFRs on PS and PF decayed rapidly at the initial stage and then slowly disappeared with the elapsed aging time. Analyses by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC) suggested that MPs might experience chemical chain scission, O₂/H₂O addition, and EPFR formation under the light irradiation. Accompanying with the formation of EPFRs, reactive oxygen species, such as O₂^•– and •OH, were also observed. The findings provide a novel insight to evaluate the potential hazards of MPs to organisms and ecosystems.

更新日期：2019-06-29

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南