The scientific research team led by Prof. Jia Hanzhong from the College of Natural Resources and Environment Has Made New Progress in the Field of Photoaging for Micro Plastics
Recently, the scientific research team led by Prof. Jia Hanzhong from the College of Natural Resources and Environment, Northwest A&F University has made great progress in the research on the effect of inorganic anions on the photoaging of polystyrene microplastics (PS-MP) in water and its light conversion mechanism, which was published in Water Research under the title of "Inorganic Anions Influenced the Photoaging Kinetics and Mechanism of Polycrystalline Microplastic under the Simulated Sunlight: Role of Reactive Radio Specialties". Associate Prof. Zhu Kecheng from the College of Natural Resources and Environment acts as the first author, and Prof. Jia Hanzhong is the corresponding author of the paper.
PS-MP is the most common and representative micro plastic in water environment. When PS-MP is exposed to sunlight, it will age. The physical and chemical properties of PS-MP will change significantly, which affects its environmental behavior and risk. A variety of inorganic anions (HCO3−, NO3−, Cl−, Br−) in water may interact with PS-MP during photoaging and affect the aging process and mechanism of PS-MP. However, it’s not clear that the photoaging kinetics and mechanism of the effects of these components on MPs.
Prof. Jia Hanzhong's team has been engaged in the research on the environmental effects and free radical process of micro plastics for a long time. In the previous research, it was found that micro plastics will form a new class of environmental risk substances - persistent free radicals and reactive oxygen species during the photoaging process. Based on the previous work, the team adopted the method of simulating sunlight aging, focused on exploring the effects of various anions (HCO3−, NO3−, Cl−, Br−) in natural water on PS-MP photoaging, and conducted a detailed analysis on particle size, oxygen-containing functional groups, aging degree, molecular weight and molecular structure during PS-MP photoaging. The formation of active oxygen, active halogen radical and carbonate radical in different anion reaction systems was confirmed. The role of active oxygen and other active radicals in PS-MP photoaging process was clarified through quenching test, and the mechanism of anions affecting PS-MP photoaging process was clarified. This study provides important information for the photoaging behavior and potential ecological risk of microplastics in the environment.
The research was supported by the National Natural Science Foundation of China.
Article link: https://doi.org/10.1016/j.watres.2022.118294.
