A new point to correlate the multi-dimensional assessment for the aging process of microfibers

Jiangpeng Li; Lijuan Wang; Zhe Xu; Jianshuai Zhang; Jiawei Li; Xiao Lu; Ruoqun Yan; Yuanyuan Tang

doi:10.1016/j.watres.2023.119933

A new point to correlate the multi-dimensional assessment for the aging process of microfibers

Water Res. 2023 May 15:235:119933. doi: 10.1016/j.watres.2023.119933. Epub 2023 Mar 30.

Authors

Jiangpeng Li¹, Lijuan Wang¹, Zhe Xu², Jianshuai Zhang¹, Jiawei Li¹, Xiao Lu¹, Ruoqun Yan¹, Yuanyuan Tang³

Affiliations

¹ State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China.
² State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China; Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, PR China.
³ State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China. Electronic address: tangyy@sustech.edu.cn.

PMID: 37023644
DOI: 10.1016/j.watres.2023.119933

Abstract

Fiber, the most prevalent plastic type, can be weathered and eroded easily in the natural environment. Although a variety of techniques have been applied to characterize the aging characteristics of plastics, a comprehensive understanding was critically essential to correlate the multi-dimensional assessment of the weathering process of microfibers and their environmental behavior. Therefore, in this study, microfibers were prepared from the face masks and Pb²⁺ was selected as a typical metal pollutant. The weathering process was simulated by xenon aging and chemical aging, and then subjected to Pb²⁺adsorption to examine the effect of weathering processes. The changes in fiber property and structure were detected by using various characterization techniques, with the development of several aging indices to quantify the changes. The two-dimensional Fourier transform infrared correlation spectroscopy analysis (2D-FTIR-COS) and Raman mapping were also performed to understand the order of changes in the surface functional groups of the fiber. The results showed that both aging processes altered the surface morphology, physicochemical properties, and polypropylene chain conformations of the microfibers, with stronger effect after chemical aging. The aging process also enhanced the affinity of microfiber to Pb²⁺. Moreover, the changes and correlation of the aging indices were analyzed, showing that the maximum adsorption capacity (Q_max) was positively related to carbonyl index (CI), oxygen-to-carbon atom (O/C) ratio and intensity ratio of the Raman peaks (I_841/808), but negatively related to contact angle and the temperature at the maximum weight loss rate (T_m). The O/C ratio was more suitable to quantify the surface changes with lower aging degree while the CI value explained the chemical aging process better. Overall, this study discussed the weathering processes of microfibers based on a multi-dimensional investigation, and attempted to correlate the aging characteristics of the microfibers and their environmental behavior.

Keywords: Adsorption; Aging; Correlation; Face masks; Microfibers; Quantitative.

MeSH terms

Environmental Pollutants* / analysis
Lead
Plastics
Polypropylenes
Temperature
Water Pollutants, Chemical* / chemistry

Substances

Lead
Plastics
Polypropylenes
Environmental Pollutants
Water Pollutants, Chemical