Rapid capture of perfluorooctanoic acid and perfluorooctane sulfonate at environmentally relevant concentrations via the 'mesh trap' of triazine-based polymer network: Mechanism and photocatalytic regeneration

Boru Gao; Lairong Wu; Shaokang Li; Jinjin Yang; Mengmeng Dou; Genwang Chang; Xiang Li

doi:10.1016/j.jhazmat.2024.136698

Rapid capture of perfluorooctanoic acid and perfluorooctane sulfonate at environmentally relevant concentrations via the 'mesh trap' of triazine-based polymer network: Mechanism and photocatalytic regeneration

J Hazard Mater. 2024 Nov 27:483:136698. doi: 10.1016/j.jhazmat.2024.136698. Online ahead of print.

Authors

Boru Gao¹, Lairong Wu², Shaokang Li³, Jinjin Yang³, Mengmeng Dou⁴, Genwang Chang³, Xiang Li⁵

Affiliations

¹ State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Environmental, Beijing Jiaotong University, Beijing 100044, China.
² Zhejiang Huafon Thermoplastic Polyurethane Co., Ltd., Wenzhou, Zhejiang 325000, China.
³ State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
⁴ Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Environmental, Beijing Jiaotong University, Beijing 100044, China. Electronic address: mmdou@bjtu.edu.cn.
⁵ State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China. Electronic address: lixiang@craes.org.cn.

PMID: 39612877
DOI: 10.1016/j.jhazmat.2024.136698

Abstract

Per- and polyfluoroalkyl substances (PFAS) pose a serious threat to groundwater (GW) environment worldwide due to their difficulty in removal and high toxicity. In this study, the 'mesh trap' of triazine-based polymerization network (SNW-1) demonstrated rapid capture performance for Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS) at environmentally relevant concentrations (1 μg/L). The SNW-1 can remove more than 90 % of PFOA and PFOS within 300 s and still maintain superior performance under four common GW anions and different [pH]₀ (3 - 10). The removal degree of PFOA and PFOS is almost undetectable without SNW-1 dosage. Theoretical calculations were used to simulate the adsorption process and interfacial reaction mechanism in SNW-1/PFOA (E_ads = -1.6717 eV) and SNW-1/PFOS (E_ads = -1.2695 eV) systems. The adsorption of SNW-1/PFOA is stronger than SNW-1/PFOS. The typical van der Waals weak interactions between SNW-1 and PFOA were confirmed, which is slightly stronger than SNW-1/PFOS. In addition, SNW-1 regeneration in this paper was achieved in a photocatalytic activated peroxydisulfate (PDS) system which was different with previous reports. The desorption rates of PFOA and PFOS adsorbed on the surface of SNW-1 and the defluorination rate in the photocatalytic regeneration system were also tested. The photocatalytic regeneration mechanism between SNW-1 and PDS was electron transfer. And the electron transfer can be divided into three stages: strong adsorption of SNW-1/PDS (E_ads = -2.1618 eV), electron transfer from SNW-1 to PDS and PDS cleavage. This study has a broad application prospect in the field of in-situ rapid resistance control of GW in PFAS contaminated sites and provides a theoretical support for environmentally friendly adsorbent regeneration technology.

Keywords: Adsorption; Mesh Trap; PFAS; Photocatalytic regeneration; Polymer Network.