Feasibility of Using Sequential Sulfurized Nanoscale Zerovalent Iron-Persulfate Process to Degrade Tetrabromobisphenol A

Tuan Nguyen Quoc,Khanh Hoang Nguyen,Chau Tran Thi Minh,Van-Duong Dao,Thao Thanh Le,Nguyen Thi Hanh Tien,Huong Ngo Thi Thuy,P Davide Cozzoli

doi:10.1155/2021/8053120

Abstract

This study proposed a sequential redox process to partially degrade tetrabromobisphenol A (TBBPA) within a reactor to a great extent. After 72 hours in an anoxic environment, 20 ppm of TBBPA could be effectively degraded by sulfurized zerovalent iron nanoparticles (S-nZVI) at concentrations of 2 g L-1 and 4 g L-1. Biphenol A (BPA) together with tri-, di-, and monobromobisphenol A was detected by high-performance liquid chromatography (HPLC) suggesting that TBBPA was debrominated by S-nZVI in a stepwise manner. Following the S-nZVI treatment, a persulfate-advanced oxidation process (PS-AOP) system with persulfate concentrations varied from 5 to 20 mM was incorporated to degrade the final debrominated byproduct, BPA, for 2 hours. The two-stage anoxic/oxic reactions at the same reactor with initial conditions (0.037 mM TBBPA, 4 g L-1 of S-nZVI, pH 6 in anoxic stage, 20 mM of PS in the latter oxic stage) were investigated. The sulfurized layer played an important role in such a system and hypothetically contributes to increasing electron transfer from Fe0 core as well as hydrophobicity of the NP surface. It was demonstrated that the S-nZVI/PS-AOP system could effectively remediate TBBPA and BPA and consequently provide a promising strategy to remedy brominated organic pollutants in the environment.

Highlights

Tetrabromobisphenol A (TBBPA) is one of the most widely used brominated flame retardants which is designed to improve the fire safety of plastic paints, synthetic textiles, electrical devices, or other materials [1,2,3]
Our study demonstrated that TBBPA and BPA were effectively degraded via the twostage anoxic and oxic processes using S-nanoscale zerovalent iron (nZVI)/PS at nonacidic conditions with the enhancement of dissolved oxygen from the air
A sequential redox process using S-nZVI NPs coupled with PS has been developed and evaluated for the degradation of TBBPA

Summary

Introduction

Tetrabromobisphenol A (TBBPA) is one of the most widely used brominated flame retardants which is designed to improve the fire safety of plastic paints, synthetic textiles, electrical devices, or other materials [1,2,3]. TBBPA is ubiquitous and can be found in many environmental compartments such as the hydrosphere, soil, sewage sludge, sediments, and house dust [3, 4]. It could occur in the biosolids or discharge of wastewater treatment plans if such plans could not treat TBBPA efficiently [5, 6]. TBBPA might potentially occur in agricultural farming if contaminated biosolids or discharge was used [6] This could be one of the entry points for TBBPA to enter the food chain and reach consumers due to its bioaccumulative property. TBBPA is known as a potential endocrine disruptor and a source of oxidative stress in a wide variety of organisms [9] due to its weak estrogen-like properties and being a precursor to bisphenol A (BPA) [3, 10]

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