The Coupling Use of Weak Magnetic Field and Fe0/H2O2 Process for Bisphenol a Abatement: Influence of Reaction Conditions and Mechanisms

The coupling use of the heterogeneous Fenton-like process (zero-valent iron (Fe-0)/H2O2) and weak magnetic field (MWF) for bisphenol A (BPA) abatement was systematically investigated in this study. Though both the Fe-0/H2O2 and WMF-Fe-0/H2O2 processes are sensitive to pH, WMF remarkably enhanced BPA removal under the pH range of 3.0-6.0 by 0.5-9.5 times. The characterization of Fe-0 confirmed the role of WMF in promoting the corrosion of Fe-0. Radicals, rather than Fe intermediates, were responsible for BPA degradation. Due to the presence of Cl- as the background ions and its reactivity towards HO center dot, reactive chlorine species (RCS, i.e., Cl-center dot and Cl-2(center dot)) were produced and considerably contributed to BPA degradation. In addition, similar to 37% and 54% of degraded BPA was ascribed to RCS in the presence of 2 and 100 mM of Cl, respectively. However, 1.9 mg/L of ClO3- was detected in the presence of 2 mM of Cl- in the WMF-Fe-0/H2O2 process. HCO3- could diminish ClO3- generation significantly through transforming RCS. The concentration of ClO3- decreased by 74% and 82% with dosing 1 and 10 mM HCO3-, respectively. The results of this study suggest that the WMF-Fe-0/H2O2 process is a promising approach for BPA removal.

Automated summary

The study systematically investigated the coupling use of the heterogeneous Fenton-like process (zero-valent iron (Fe-0)/H2O2) and weak magnetic field (MWF) for bisphenol A (BPA) abatement. The results showed that the presence of Cl- as background ions significantly contributed to the generation of reactive chlorine species (RCS) and ClO3- in the process, while HCO3- played a role in diminishing the generation of ClO3-.