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β-FeOOH-coupled activated carbon (FAC) was prepared and used to remove bromate from an aqueous phase. SEM, XRD, and FTIR analyses indicated that a larger number of β-FeOOH particles were anchored on the AC surface, which greatly enhanced the bromate adsorption and reduction rates. The influences of the pH, contact time, temperature, and competitive anions on bromate removal by FAC were evaluated. FAC can be used over a wide pH range (3−8) for bromate adsorption and reduction, and competing anions inhibit bromate uptake. The adsorption kinetics agreed well with the pseudo-second-order model (R 2 ≥ 0.99), and the adsorption isotherms were well fitted by the Langmuir model. The thermodynamic analysis suggested that bromate removal by FAC was a spontaneous and endothermic process. Bromate was adsorbed and then reduced to bromide; Fe 3+ acted as a catalyst to accelerate the reductive reaction. The results of this study indicate that FAC is a stable and promising material for bromate removal.

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In this study, the FPA90-Cl resin was magnetized with supported FeO particles using a chemical co-precipitation method and its removal performance of bromate and coexisting precursors was explored. The magnetized FPA90-Cl resin was structurally characterized by SEM, FT-IR, and XRD. The effects of the initial concentrations, temperature, and resin dosage on bromate and bromide ion removal in drinking water were investigated using batch experiments. The magnetized FPA90-Cl resin exhibited a high removal efficiency for bromate and bromide ions at three initial concentrations, and the residual bromate concentrations were under the maximum contaminant level (MCL) of 10 μg L after 80 min. The adsorption data of bromate and bromide ion could be well described by a pseudo-first-order kinetic model (R ˃ 0.98). The bromate removal alone was further studied by varying the initial solution pH, temperature, and competitive anions. The results showed that the magnetized FPA90-Cl resin could be used over a wide pH range (4.0-9.0). The maximum sorption capacity of the magnetized FPA90-Cl resin for bromate reached 132.83 mg g at 298 K. The Freundlich and Redlich-Peterson isotherm models fit the bromate adsorption equilibrium better (R ˃ 0.99) than the Langmuir isotherm model (R ˃ 0.98). The thermodynamic analysis showed that the bromate adsorption process was endothermic. The negative ΔG and positive ΔS indicated that the process was spontaneous and that randomness increased after adsorption, respectively. The competition of coexisting anions with bromate was in the order of SO > CO > Cl > NO > HCO > PO. Additionally, the magnetized FPA90-Cl resin could maintain a high bromate and bromide ion adsorption capacity after five cycles of regeneration by a 0.1 M NaCl solution. Graphical abstract ᅟ.