Heterogeneous Activation of Persulfate by Petal-Shaped Co 3 O 4 @BiOI to Degrade Bisphenol AF.

In catalytic tests, the results have shown that almost all the BPAF was removed within 30 min when the dosage of Co₃O₄@BiOI and sodium persulfate (PS) was 0.15 g and 0.1 mM, respectively. Acid conditions inhibited BPAF degradation, but the inclusion of a precise concentration of bicarbonate ions (HCO₃⁻) promoted degradation. The presence of chloride (Cl⁻), sulfate ions (SO₄²⁻), and a high concentration of HCO₃⁻ inhibited the degradation process, whereas the addition of nitrate ions (NO₃⁻) had a minor effect on the catalytic process. The presence of free radicals (sulfate (SO₄^•−), hydroxyl (•OH), and superoxide (O₂^•−)) and the non-free radical singlet oxygen (¹O₂) in the Co₃O₄@BiOI/PS system was determined by electron paramagnetic resonance (EPR) and quenching tests. We propose that the Co(II)/Co(III) and Bi(III)/Bi(V) redox pairs simultaneously activate PS where the Co₃O₄ and BiOI components work synergistically to promote the rapid oxidative degradation of BPAF in water. [ABSTRACT FROM AUTHOR]