Degradation of Anthraquinone Dye Wastewater by Sodium Percarbonate with CoO Heterogeneous Activation

Abstract

Abstract In this work, the optimal efficiency and mechanism of action of CoO activated sodium percarbonate (SPC) for the degradation of Reactive Blue 19 was investigated. The three-factor interaction of SPC concentration, CoO dosage and initial pH and the effects of factors such as anions and humic acids (HA) were investigated. The results show that the CoO/SPC system (93.8%, 0.01015 min− 1) efficiently degraded RB19 and was also suitable for other organic dyes (32.7%~100%) and antibiotics (97.1%~100%). During the activation of SPC by CoO, carbonate radical (CO3•−), hydroxyl radical (•OH), superoxide radical (O2•−) and singlet oxygen (1O2) are involved in the degradation process, among which CO3•− (88.2%) plays an indispensable role, which was proved by quenching experiments and electron paramagnetic resonance (EPR) tests. Co2+ dissolution was lower than 150 µg/L, which meets the emission standard (1 ppm); the application of SPC avoids the problem of acidification of the wastewater, and the final product is green in color. This study presents a novel approach to treating dye wastewater by combining transition metal oxides with sodium percarbonate.