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.