Percarbonate-periodate system: A novel and efficient “oxidant-oxidant” strategy for selective oxidation of micropollutants in water

The development of effective and selective oxidation technology in complex water matrices is crucial for water ecological security. This study reports for the first time the synergistic use of “oxidant-oxidant” about sodium percarbonate (SPC) and periodate (PI) to selectively degrade organic micropollutants. The SPC/PI system showed degradation rates of 0.0946–0.2978 min −1 for various pollutants, which was 3.7–1787 times higher than those in the PI alone and SPC alone systems and can achieve the effect of H 2 O 2 /PI systems. Additionally, SPC/PI was a safe water treatment technology without generating reactive iodine species (e.g., HOI). The slightly reduced removal rate of bisphenol F under different ionic species and strengths is indicative of the good anti-interference of the SPC/PI system. Scavenging, probe, and electron spin resonance experiments showed that ▪ OH and CO 3 ▪- played a major role in this process, rather than O 2 ▪- and 1 O 2 . Finally, the oxidized products and the possible transformation pathways of three different micropollutants in the SPC/PI and H 2 O 2 /PI systems were characterized and clarified, and the toxicity of the degradation products was predicted. Generally, the study proposed a new selective oxidation strategy of SPC/PI that can effectively eliminate micropollutants in water treatment and clarified the interaction mechanisms between PI and SPC.