Enhanced degradation of butyl xanthate by hydrogen peroxide and persulfate using micro-nano bubble

Xanthates are the main trapping agents used in the processing of metallic sulfide ores and residual xanthates in beneficiation wastewater can potentially contaminate the environment at the mine site. Finding efficient methods to degrade butyl xanthates has received much attention. Micro-nano bubble (MNB) and advanced oxidation technologies (AOPs) have recently become increasingly important as effective treatment methods. In this study, the degradation of butyl xanthate was investigated through a micro-nano bubble-enhanced Fenton process (hydrogen peroxide (H2O2)/ peroxymonosulfate (PMS) /Fe2+). The effects of the process parameters (pH, coexisting ions, oxidant dosage (PMS, H2O2), and Fe-2(+) dosage) on the degradation of butyl xanthate were investigated. Results showed that the H2O2/PMS/Fe2+ process resulted in a 100 % degradation rate for butyl xanthate and 66 % total organic carbon (TOC) removal rate. With the enhancement of the degradation process using MNBs, the TOC removal rate increased to 80 %. The hydroxyl and superoxide radicals were identified as the main active substances in the degradation of butyl xanthate through electron spin resonance. Introducing H2O2 into the PMS/Fe2+ process increased the strength of hydroxyl and superoxide radicals in the reaction system. In addition, following the introduction of the MNBs, the amount of dissolved oxygen in the reaction system increased. As a result, the production of active substances in the reaction system increased. The synergistic effect of MNBs and the Fenton process caused an increase in the TOC removal rate. This implies that the multiprocess coupling technology of the MNB-enhanced Fenton process has great potential in the field of wastewater treatment.