In this study, a wet scrubber coupled with a persulfatebased advanced oxidation process [carbocatalysts/peroxymonosulfate (PMS)] was demonstrated to efficiently remove gaseous volatile organic compounds (VOCs). The removal efficiency of a representative VOC, styrene, was stable at above 98%, and an average mineralization rate was achieved at 76% during 2 h. The removal efficiency of the carbocatalysts/PMS wet scrubber for styrene was much higher than that of pure water, carbocatalysts/water, or PMS/water systems. Quenching experiments, electron spin resonance spectroscopy, in-situ Raman spectroscopy and density functional theory (DFT) calculations indicated that singlet oxygen ( 1 O 2 ) and oxidative complexes are the main reactive oxygen species and that both contributed to styrene removal. In particular, carbonyl groups (C�O) in the carbocatalyst were found to be the active sites for activating PMS during styrene oxidation. The role of 1 O 2 was discovered to be benzene ring breaking and a possible non-radical oxidation pathway of styrene was proposed based on time-of-flight mass spectroscopy which was further verified by DFT calculations. In particular, the electron transfer process of multi world carbon nanotubes-PMS* in styrene oxidation was further studied in-depth by experiments and DFT calculations. The unstable vinyl on styrene was simultaneously degraded by the oxidative complexes and 1 O 2 into benzene, and finally oxidized by 1 O 2 into H 2 O and CO 2 . This study provides an effective method for VOC removal and clearly illustrates the complete degradation mechanism of styrene in a nonradical PMS-based process by a wet scrubber.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.