Dielectric barrier discharge coupled with Fe2+, Mn2+ and Cu2+ scrubbing for toluene removal

By-product ozone emission is one of the challenges for applying dielectric barrier discharge (DBD) technology for volatile organic compounds (VOCs) removal. In this study, a DBD reactor followed by a wet scrubber (WS) containing a solution of metal ions (Fe2+/Mn2+/Cu2+) was used to reuse ozone for further oxidation of typical VOC toluene. Compared with the degradation effect of the DBD reactor alone, DBD coupled WS/iron system not only improved the toluene removal efficiency but also significantly reduced the ozone emission. The ozone removal efficiency reached as high as 98% in the DBD coupled WS/Fe2+ system. Electron paramagnetic resonance (EPR) tests showed that ozone was converted into radicals such as hydroxyl radicals in Fe2+ and Cu2+ solution, which further oxidized toluene in WS/iron. Quenching experiments showed that the contribution for toluene degradation by radicals was up to 75% and 62% in Fe2+ and Mn2+ reactor, respectively. This study demonstrates that the DBD coupled WS system has the potential to be an environmentally friendly technology for gaseous VOCs removal.

Automated summary

In this study, a DBD reactor coupled with a wet scrubber containing metal ions was used for further oxidation of toluene. The results showed that this system not only improved the removal efficiency of toluene, but also significantly reduced ozone emission. The study demonstrated the potential of the DBD coupled WS system as an environmentally friendly technology for gaseous VOCs removal.