Atmospheric-pressure pulsed discharge plasma in capillary slug flow system for dye decomposition

Abstract In this study, the introduction of non-equilibrium atmospheric-pressure plasma in a slug flow reactor system is demonstrated as a chemical reaction medium. The water containing Coomassie Brilliant Blue R − 250 (CBB) and various gas species are used as the liquid and gas phases, respectively, which are flown at 1.5 and 0.5 mL/min. The optical emission spectra indicate that different reactive oxidation species are generated by each gas when the pulsed discharge plasma is applied to the slug flow reactor system. The oxygen-base reactive species are found in abundance. The decoloration of CBB seems to occur, which is indicated by a change in the color of the aqueous solution. The UV − vis spectra show that the order of the CBB decomposition rate is oxygen > air > nitrogen > argon > helium.