Treatment of aniline contaminated water by a self-designed dielectric barrier discharge reactor coupling with micro-bubbles: optimization of the system and effects of water matrix

BACKGROUND A self-designed dielectric barrier discharge reactor coupling with micro-bubbles (DBD/MB) system is proposed as a promising method to remove aniline in waste water. The optimum geometric dimensions of the reactor and the operating parameters of the DBD/MB system as well as the influence of the water matrix (including cations, anions, and coexisting organics) were investigated. The functional mechanisms of the DBD/MB system were explored. RESULTS By setting the double-dielectric barrier discharge reactor (DDBD) with electrode gap as 5 mm, discharge voltage as 50 kV, and air intake flow of the MB generator as 40 mL min(-1), the aniline removal efficiency reached 82% within an hour. The removal efficiency could be promoted by the presence of metal ions (Cu2+, Fe2+ and Mn2+), while it was also found that with the presence of certain anions (CO32-, Cl-, NO3- and SO42-), the degradation process was inhibited by more than 40%. The coexisting organics did not influence aniline removal. Active species (center dot OH, H2O2 and O-3) generated in the DDBD/MB treatment and micro-bubbles played important roles in the aniline degradation process. CONCLUSIONS This study provides fundamental information for the application of a DDBD/MB system to effectively remove aniline from water. (c) 2018 Society of Chemical Industry