Energy efficient treatment of indoor volatile organic compounds using a serial dielectric barrier discharge reactor

Abstract Volatile organic compounds (VOCs) generated in urban workplaces have been considered as significant air pollutants both indoors and outdoors. In order to reduce those harmful VOCs from urban emission sources, a non-thermal plasma reactor equipped with dielectric barrier discharge (DBD) using alternating current (AC) was investigated with a focus on process design including recirculation. Decomposition efficiency of low concentration VOCs was evaluated in terms of energy yield and conversion selectivity. At 20 ppm, the highest decomposition efficiency (97.3 %) was achieved in the treatment of n-hexane, followed by toluene at 96.6 %, MEK at 91.5 % and acetaldehyde at 90.4 %. A recirculation rate (QR) of 50 % improved the system efficiency, particularly for acetaldehyde (49.47 %–63.86 %) and toluene (79.05 %–95.89 %). It also increased the complete energy yield and the selectivity for carbon monoxide (CO) and carbon dioxide (CO2). By-product ozone concentration decreased significantly with increasing recirculation rate at the same input energy level.