Volatile Organic Compounds (VOCs) Removal by Using Dielectric Barrier Discharge

An experimental study on volatile organic compounds (VOCs) removal with non-thermal plasma generated by dielectric barrier discharge (DBD) in a coaxial cylindrical reactor was carried out at atmospheric pressure and room temperature. During plasma processing to decompose toluene, electrical parameters such as discharge power, equivalent capacitance of the gap (Cg) and the dielectric barrier (Cd), were analyzed using the Q -V Lissajous diagram. In order to optimize the geometry of the DBD reactor, the removal efficiency of toluene was compared for various inner electrode diameters (1.20 mm, 1.65 mm, 2.0 mm) and different reactor materials (ceramic and PMMA). It suggested that, the specific input energy (SIE) depended linearly on the voltage in all cases, and Cg decreased with increasing voltage and gap length. However, with the voltage increasing, Cd increased initially and stabilized at about 700 pF. With respect to toluene conversion, 2.0 mm electrode appeared to be superior to 1.20 mm and 1.65 mm electrodes. In contrast to PMMA reactor, abatement of toluene was enhanced by ceramic reactor possessing high permittivity, especially in the high input energy condition, 73% for ceramic and 62% for PMMA at 660J/1. The energy efficiency for toluene removal stabilized at 5 g/kWh approximately with removal ratio exceeding 50%.