Plasma Chemistry and Plasma Processing, Vol.36, No.6, 1501-1515, 2016
Abatement of Gaseous Xylene Using Double Dielectric Barrier Discharge Plasma with In Situ UV Light: Operating Parameters and Byproduct Analysis
Ultraviolet (UV) light with a wavelength of 254 nm was applied to a double dielectric barrier discharge (DDBD) system to decompose of gaseous xylene. The results show that a significantly synergistic effect can be achieved with the introduction of UV light into the DDBD system. When UV light is applied, the system show a 21.8 % increase in its removal efficiency for xylene at 35 kV with an ozone concentration close to 971 ppmv. The CO (x) (x = CO2 and CO) selectivity of outlet gas rises from 6.54 to 76.2 %. The optimal synergetic effect between UV light and DDBD can be obtained at a peak voltage of 30 kV. The system is robust for humidity, which only slightly reduces the xylene removal efficiency at a high peak voltage (30-35 kV). With the increase of gas flow rate, the removal efficiency for xylene decreases due to a reduced residence time. In addition, the products of xylene degradation were also analyzed. The major products of the degradation were found to be CO2 and H2O while byproducts such as O-3 and HCOOH were observed as well.
Keywords:Double dielectric barrier discharges (DDBD);Ultraviolet (UV);Volatile organic compounds (VOCs);Byproducts identification