Toluene oxidation in a plasma-catalytic system

Abstract

Oxidative removal of toluene in a dielectric barrier discharge reactor combined with manganese catalysts downstream was investigated. Toluene input concentration was varied in the range of $415–2227\mathrm{ppm}$ . The discharge was operated in pulsed mode, with short pulses of $23–35\mathrm{kV}$ peak voltage. At $7\mathrm{W}$ average power, toluene conversion was 60%–70%, independent on the toluene input concentration and on the total gas flow rate in the range of $110–330\mathrm{SCCM}$ (SCCM denotes cubic centimeter per minute at STP). Toluene total oxidation was favored at high residence time of the gas in the discharge zone and low toluene concentration, when the main reaction product was $\mathrm{C}{\mathrm{O}}_2$ with selectivities of 80%–85%. The addition of the catalysts led to a 15%–20% increase in toluene conversion with respect to the values obtained in the plasma, due to oxidation with ozone on the catalyst surface.