Decomposition of volatile organic compounds by a novel electrode system integrating ceramic filter and SPCP method

We developed a new efficient apparatus for gas treatment in which a ceramic filter and SPCP (surface corona discharge induced plasma chemical process) were integrated. In this study, the feasibility of the reactor to decompose volatile organic compounds (VOCs) and performance were evaluated. The efficiency was examined against various conditions of initial concentration of VOCs, as trichloroethylene (TCE), toluene and benzene, and by using variable flow rates of carrier gases (air, nitrogen, and mixture of nitrogen and oxygen or water vapor). TCE was decomposed effectively within the reactor system, especially when the carrier gas contains oxygen or water as an oxygen source, whilst the decomposition efficiency was low with the nitrogen carrier. With a sufficient oxygen source, no organic by-products were detected in the treated gas, and TCE was oxidized to inorganic substances. Toluene and benzene were efficiently decomposed as well. For performance evaluation of such non-thermal plasma reactors for VOC treatment, we proposed a new parameter which is derived with substance based energy density, mSED (J/mol). The new parameter has merit to express the performance with a single parameter for a range of discharge power, flow rates, and initial concentrations of the gas to be treated. With the parameter proposed, the evaluation resulted in a new reactor in this study that has as high a performance as a conventional packed-bed reactor, and their performances are higher than pulse corona (PC), and dielectric barrier discharge reactors. (C) 2006 Elsevier B.V. All rights reserved.