PLASMA-ASSISTED DECOMPOSITION OF METHANOL AND TRICHLOROETHYLENE IN ATMOSPHERIC-PRESSURE AIR STREAMS BY ELECTRICAL-DISCHARGE PROCESSING

Experiments are presented on the plasma-assisted decomposition of dilu te concentrations of methanol and trichloroethylene in atmospheric pre ssure air streams by electrical discharge processing. This investigati on used two types of discharge reactors, a dielectric-banier and a pul sed corona discharge reactor, to study the effects of gas temperature and electrical energy input on the decomposition chemistry and byprodu ct formation. Our experimental data on both methanol and trichloroethy lene show that, under identical gas conditions, the type of electrical discharge reactor does not affect the energy requirements for decompo sition or byproduct formation. Our experiments on methanol show that d ischarge processing converts methanol to COx with an energy yield that increases with temperature. In contrast to the results from methanol, COx is only a minor product in the decomposition of trichloroethylene . In addition, higher temperatures decrease the energy yield for trich loroethylene. This effect may be due to increased competition from dec omposition of the byproducts dichloroacetyl chloride and phosgene. In all cases plasma processing using an electrical discharge device produ ces CO preferentially over CO2.