ABSTRACT In plasma reactors, the heterogeneous processes occurring on the solid surfaces (electrodes, walls, packing) may influence the reactions of active species (radicals) being produced under plasma conditions. When the solid surface exposes a catalytic activity the heterogeneous reactions may be utilized for the selective generation of a desired product. The catalytic action of solid surfaces was studied under low temperature non-equilibrium plasma conditions at atmospheric pressure. When using the packing of porous silica in the DBD ozonizer, it was found that higher ozone concentrations and energy efficiency may be achieved. In the plasma-catalytic system, with the same kind of discharge, the effects of selected catalysts on the methane and CCl4 conversion were found to be remarkable. The gliding-discharge reactor of a special shape was designed for studying the effect of spouted bed of solid catalyst particles on the methane conversion to C2 hydro-carbons. The increased reaction rate was observed also in the coupled system of a gliding discharge with a stable catalytic bed for the nitrous oxide destruction. Considering the conditions in the plasma-catalytic systems it should be noticed that the homogeneous reactions of radicals and excited molecules in the gas phase may be very fast and thus, the catalyst should be located within the plasma zone in order to make use of its catalytic activity.
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