In this work, ethylene epoxidation reaction for ethylene oxide production over silver catalysts loaded on two different supports (silica and alumina particles) in a lowtemperature AC dielectric barrier discharge (DBD) reactor was investigated. The DBD plasma system was operated under the following base conditions: an O 2 /C 2 H 4 feed molar ratio of 1/4, a total feed flow rate of 50 cm 3 /min, an electrode gap distance of 0.7 cm, an input frequency of 500 Hz, and an applied voltage of 19 kV. From the results, the presence of silver catalysts improved the ethylene oxide production performance. The silica support interestingly provided a higher ethylene oxide selectivity than the alumina support. The optimum Ag loading on the silica support was found to be 20 wt%, exhibiting the highest ethylene oxide selectivity of 30.6%.

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This work investigated ethylene epoxidation performance using a parallel plate dielectric barrier discharge (DBD) system with a separate ethylene/oxygen feed in order to produce oxygen active species prior to reaction with ethylene. The highest ethylene oxide (EO) selectivity of 73% was obtained when the combined catalytic−DBD system was operated at an ethylene feed position of 0.5, an O 2 /C 2 H 4 feed molar ratio of 0.2:1, and an Ag loading of 10 wt %. The presence of a glass platesupported Ag catalyst provided considerably higher EO selectivity, twice as much as that of the DBD system alone. As compared to the DBD system with an Ag catalyst supported on glass beads, the glass plate dielectric barrier was found to be a more efficient support for ethylene epoxidation. This is because the glass plate system provided plasma that was more uniform than that provided by the glass bead system.