One-step conversion of ethane to ethylene oxide in AC parallel plate dielectric barrier discharge

Abstract

This work studied the one-step conversion of ethane (C2H6) to ethylene oxide (EO) in an AC parallel plate dielectric barrier discharge (DBD) system with two frosted glass plates under ambient temperature and atmospheric pressure. EO is directly produced from C2H6 in a single step without the requirement to separate and recycle ethylene. The effects of the applied voltage, input frequency, and O2/C2H6 feed molar ratio on the EO synthesis performance were examined. The results showed that a higher applied voltage and lower input frequency generated more highly energetic electrons, resulting in a higher current. More electrons collided with reactant gas molecules to initiate plasma reactions, increasing C2H6 and O2 conversions. The increased O2/C2H6 feed molar ratio enhanced C2H6 and O2 conversions. The optimum conditions were found to be an applied voltage of 7 kV, input frequency of 550 Hz, and O2/C2H6 feed molar ratio of 1:1, which demonstrated the highest EO selectivity (42.6%), EO yield (19.4%), and lowest power consumption per EO molecule produced (6.7 x 10-18 Ws/molecule).

Keywords

• dielectric barrier discharge
• epoxidation
• ethane oxidative dehydrogenation
• ethylene oxide
• one-step reaction