Decomposition of ethylene oxide in the rf plasma environment

A radio frequency (RF) plasma system was used to decompose the ethylene oxi de (EO) contained gas in the EO/Ar, and EO/O-2/Ar system, respectively. The reactants and final products were analyzed by using FTIR (Fourier transfor m infrared spectroscopy). The effects of plasma operational parameters, inc luding input power wattage (W), total gas flow rate (Q), feeding concentrat ion (C) of EO and operational pressure for EO decomposition were evaluated. Due to the importance of the high-energy electrons in the RF plasma system , the EO decomposition fraction in plasma reaction increased with decreasin g operational pressure, while that of thermal reaction, reported by previou s investigations, increased with increasing operational pressure. However, owing to the electrophiIic characteristic of oxygen atoms in the EO molecul e causing the effect of electron attachment, in conditions of higher EO fee ding concentration, the pressure dependence became the same for both plasma - and thermal- reaction. The EO oxidation reaction has also been investigat ed, the result shows that EO almost completely oxidized at 600-692 K gas te mperature. The main products for the EO/Ar system are CO, CH4, C2H6, C2H4, and C2H2, and those for the EO/O-2/Ar system are CO2 and H2O.