Reaction between carbon dioxide and elementary fluorine

Reactions between carbon dioxide and fluorine were examined at temperatures of 303–523 K under various pressure and mixture ratios of both gases. Reactions were carried out similarly under the existence of NaF, CsF and EuF3.After the reaction, fluorine was removed and the reaction products were analyzed using FT-IR, GC/FT-IR and GC/MS. The major products were CF3OF, COF2, CF4 and CF2(OF)2.The best yield of COF2 was 11.1% under the reaction condition of CO2/F2 = 76 kPa/76 kPa with temperature of 498 K for 72 h in a direct reaction. The formation rate of COF2 in the direct reaction was estimated as 0.232 dm3 mol−1 h−1 under the reaction conditions of CO2/F2 = 76 kPa/76 kPa, at 498 K. In the presence of CsF, it was estimated as 1.88 dm3 mol−1 h−1 at CO2/F2 = 76 kPa/76 kPa at 498 K.The activation energy of the COF2 formation in the direct reaction was estimated as 45.7 kJ mol−1 at CO2/F2 = 76 kPa/76 kPa at 498 K. In addition, 24.2 and 38.9 kJ mol−1 were evaluated at CO2/F2 = 76 kPa/76 kPa at 498 K, respectively, in the presence of CsF and EuF3.

Scheme of the reaction processes between F2 and CO2. Figure optionsDownload as PowerPoint slide