Conversion of CHF3 to CH2CF2 via reaction with CH4 in the presence of CBrF3: An experimental and kinetic modelling study

Gas-phase reaction of CHF3 (HFC 23) with CH4 in the presence of CBrF3 (halon 1301) to produce CH2CF2 (VDF) is presented. Experiments were carried out in a plug-flow reactor at temperatures between 873 and 1173K. Under these conditions, CH2CF2 was a dominant product observed, with CH2F2, C2H2, CH2CHF, C2F4, C2H6 and CHFCF2 also detected. In the presence of less than 6000ppm of CBrF3, the rate of formation of CH2CF2 is significantly enhanced, and a much lower rate of formation of the major by-product, C2F4 is observed. Further increasing the proportion of CBrF3 in the feed resulted in an even higher rate of formation of CH2CF2. Experimental results are fitted very well by a model derived from the NIST and GRI-Mech 3.0 mechanisms, modified to include additional published kinetic data