E. Kemnitz, K.-U. Niedersen
Sep 1, 1995
Citations
0
Influential Citations
20
Citations
Journal
Journal of Catalysis
Abstract
Abstract Kinetic and mechanistic studies of the isomerization reactions of 1,1,2,2-tetrafluoroethane to 1,1,1,2-tetrafluoroethane on conditioned chromia were carried out. In contact with the surface of the solid 1,1,2,2-tetrafluoroethane undergoes a separation of HF, forming noticeable amounts of the olefin trifluoroethylene. Due to rearrangement of the adsorbed gas molecules in the surface, HF is re-added, forming 1,1,1,2-tetrafluoroethane according to the Markovnikov rule. CHF 2 CHF 2 ⇄ CHF CF 2 + HF CHF CF 2 + HF ⇄ CH 2 F CF 3 A mathematical adjustment was carried out in order to describe the reaction mechanism. Modelling of the isomerization reaction suggests that the best agreement between the experimental and the calculated data can be achieved when the decomposition of CHF 2 -CHF 2 to HF and CHF CF 2 is considered to be reversible. The experimentally determined values of rate constants indicate a significant influence of the adsorption equilibria on these reactions.