process for isomerizzare 1,1,2 - trifluoro - 1,2-dichloroethane to 1,1,1-trimethylol-p trifluoro - 2,2, - dichloroethane

摘要

1,1,2-trifluoro-1,2-dichloroethane (A123a) is isomerized to 1,1,1-trifluoro-2,2-dichloroethane (A123) by contacting it with AlF7 at temperatures ranging from 180 DEG to 400 DEG C. Advantageously, it is operated with mixtures of A123a with A123 and/or other chlorofluorocarbons coming from the preparation of A123 by hydrofluorination of perchloroethylene.