RADIOTRACERS IN FLUORINE CHEMISTRY. PART IX FLUORINATION OF CHLOROFLUOROETHANES BY CHROMIA CATALYSTS TREATED WITH HYDROGEN FLUORIDE OR HYDROGEN -FLUORIDE

Article abstract of DOI:10.1016/S0022-1139(00)84990-8

Passage of dichlorotetrafluoroethane isomers or 1,1,2-trichloro-1,2,2-trifluoroethane at temperatures >/= 623 K over chromia catalysts, previously treated with hydrogen fluoride at 623 K, leads to the formation of fluorinated and chlorinated products.Incorporation of fluorine-18 radioactivity in the products is observed when hydrogen <(18)F>-fluoride is used in the catalyst pretreatment, indicating the involvement of a surface fluorinecontaining species.The reactions observed are described in terms of series of F-for-Cl and Cl-for-F halogen exchange reactions occurring at the catalyst surface.