Disclosed is a process for the preparation of fluorine-containing olefins comprising contacting a chlorofluoroalkane with hydrogen in the presence of a catalyst at a temperature sufficient to cause replacement of the chlorine substituents of the chlorofluoroalkane with hydrogen to produce a fluorine-containing olefin. Also disclosed are catalyst compositions for the hydrodechlorination of chlorofluoroalkanes comprising copper metal deposited on a support, and comprising palladium deposited on calcium fluoride, poisoned with lead and reducing the in the presence or absence of a dehydrochlorination catalyst under conditions effective to form a product stream comprising cis-1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336).