The invention relates to a process to prepare tetrahalopropenes, such as 2-chloro-3,3,3-trifluoropropene (1233xf). The process comprises atomizing a feed material, such as 1,1,2,3-tetrachloropropene (1230xa) and the like, and mixing it with superheated HF to form a vaporized composition of feed material and HF with substantially instantaneous contact with a vapor phase fluorination catalyst. The invention extends catalyst life and forestalls catalyst deactivation.