Disclosed is a process for the manufacture of 1234yf from 1,1,2,3-tetrachloropropene, abbreviated herein as “TCP,” in three integrated steps: (a) the R-1 hydrofluorination of TCP to form 1233xf in the vapor phase; (b) the R-2 hydrofluorination of 1233xf to form 244bb in either the liquid phase or in the liquid phase followed by the vapor phase; and (c) the R-3 dehydrochlorination of the 244bb in either the liquid or the vapor phase to produce 1234yf; wherein the vapor phase hydrofluorination of TCP in step (a) is carried out at a higher pressure than the liquid phase hydrofluorination of 1233xf; andwherein the HC1 generated during these steps is scrubbed with water to form an acid solution and the organic components are scrubbed with a caustic solution and then dried before further processing.