Process to manufacture 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb)
The invention provides an improved process to manufacture 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) by reacting 2-chloro-3,3,3,-trifluoropropene (HCFO-1233x1) with hydrogen fluoride, in a liquid phase reaction in the presence of hydrogen chloride and a liquid phase fluorination catalyst. The hydrogen chloride is added into the reaction from an external source at a pressure of about 100 psig or more. The HCFC-244bb is an intermediate in the production of 2,3,3,3-tetrafluoropropene-1 (HFO-1234yf).
1. A process for the production of 2-chloro-1,1,1,2-tetrafluoropropane which comprises reacting 2-chloro-3,3,3,-trifluoropropene with hydrogen fluoride, in a liquid phase reaction in the presence of hydrogen chloride and a liquid phase fluorination catalyst, wherein the hydrogen chloride is added into the reaction from an external source at a pressure of about 100 psig or more.
2. The process of claim 1 wherein the reacting is conducted in a liquid phase reaction vessel.
3. The process of claim 1 wherein the reacting is conducted continuously.
4. The process of claim 1 wherein the mole ratio of hydrogen fluoride to 2-chloro-3,3,3-trifluoropropene fed to the reaction ranges from at least 1:1 to about 50:1.
5. The process of claim 1 wherein the mole ratio of hydrogen chloride to 2-chloro-3,3,3-trifluoropropene fed to the reaction ranges from at least 0.1:1 to about 10:1.
6. The process of claim 1 wherein the liquid phase fluorination catalyst comprises SbCl 5 , SbCl 3 , SbF 5 , SnCl 4 , TaCl 5 , TiCl 4 , NbCl 5 , MoCl 6 , FeCl 3 , CrF 3 , Cr 2 O 3 , a fluorinated species of SbCl 5 , a fluorinated species of SbCl 3 , a fluorinated species of SnCl 4 , a fluorinated species of TaCl 5 , a fluorinated species of TiCl 4 , a fluorinated species of NbCl 5 , a fluorinated species of MoCl 6 , a fluorinated species of FeCl 3 , a fluorinated species of Cr 2 O 3 , or combinations thereof.
7. The process of claim 1 wherein the reacting is conducted at a temperature of from about 30° C. to about 200° C.
8. The process of claim 1 wherein the reacting is conducted at a pressure of from about 5 psia to about 200 psia.
9. The process of claim 1 further comprising the step of recovering the hydrogen chloride.
10. The process of claim 1 , further comprising fluorinating 1,1,2,3,-tetrachloropropene to produce the 2-chloro-3,3,3,-trifluoropropene.
11. The process of claim 10 wherein the 1,1,2,3,-tetrachloropropene is fluorinated with hydrogen fluoride and the reacting thereby produces an intermediate stream comprising hydrogen fluoride, 2-chloro-3,3,3,-trifluoropropene and hydrogen chloride.
12. The process of claim 11 further comprising the step of recovering the hydrogen chloride.
13. The process of claim 12 wherein at least a part of the recovered HCl stream is directly fed to the liquid phase reactor.