High purity HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze) and methods for producing same
The present disclosure provides high purity E-1,3,3,3-tetrafluoropropene (HFO-1234ze). More specifically, the present disclosure provides E-1,3,3,3-tetrafluoropropene (HFO-234ze) in at least 99.99% purity, containing less than 3 ppm 1,1,3,3,3-pentafluoropropene (HFO-1225zc). The present disclosure further provides a method of making high purity E-1,3,3,3-tetrafluoropropene (HFO-1234ze).
1. A method of making HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze), the method comprising:
(a) purifying a stream of 1,1,1,3,3-pentafluoropropane (HFC-245fa);
(b) dehydrofluorinating the purified stream of 1,1,1,3,3-pentafluoropropane (HFC-245fa) to thereby produce a result comprising HFO-Z-1,3,3,3-tetrafluoropropene (cis-HFO-1234ze), HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze), and hydrogen fluoride;
(c) isomerizing at least a portion of the HFO-Z-1,3,3,3-tetrafluoropropene (cis-HFO-1234ze) into HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze);
(d) passing the HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze) through a water scrubber, a caustic scrubber and a sulfuric acid drier;
(e) passing the HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze) through at least one distillation column; and
(f) recovering purified HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze) of at least 99.99% purity and including 5 ppm or less 1,1,3,3,3-pentafluoropropene (HFO-1225zc).
2. The method of claim 1 , wherein step (a) further comprises passing a stream of a stream 1,1,1,3,3-pentafluoropropane (HFC-245fa) through one or more distillation columns to produce a purified stream of 1,1,1,3,3-pentafluoropropane (HFC-245fa).
3. The method of claim 1 , wherein the purified 1,1,1,3,3-pentafluoropropane (HFC-245fa) comprises 1-chloro-1,1,3,3,3-pentafluoropropane (HFC-235fa) in an amount of about 50 ppm or less.
4. The method of claim 1 , wherein the purified 1,1,1,3,3-pentafluoropropane (HFC-245fa) comprises 2-chloro-1,1,3,3,3-pentafluoropropane (HFC-235da) in an amount of about 50 ppm or less.
5. The method of claim 1 , wherein the purified 1,1,1,3,3-pentafluoropropane (HFC-245fa) comprises 1,1,1,3,3,3-hexafluoropropane (HFC-236fa) in an amount of about 50 ppm or less.
6. The method of claim 1 , wherein the purified 1,1,1,3,3-pentafluoropropane (HFC-245fa) comprises 1,1,2,3,3,3-hexafluoropropane (HFC-236ea) in an amount of 50 ppm or less.
7. The method of claim 1 , wherein the purified HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze) is at least 99.999% pure and includes 3 ppm or less 1,1,3,3,3-pentafluoropropene (HFO-1225zc).
8. The method of claim 1 , wherein the purified HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze) is at least 99.9995% pure and includes 3 ppm or less 1,1,3,3,3-pentafluoropropene (HFO-1225zc).
9. A method of making HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze), the method comprising:
(a) purifying a stream of 1,1,1,3,3-pentafluoropropane (HFC-245fa) by passing through one or more distillation columns to produce a purified stream of 1,1,1,3,3-pentafluoropropane (HFC-245fa) having a content of at least one of 1-chloro-1,1,3,3,3-pentafluoropropane (HFC-235fa), 2-chloro-1,1,3,3,3-pentafluoropropane (HFC-235da), 1,1,1,3,3,3-hexafluoropropane (HFC-236fa), and 1,1,2,3,3,3-hexafluoropropane (HFC-236ea) of about 50 ppm or less;
(b) dehydrofluorinating the purified stream of 1,1,1,3,3-pentafluoropropane (HFC-245fa) to thereby produce a result comprising HFO-Z-1,3,3,3-tetrafluoropropene (cis-HFO-1234ze), HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze), and hydrogen fluoride;
(c) isomerizing at least a portion of the HFO-Z-1,3,3,3-tetrafluoropropene (cis-HFO-1234ze) into HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze);
(d) passing the HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze) through at least one distillation column; and
(e) recovering purified HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze) including 5 ppm or less 1,1,3,3,3-pentafluoropropene (HFO-1225zc).
10. The method of claim 9 , wherein the purified 1,1,1,3,3-pentafluoropropane (HFC-245fa) comprises 1-chloro-1,1,3,3,3-pentafluoropropane (HFC-235fa) in an amount of about 50 ppm or less.
11. The method of claim 9 , wherein the purified 1,1,1,3,3-pentafluoropropane (HFC-245fa) comprises 2-chloro-1,1,3,3,3-pentafluoropropane (HFC-235da) in an amount of about 50 ppm or less.
12. The method of claim 9 , wherein the purified 1,1,1,3,3-pentafluoropropane (HFC-245fa) comprises 1,1,1,3,3,3-hexafluoropropane (HFC-236fa) in an amount of about 50 ppm or less.
13. The method of claim 9 , wherein the purified 1,1,1,3,3-pentafluoropropane (HFC-245fa) comprises 1,1,2,3,3,3-hexafluoropropane (HFC-236ea) in an amount of 50 ppm or less.
14. The method of claim 9 , wherein the purified HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze) is at least 99.999% pure and includes 3 ppm or less 1,1,3,3,3-pentafluoropropene (HFO-1225zc).
15. The method of claim 9 , wherein the purified HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze) is at least 99.9995% pure and includes 3 ppm or less 1,1,3,3,3-pentafluoropropene (HFO-1225zc).
16. The method of claim 9 , further comprising the additional step, prior to step (d), of passing the HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze) through at least one of a water scrubber, a caustic scrubber and a sulfuric acid drier.
17. The method of claim 9 , wherein the purified HFO-E-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze) is at least 99.999% pure.