Continuous low-temperature process to produce trans-1-chloro-3,3,3-trifluoropropene
View Patent ↗Disclosed is process for the production of (E) 1-chloro-3,3,3-trifluoropropene (HCFO-1233zd(E)) by conducting a continuous reaction without the use of a catalyst. Also disclosed is an integrated system including one or more reactors for producing hydrofluoro olefins, particularly 1233zd(E). The manufacturing process includes six major unit operations: (1) a fluorination reaction of HCC-240fa (in continuous or semi-batch mode) using HF with simultaneous removal of by-product HCl and the product 1233zd(E); (2) recycle of unreacted HCC-240fa and HF together with under-fluorinated by-products back to (1); (3) separation and purification of by-product HCl; (4) separation of excess HF back to (1); (5) purification of final product, 1233zd(E); and (6) isomerization of by-product 1233zd(Z) to 1233zd(E) to maximize the process yield.
1. A method for the production of (E)1-chloro-3,3,3-trifluoropropene without the use of a catalyst comprising the steps of;
(a) operating one or more agitated reaction vessels, each vessel in succession converting a portion of the original reactants fed to the first of the reaction vessels, with all of the reaction vessels being run simultaneously and operating in a continuous fashion;
(b) conducting, in each of the reaction vessels, a series of fluorination reactions of a starting material selected from the group consisting of 1,1,1,3,3-pentachloropropane, 1,1,1,3,3-pentachloropropane, 1,1,3,3-tetrachloropropene, and 1,3,3,3-tetrachloropropene, and any mixtures thereof, using HF with simultaneous removal of by-product HCl and the product (E)1-chloro-3,3,3-trifluoropropene;
(c) recycling at least a portion of any unreacted starting material and HF together with any under-fluorinated by-products back to step (b);
(d) separating and purifying by-product HCl;
(e) separating excess HF back to step (b);
(f) purifying the desired product, (E)1-chloro-3,3,3-trifluoropropene; and
(g) isomerization any by-product (Z)1-chloro-3,3,3-trifluoropropene to (E)1-chloro-3,3,3-trifluoropropene to maximize the process yield.
2. The method of claim 1 , wherein a continuous stream of unconverted starting materials, under-fluorinated intermediates, and some unreacted HF are taken from the bottom of the first reaction vessel and fed to a second reaction vessel.
3. The method of claim 2 , wherein additional HF is added as required.
4. The method of claim 1 , wherein a continuous stream of unconverted starting material, under-fluorinated intermediates, and some unreacted HF is taken from the bottom of the second reaction vessel and fed to a third reaction vessel.
5. The method of claim 4 , wherein additional HF is added as required.
6. The method of claim 1 , wherein the reactor is maintained at a temperature range of 65° C. to 175° C.
7. The method of claim 1 , wherein the reactor is maintained at a temperature range of 85° C. to 170° C.
8. The method of claim 1 , wherein the reactor is maintained at a temperature range of 95° C. to 160° C.