Method for co-producing various alkenyl halides and hydrofluoroalkanes

Abstract

Disclosed is a method for co-producing various alkenyl halides and hydrofluoroalkanes: cis-1-chloro-3,3,3-trifluoropropene is introduced into a first reactor to carry out an isomerization reaction in the presence of a first catalyst, and the reaction product is rectified to obtain a product trans-1-chloro-3,3,3-trifluoropropene; and 30-70 wt % of trans-1-chloro-3,3,3-trifluoropropene and hydrogen fluoride are mixed and then introduced into a second reactor to carry out a reaction in the presence of a second catalyst to obtain a second reactor reaction product; the second reactor reaction product is introduced into a phase separator for separation, and the obtained organic phase is rectified to obtain the products trans-1,3,3,3-tetrafluoropropene, cis-1,3,3,3-tetrafluoropropene and 1,1,1,3,3-pentafluoropropane. The invention has the advantages of simple process, high efficiency, high operation flexibility, less investment and low energy consumption.

Claims

1. A method for co-producing alkenyl halides and hydrofluoroalkanes, comprising following steps of: (a) introducing cis-1-chloro-3,3,3-trifluoropropene into a first reactor where an isomerization reaction occurs in the presence of a first catalyst to obtain a first reactor reaction product, wherein a temperature of the isomerization reaction is 200-400 C., and an air velocity of the isomerization reaction is 300-1000 h.sup.1; (b) introducing the first reactor reaction product obtained in the Step (a) into a first rectification column to obtain a product of trans-1-chloro-3,3,3-trifluoropropene and a first rectification column bottom liquid; (c) mixing 30-70 wt % of the trans-1-chloro-3,3,3-trifluoropropene obtained in the Step (b) with hydrogen fluoride, and then introducing the trans-1-chloro-3,3,3-trifluoropropene and the hydrogen fluoride in a second reactor where a reaction occurs in the presence of a catalyst to obtain a second reactor reaction product, wherein a molar ratio of the hydrogen fluoride to the trans-1-chloro-3,3,3-trifluoropropene is 8-20:1, a temperature of the reaction is 180-400 C., and a space velocity of the reaction is 300-1000 h.sup.1; (d) introducing the second reactor reaction product obtained in the Step (c) into a phase separator for separation to obtain an inorganic phase and an organic phase; (e) introducing the organic phase obtained in the Step (d) into a second rectification column to obtain a product of trans-1,3,3,3-tetrafluoropropene and a second rectification column bottom liquid; (f) introducing the second rectification column bottom liquid obtained in the Step (e) into a third rectification column to obtain a product of cis-1,3,3,3-tetrafluoropropene and a third rectification column bottom liquid; and (g) introducing the third rectification column bottom liquid obtained in the Step (f) into a fourth rectification column to obtain a product of 1,1,1,3,3-pentafluoropropane and a fourth rectification column bottom liquid.

2. The method for co-producing alkenyl halides and hydrofluoroalkanes according to claim 1, wherein the first rectification column bottom liquid in the Step (b) is recycled back to the first reactor.

3. The method for co-producing alkenyl halides and hydrofluoroalkanes according to claim 1, wherein the inorganic phase in the Step (d) is recycled back to the second reactor.

4. The method for co-producing alkenyl halides and hydrofluoroalkanes according to claim 1, wherein the fourth rectification column bottom liquid in the Step (g) is recycled back to the second reactor.

5. The method for co-producing alkenyl halides and hydrofluoroalkanes according to claim 1, wherein in the Step (a) the temperature of the isomerization reaction is 250-320 C., and the air velocity of the isomerization reaction is 500-800 h.sup.1.

6. The method for co-producing alkenyl halides and hydrofluoroalkanes according to claim 1, wherein in the Step (c) the molar ratio of the hydrogen fluoride to the trans-1-chloro-3,3,3-trifluoropropene is 10-15:1, the temperature of the reaction is 200-350 C., and the space velocity of the reaction is 500-700 h.sup.1.

7. The method for co-producing alkenyl halides and hydrofluoroalkanes according to claim 1, wherein the first catalyst in the Step (a) is alumina-loaded chromium and magnesium, wherein the load of chromium is 3-8 wt %, and the load of magnesium is 1-3 wt %.

8. The method for co-producing alkenyl halides and hydrofluoroalkanes according to claim 1, wherein a composition of the second catalyst in the Step (c) comprises, by mass percentage, 73-90% of chrome oxide, 9.5-25% of zinc oxide, and 0.5-2% of gallium oxide.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 is a process flow diagram of the invention.

(2) As shown in the FIGURE: 1 refers to first reactor, 2 refers to first rectification column, 3 refers to second reactor, 4 refers to phase separator, 5 refers to second rectification column, 6 refers to third rectification column, 7 refers to fourth rectification column, 8 to 22 represents process pipelines.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(3) The process of the invention is shown in FIG. 1. The raw material cis-1-chloro-3,3,3-trifluoropropene (HFO-1233zd(Z)) enters a first reactor 1 through a pipeline 8 for reaction to obtain a mixture containing HFO-1233zd(E) and unreacted HFO-1233zd(Z); the mixture is introduced into a pipeline 9 to enter a first rectification column 2; a product HFO-1233zd(E) is taken from the overhead of the first rectification column 2 through a pipeline 10, and unreacted HFO-1233zd(Z) at the bottom of the first rectification column 2 is returned to the first reactor 1 through a pipeline 11; 30 to 70 wt % of HFO-1233zd(E) enters a second reactor 3 through a pipeline 12, and HF enters the second reactor through a pipeline 13 for reaction to obtain a mixture containing HFO-1234ze(E), HFO-1234ze(Z), HFC-245fa, unreacted HFO-1233zd(E), HCL and HF, and the mixture enters a phase separator 4 through a pipeline 14; an inorganic phase containing a large amount of HF and a small amount of organics at the upper layer of the phase separator 4 is returned to the second reactor 3 through a pipeline 15, and an organic phase containing a large amount of organics and a small amount of HF at the bottom layer of the phase separator 4 enters a second rectification column 5 through a pipeline 16, an overhead component of the second rectification column 5 is the product HFO-1234ze(E) and taken out through a pipeline 17, and a mixture containing HFO-1234ze(Z), HFC-245fa and unreacted HFO-1233zd(E) at the bottom of the second rectification column 5 enters a third rectification column 6 through a pipeline 18; an overhead component of the third rectification column 6 is the product HFO-1234ze(Z) and taken out through a pipeline 19, and a mixture containing HFC-245fa and unreacted HFO-1233zd(E) at the bottom of the third rectification column 6 enters a fourth rectification column 7 through a pipeline 20; an overhead component of the fourth rectification column 7 is product HFC-245fa and taken out through a pipeline 21, and unreacted HFO-1233zd(E) at the bottom of the fourth rectification column 7 is returned to the second reactor 3 through a pipeline 22.

(4) The invention is further described in detail below with reference to embodiments, but the invention is not limited to the following embodiments.

Embodiment 1

(5) 200 ml of an Al.sub.2O.sub.3/Cr/Mg catalyst (by mass percentage, composition: 95% of Al.sub.2O.sub.3; 4% of Cr.sub.2O.sub.3; 1% of MgO) is loaded into a first reactor, and the temperature is raised to a bed temperature of 330 C., and HF is introduced for activation at a HF flow rate of 100 g/h and at a hot spot temperature of less than 380 C.; when the hot spot temperature and the bed temperature are the same but no longer raised, the fluorination ends.

(6) The first reactor is heated to the reaction temperature, and HFO-1233zd(Z) is introduced to carry out a reaction, the space velocity of the reactor is maintained at a set value, and after 1 hour of reaction, samples are taken from the outlet of the first reactor for analysis. The reaction results at different temperatures and space velocities are shown in Table 1-1.

(7) TABLE-US-00002 TABLE 1-1 Outlet Organic Composition of the First Reactor in Embodiment 1 Reaction conditions Outlet composition of reactor (%) Temperature Space velocity HFO-1233zd HFO-1233zd ( C.) (h.sup.1) (Z) (E) Other 200 500 63.5 36.4 0.1 250 300 53.4 46.5 0.1 320 800 44.6 55.2 0.2 400 1000 32.7 67 0.3 260 500 49.1 50.8 0.1

(8) 200 ml of a Cr.sub.2O.sub.3/ZnO/GaO catalyst (by mass percentage, composing 80% of Cr.sub.2O.sub.3, 19% of ZnO and 1% of GaO) is loaded into a second reactor, and the temperature is raised to a bed temperature of 350 C., and HF is introduced for activation at a HF flow rate of 100 g/h and at a hot spot temperature of less than 370 C.; when the hot spot temperature and the bed temperature are the same but no longer raised, the fluorination is further carried out for 20 h and then ends.

(9) After separating the outlet mixture of the first reactor, a product HFO-1233zd(E) with the purity of 99.9% is obtained, and 30 wt % of the product HFO-1233zd(E) is introduced into the second reactor together with HF to carry out reaction; and after 1 hour of reaction, samples are taken from the outlet of the second reactor for analysis. The results of the reaction under the conditions of different temperatures, space velocities, and molar ratios of HF to trans-1-chloro-3,3,3-trifluoropropene are shown in Table 1-2.

(10) TABLE-US-00003 TABLE 1-2 Outlet Organic Composition of the Second Reactor in Embodiment 1 Space Temperature velocity HF/HFO-1233zd HFO-1233zd HFO-1234ze ( C.) (h.sup.1) (E) (E) (E) HFO-1234ze (Z) HFC-245fa Other 180 500 10 54.7 1.5 0.5 43.2 0.1 200 300 8 36.9 3.6 0.8 58.6 0.1 300 700 15 52.2 10.9 1.2 35.6 0.1 350 700 20 45.1 28.7 1.8 24.2 0.2 400 500 10 41.6 43.2 2.6 12.3 0.3 230 500 10 30.1 1.1 0.2 68.5 0.1 330 600 12 36.3 50.2 2.8 10.5 0.2

Embodiment 2

(11) 200 ml of an Al.sub.2O.sub.3/Cr/Mg catalyst (by mass percentage, comprising 90% of Al.sub.2O.sub.3, 8% of Cr.sub.2O.sub.3 and 2% of MgO) is loaded into a first reactor, and the temperature is raised to a bed temperature of 330 C., and HF is introduced for activation at a HF flow rate of 100 g/h and at a hot spot temperature of less than 380 C.; when the hot spot temperature and the bed temperature are the same but no longer raised, the fluorination ends.

(12) The first reactor is heated to the reaction temperature, and HFO-1233zd(Z) is introduced to carry out a reaction, the space velocity of the reactor is maintained at a set value, and after 1 hour of reaction, samples are taken from the outlet of the first reactor for analysis. The reaction results at different temperatures and space velocities are shown in Table 2-1.

(13) TABLE-US-00004 TABLE 2-1 Outlet Organic Composition of the First Reactor in Embodiment 2 Reaction conditions Outlet composition of reactor (%) Temperature Space velocity HFO-1233zd HFO-1233zd ( C.) (h.sup.1) (Z) (E) Other 200 500 55.6 44.3 0.1 250 300 48.6 51.3 0.1 320 800 32.2 67.5 0.3 400 1000 14.5 85.1 0.4 260 500 37.5 62.4 0.1

(14) 200 ml of a Cr.sub.2O.sub.3/ZnO/GaO catalyst (by mass percentage, comprising 90% of Cr.sub.2O.sub.3, 9.5% of ZnO and 0.5% of GaO) is loaded into a second reactor, and the temperature is raised to a bed temperature of 350 C., and HF is introduced for activation at a HF flow rate of 100 g/h and at a hot spot temperature of less than 370 C.; when the hot spot temperature and the bed temperature are the same but no longer raised, the fluorination is further carried out for 20 h and then ends.

(15) After separating the outlet mixture of the first reactor, a product HFO-1233zd(E) with the purity of 99.9% is obtained, and 40 wt % of the product HFO-1233zd(E) is introduced into the second reactor together with HF to carry out reaction; and after 1 hour of reaction, samples are taken from the outlet of the second reactor for analysis. The results of the reaction under the conditions of different temperatures, space velocities, and molar ratios of HF to trans-1-chloro-3,3,3-trifluoropropene are shown in Table 2-2.

(16) TABLE-US-00005 TABLE 2-2 Outlet Organic Composition of the Second Reactor in Embodiment 2 Space Temperature velocity HF/HFO-1233zd HFO-1233zd HFO-1234ze HFO-1234ze ( C.) (h.sup.1) (E) (E) (E) (Z) HFC-245fa Other 180 500 10 50 1.1 0.3 48.5 0.1 200 300 8 30.8 2.7 05 61.4 0.1 300 700 15 51.8 15.6 1.7 30.8 0.1 350 700 20 40.8 37.5 2.5 19 0.2 400 500 10 35.2 51.7 3.2 9.5 0.4 230 500 10 21.3 0.9 0.1 77.6 0.1 330 600 12 25.2 62.1 5.8 6.7 0.2

Embodiment 3

(17) 200 ml of an Al.sub.2O.sub.3/Cr/Mg catalyst (by mass percentage, comprising 93% of Al.sub.2O.sub.3, 6% of Cr.sub.2O.sub.3 and 1% of MgO) is loaded into a first reactor, and the temperature is raised to a bed temperature of 330 C., and HF is introduced for activation at a HF flow rate of 100 g/h and at a hot spot temperature of less than 380 C.; when the hot spot temperature and the bed temperature are the same but no longer raised, the fluorination ends.

(18) The first reactor is heated to the reaction temperature, and HFO-1233zd(Z) is introduced to carry out a reaction, the space velocity of the reactor is maintained at a set value, and after 1 hour of reaction, samples are taken from the outlet of the first reactor for analysis. The reaction results at different temperatures and space velocities are shown in Table 3-1.

(19) TABLE-US-00006 TABLE 3-1 Outlet Organic Composition of the First Reactor in Embodiment 3 Reaction conditions Outlet composition of reactor (%) Temperature Space velocity HFO-1233zd HFO-1233zd ( C.) (h.sup.1) (Z) (E) Other 200 500 67.1 32.8 0.1 250 300 58.4 41.5 0.1 320 800 50.9 48.9 0.2 400 1000 40.1 59.7 0.2 260 500 55.6 44.3 0.1

(20) 200 ml of a Cr.sub.2O.sub.3/ZnO/GaO catalyst (by mass percentage, comprising 73% of Cr.sub.2O.sub.3, 25% of ZnO and 2% of GaO) is loaded into a second reactor, and the temperature is raised to a bed temperature of 350 C., and HF is introduced for activation at a HF flow rate of 100 g/h and at a hot spot temperature of less than 370 C.; when the hot spot temperature and the bed temperature are the same but no longer raised, the fluorination is further carried out for 20 h and then ends.

(21) After separating the outlet mixture of the first reactor, a product HFO-1233zd(E) with the purity of 99.9% is obtained, and 50 wt % of the product HFO-1233zd(E) is introduced into the second reactor together with HF to carry out reaction; and after 1 hour of reaction, samples are taken from the outlet of the second reactor for analysis. The results of the reaction under the conditions of different temperatures, space velocities, and molar ratios of HF to trans-1-chloro-3,3,3-trifluoropropene are shown in Table 3-2.

(22) TABLE-US-00007 TABLE 3-2 Outlet Organic Composition of the Second Reactor in Embodiment 3 Space Temperature velocity HF/HFO-1233zd HFO-1233zd HFO-1234ze HFO-1234ze ( C.) (h.sup.1) (E) (E) (E) (Z) HFC-245fa Other 180 500 10 47.0 1.2 0.4 51.3 0.1 200 300 8 29.3 3.1 0.3 67.2 0.1 300 700 15 50.5 21.3 2.2 25.9 0.1 350 700 20 48.0 44.1 2.1 5.6 0.2 400 500 10 25.1 65.8 2.3 6.5 0.3 230 500 10 24.2 1.2 0.3 74.2 0.1 330 600 12 31.7 60.4 1.5 6.2 0.2

Embodiment 4

(23) 200 ml of an Al.sub.2O.sub.3/Cr/Mg catalyst (by mass percentage, comprising 90% of Al.sub.2O.sub.3, 7% of Cr and 3% of Mg) is loaded into a first reactor, and the temperature is raised to a bed temperature of 330 C., and HF is introduced for activation at a HF flow rate of 100 g/h and at a hot spot temperature of less than 380 C.; when the hot spot temperature and the bed temperature are the same but no longer raised, the fluorination ends.

(24) The first reactor is heated to the reaction temperature, and HFO-1233zd(Z) is introduced to carry out a reaction, the space velocity of the reactor is maintained at a set value, and after 1 hour of reaction, samples are taken from the outlet of the first reactor for analysis. The reaction results at different temperatures and space velocities are shown in Table 4-1.

(25) TABLE-US-00008 TABLE 4-1 Outlet Organic Composition of the First Reactor in Embodiment 4 Reaction conditions Outlet composition of reactor (%) Temperature Space velocity HFO-1233zd HFO-1233zd ( C.) (h.sup.1) (Z) (E) Other 200 500 52.5 47.5 0 250 300 46.1 53.8 0.1 320 800 24.5 75.3 0.2 400 1000 14.2 85.7 0.1 220 500 18.6 81.3 0.1

(26) 200 ml of a Cr.sub.2O.sub.3/ZnO/GaO catalyst (by mass percentage, comprising 85% of Cr.sub.2O.sub.3, 14% of ZnO and 1% of GaO) is loaded into a second reactor, and the temperature is raised to a bed temperature of 350 C., and HF is introduced for activation at a HF flow rate of 100 g/h and at a hot spot temperature of less than 370 C.; when the hot spot temperature and the bed temperature are the same but no longer raised, the fluorination is further carried out for 20 h and then ends.

(27) After separating the outlet mixture of the first reactor, a product HFO-1233zd(E) with the purity of 99.9% is obtained, and 70 wt % of the product HFO-1233zd(E) is introduced into the second reactor together with HF to carry out reaction; and after 1 hour of reaction, samples are taken from the outlet of the second reactor for analysis. The results of the reaction under the conditions of different temperatures, space velocities, and molar ratios of HF to trans-1-chloro-3,3,3-trifluoropropene are shown in Table 4-2.

(28) TABLE-US-00009 TABLE 4-2 Outlet Organic Composition of the Second Reactor in Embodiment 4 Space Temperature velocity HF/HFO-1233zd HFO-1233zd HFO-1234ze HFO-1234ze ( C.) (h.sup.1) (E) (E) (E) (Z) HFC-245fa Other 180 500 10 43.7 0.8 0.2 55.2 0.1 200 300 8 23.2 1.1 0.5 75.1 0.1 300 700 15 17.5 35.3 1.8 45.3 0.1 350 700 20 34.2 51.6 1.6 12.3 0.3 400 500 10 13.8 74.6 1.9 9.6 0.1 230 500 10 13.2 0.9 0.7 85.2 0 350 600 10 4.5 81.2 5.6 8.5 0.2