Reactor and agitator useful in a process for making 1-chloro-3,3,3-trifluoropropene

Abstract

Disclosed are a reactor and agitator useful in a high pressure process for making 1-chloro-3,3,3-trifluoropropene (1233zd) from the reaction of 1,1,1,3,3-pentachloropropane (240fa) and HF, wherein the agitator includes one or more of the following design improvements: (a) double mechanical seals with an inert barrier fluid or a single seal; (b) ceramics on the rotating faces of the seal; (c) ceramics on the static faces of seal; (d) wetted o-rings constructed of spring-energized Teflon and PTFE wedge or dynamic o-ring designs; and (e) wetted metal surfaces of the agitator constructed of a corrosion resistant alloy.

Claims

1. A reactor and agitator useful in a high pressure process for making 1-chloro-3,3,3-trifluoropropene (1233zd) from the reaction of 1,1,1,3,3-pentachloropropane (240fa) and HF, wherein the agitator includes one or more of the following improvements: (a) double mechanical seals with an inert barrier fluid; (b) wherein the rotating faces of the seals comprise ceramic parts or ceramic coatings; (c) wherein the static faces of seal comprise ceramic parts or ceramic coatings; (d) wetted o-rings for the seals are constructed of spring-energized perfluoroelastomer wedge or dynamic o-ring designs; and (e) wetted metal surfaces of the agitator constructed of a corrosion resistant alloy; and wherein the spring-energized perfluoroelastomer wedge comprises the OMNISEAL brand.

2. The reactor and agitator of claim 1, wherein the barrier fluid comprises FLUOROLUBE.

3. The reactor and agitator of claim 1, wherein the ceramic parts or coatings comprise silicon carbide.

4. The reactor and agitator of claim 1, wherein the reactor pressure range is from 150 psig to 600 psig.

5. The reactor and agitator of claim 1, wherein the reactor pressure range is from 230 psig to 500 psig.

6. The reactor and agitator of claim 1, wherein the reactor pressure range is from 350 psig to 450 psig.

7. The reactor and agitator of claim 1, wherein the reactor temperature range is from 90 to 145 C.

8. A reactor and agitator useful in a high pressure process for making 1-chloro-3,3,3-trifluoropropene (1233zd) from the reaction of 1,1,1,3,3-pentachloropropane (240fa) and HF, wherein the agitator includes one or more of the following improvements: (a) double mechanical seals with an inert barrier fluid; (b) wherein the rotating faces of the seals comprise ceramic parts or ceramic coatings; (c) wherein the static faces of seals comprise ceramic parts or ceramic coatings; (d) wherein wetted o-rings for the seals are constructed of spring-energized perfluoroelastomer wedge or dynamic o-ring designs; and (e) wherein wetted metal surfaces of the agitator comprise a corrosion resistant alloy; and wherein the corrosion resistant alloy comprises a nickel alloy.

9. The reactor and agitator of claim 8, wherein the barrier fluid comprises FLUOROLUBE.

10. The reactor and agitator of claim 8, wherein the ceramic parts or coatings comprise silicon carbide.

11. The reactor and agitator of claim 8, wherein the reactor pressure range is from 150 psig to 600 psig.

12. The reactor and agitator of claim 8, wherein the reactor pressure range is from 230 psig to 500 psig.

13. The reactor and agitator of claim 8, wherein the reactor pressure range is from 350 psig to 450 psig.

14. The reactor and agitator of claim 8, wherein the reactor temperature range is from 90 to 145 C.

15. A reactor and agitator useful in a high pressure process for making 1-chloro-3,3,3-trifluoropropene (1233zd) from the reaction of 1,1,1,3,3-pentachloropropane (240fa) and HF, wherein the agitator includes one or more of the following improvements: (a) double mechanical seals with an inert barrier fluid; (b) wherein the rotating faces of the seals comprise ceramic parts or ceramic coatings; (c) wherein the static faces of seals comprise ceramic parts or ceramic coatings; (d) wherein wetted o-rings for the seals are constructed of spring-energized perfluoroelastomer wedge or dynamic o-ring designs; and (e) wherein wetted metal surfaces of the agitator comprise a corrosion resistant nickel alloy; and wherein the nickel alloy is selected from the group consisting of Alloy 20, the HASTELLOY alloys and the INCONEL alloys.

16. The reactor and agitator of claim 15, wherein the barrier fluid comprises FLUOROLUBE.

17. The reactor and agitator of claim 15, wherein the ceramic parts or coatings comprise silicon carbide.

18. The reactor and agitator of claim 15, wherein the reactor pressure range is from 150 psig to 600 psig.

19. The reactor and agitator of claim 15, wherein the reactor pressure range is from 230 psig to 500 psig.

20. The reactor and agitator of claim 15, wherein the reactor pressure range is from 350 psig to 450 psig.

21. The reactor and agitator of claim 15, wherein the reactor temperature range is from 90 to 145 C.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 illustrates a preferred agitator design of the present invention.

(2) FIG. 2 illustrates a preferred continuous stirred tank reactor vessel design of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

(3) As described above, in the high pressure process for the production of 1233zd, the operating conditions of the reactor are extremely aggressive (e.g., 140 C. and 400 psig) and the process employs reactant materials that are highly corrosive under these reaction conditions. The process requires agitation to allow the reaction to proceed. As such, the design of the agitator is critical to ensure an appropriate operating lifetime in the harsh conditions. The present invention is directed to one such reactor and agitator design.

(4) Key Characteristics of Agitator Design

(5) (a) Double mechanical seal with an inert barrier fluid such as fluorolube. (b) Silicon Carbide ceramics (or the like) on the rotating faces of the seal. (c) Silicon Carbide ceramics (or the like) may also be used on the static faces of seal. (d) Perfluoroelastomer o-rings and PTFE wedge design (e) Wetted metal surfaces of the agitator constructed of an appropriate nickel alloy such as Alloy 20, the HASTELLOY alloys or the INCONEL alloys.

(6) As shown in FIG. 1, an agitator according to the present invention includes a double mechanical seal consisting of a ceramic material, e.g., silicon carbide and equivalents, on the rotating faces, wetted parts that are constructed of an appropriate nickel alloy, and spring-energized o-rings. The agitator may be installed in a top or bottom mount position.

(7) As shown in FIG. 2, a reactor vessel according to the present invention includes an agitator of the style of FIG. 1, materials of construction of an appropriate nickel alloy (either solid or clad), and may contain an external or internal heating or cooling system. The design may be modified to feed reactants in the liquid or vapor phase and may be fed to the bottom or top of the vessel.

(8) Corrosion resistant alloys are known and are preferred materials used in the construction of the reactor vessel and agitator of the present invention. Some of the commercially available corrosion resistant alloys include the following:

(9) (a) Nickel 200

(10) Nickel 200 is commercially pure (99.6%) wrought nickel. It has good mechanical properties and excellent resistance to many corrosive environments.

(11) (b) Monel 400

(12) Monel nickel-copper alloy 400 is a solid solution alloy that may be hardened only by cold working. It has high strength and toughness over a wide temperature range and excellent resistance to many corrosive environments.

(13) (c) Inconel 600

(14) Inconel nickel-chromium-iron alloy 600 is a standard engineering material for applications which require resistance to corrosion and heat. The alloy shows resistance to oxidizing conditions at high temperatures or in corrosive solutions.

(15) (d) Inconel 625

(16) Inconel nickel chromium alloy 625 is used for its high strength, excellent fabricability (including joining), and outstanding corrosion resistance.

(17) (e) INCO C-276

(18) INCO alloy C-276 is known for its outstanding corrosion resistance in a wide range of severe media. The high nickel and molybdenum contents provide good corrosion resistance in reducing environments while chromium imparts resistance to oxidizing media.

(19) (f) INCOLOY Alloy 800

(20) INCOLOY alloy 800 is a widely used material of construction for equipment that must have high strength and resist oxidation, carburization, and other harmful effects of high-temperature exposure. The chromium in the alloy imparts resistance to oxidation and corrosion.

(21) (g) INCOLOY 825

(22) INCOLOY alloy 825 is a nickel-iron-chromium alloy with additions of molybdenum, copper and titanium. The alloy's chemical composition is designed to provide exceptional resistance to many corrosive environments.

(23) (h) Alloy 20

(24) INCO Alloy 20 is an austenitic nickel-iron-chromium alloy with additions of copper and molybdenum. The nickel content makes INCO Alloy 20 resistant to chloride-ion stress-corrosion cracking. Copper and molybdenum give resistance to reducing environments. The molybdenum content also provides good resistance to pitting and crevice corrosion. The chromium gives resistance to oxidizing environments.

(25) (i) HASTELLOY

(26) HASTELLOY is the trademark name for a range of twenty two different highly corrosion-resistant metal alloys loosely grouped by the metallurgical industry under the material term superalloys or high-performance alloys. The predominant alloying ingredient is typically the transition metal nickel.

Working Example

(27) An agitator is constructed of Alloy 20 wetted parts and a double mechanical seal with fluorolube barrier fluid, silicon carbide on all seal faces, spring-energized Teflon o-rings and a PTFE wedge system was operated at conditions ranging from 100 to 400 psig and 90 to 145 C. in a process to produce HFCO-1233zd from HF and HCC-240. The agitator operated successfully for several months.

Comparative Example 1

(28) An agitator constructed of Alloy 20 wetted parts and a double mechanical seal with fluorolube barrier fluid, silicon carbide on all seal faces, perfluoroelastomer o-rings and a PTFE wedge system was operated at conditions ranging from 100 to 400 psig and 90 to 145 C. in a process to produce HFCO-1233zd from HF and HCC-240. The agitator seal system failed after 3 weeks of operation due to chemical attack of the perfluoroestomer wetted o-rings.

Comparative Example 2

(29) An agitator constructed of Alloy 20 wetted parts and a double mechanical seal with fluorolube barrier fluid, tungsten carbide on the rotating seal face, perfluoroelastomer o-rings and a PTFE wedge system was operated at conditions ranging from 100 to 150 psig and 90 to 100 C. in a process to produce HFCO-1233zd from HF and HCC-240. The agitator seal system failed after 2 weeks of operation due to failure of the seal faces.

(30) As used herein, the singular forms a, an and the include plural unless the context clearly dictates otherwise. Moreover, when an amount, concentration, or other value or parameter is given as either a range, preferred range, or a list of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. Where a range of numerical values is recited herein, unless otherwise stated, the range is intended to include the endpoints thereof, and all integers and fractions within the range. It is not intended that the scope of the invention be limited to the specific values recited when defining a range.

(31) It should be understood that the foregoing description is only illustrative of the present invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances that fall within the scope of the appended claims.