Production of improved compositions from 1-chloro-3,3,3-trifluoropropene (HFO-1233ZD) high boiling residual by-products

Abstract

The high-boiling fluorinated by-products obtained from the process for the manufacture of 1-chloro-3,3,3-trifluoropropene (HFO-1233zd) not only contain components that may be used as starting materials or feedstocks in the manufacture of 1,1,1,3,3-pentafluoropropane (HFC-245fa), but also contain impurities that may be harmful in the HFC-245fa process. A method for providing an improved composition from the high-boiling by-products obtained from the HFO-1233zd manufacturing process reduces these impurities. The improved composition can be used as a starting material or feedstock for the manufacture of HFC-245fa.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application is an international application of U.S. Patent Application No. 18 / 083,237, filed December 16, 2022, and claims priority to U.S. Provisional Patent Application No. 63 / 331,970, filed April 18, 2022, and International Application No. CN / 2022 / 073913, filed January 26, 2022, all of which are incorporated by reference in their entireties herein.

[0002] FIELD OF THEINVENTION The present disclosure relates to a process for preparing an improved composition comprising a fluorinated by-product from a process for producing 1-chloro-3,3,3-trifluoropropene (HFO-1233zd), which can be used in the production of 1,1,1,3,3-pentafluoropropane (HFC-245fa). [Background technology]

[0003] Chlorofluorocarbons (CFCs), such as trichlorofluoromethane and dichlorodifluoromethane, have been used as refrigerants, blowing agents, and diluents for gas sterilization. In recent years, there has been widespread concern that certain chlorofluorocarbons may be harmful to the earth's ozone layer. Therefore, there has been a global effort to use halocarbons that contain fewer or no chlorine substituents. Thus, the production of hydrofluorocarbons, or compounds that contain only carbon, hydrogen, and fluorine, is a subject of increasing interest to provide environmentally desirable products for use as solvents, blowing agents, refrigerants, cleaning agents, aerosol propellants, heat transfer media, dielectrics, fire extinguishing compositions, power cycle working fluids, and starting materials for producing hydrofluoroolefins that do not harm the ozone layer and have low global warming potential.

[0004] In this regard, 1,1,1,3,3-pentafluoropropane (HFC-245fa) and 1-chloro-3,3,3-trifluoropropene (HFO-1233zd) are compounds that have the potential to be used as zero ozone depletion potential (ODP) and low global warming potential (GWP) refrigerants, blowing agents, aerosol propellants, insulation materials, solvents, etc., as well as starting materials for E-1,1,1,3-tetrafluoropropene, HFO-1234ze (E).

[0005] U.S. Patent Nos. 9,045,386 and 5,574,192 describe processes for producing 1-chloro-3,3,3-trifluoropropene (HFO-1233zd) and 1,1,1,3,3-pentafluoropropane (HFC-245fa) in high purity on a commercial scale, respectively, and are incorporated herein by reference.

[0006] It has been found that certain high boiling residues or by-products are produced in the HFO-1233zd manufacturing process. These by-products are produced in significant quantities and uses other than disposal are desirable. Summary of the Invention

[0007] This disclosure is based on the discovery that the high boiling fluorinated by-products obtained from the HFO-1233zd manufacturing process not only contain components that can be used as starting materials or feedstocks in the production of HFC-245fa, but also contain impurities that can be harmful in the HFC-245fa process. This disclosure is directed to providing improved compositions from the high boiling by-products obtained from the HFO-1233zd manufacturing process by reducing these impurities. The improved compositions can be used as starting materials or feedstocks for the production of HFC-245fa, as well as, optionally, for other applications, such as, for example, producing other hydrofluoroolefins. [Brief description of the drawings]

[0008] The above-mentioned and other features of the present disclosure, as well as the manner in which they are achieved, will become more apparent, and the disclosure itself will be better understood, by referring to the following description of the embodiments of the present disclosure in light of the accompanying drawings, in which: [Figure 1] FIG. 1 shows a schematic diagram of a distillation apparatus including a vaporizer and partial condenser useful for purification of HFO-1233zd high boiling by-products to produce improved compositions. [Diagram 2] FIG. 1 shows a schematic diagram of a distillation apparatus including a vaporizer, a distillation column, and a total condenser useful for the purification of HFO-1233zd high boiling by-products to produce improved compositions.

[0009] The exemplifications set forth herein illustrate embodiments of the present disclosure, and such exemplifications should not be construed as limiting the scope of the present disclosure in any way. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] This disclosure is based on the discovery that the high boiling fluorinated by-products obtained from the HFO-1233zd manufacturing process not only contain components that can be used as starting materials or feedstocks in the production of HFC-245fa, but also contain impurities that can be detrimental in the HFC-245fa process. This disclosure is directed to providing improved compositions from the high boiling by-products obtained from the HFO-1233zd manufacturing process by reducing these impurities. The improved compositions can be used as starting materials or feedstocks for the production of HFC-245fa.

[0011] HFO-1233zd can be produced industrially by the reaction shown in Equation 1 below. Formula 1: HCC-240fa+3HF→HFO-1233zd+4HCl

[0012] In this process, 1-chloro-3,3,3-trifluoropropene (HFO-1233zd) can be produced in a liquid phase reaction without the need for a catalyst. Briefly, anhydrous hydrogen fluoride (HF) can be mixed with 1,1,1,3,3-pentachloropropene (HCC-240fa) at elevated temperature and pressure to produce the desired 1-chloro-3,3,3-trifluoropropene (HFO-1233zd) as a mixture of E and Z isomers.

[0013] During the course of the reaction, partially fluorinated by-products such as 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), 1,3,3-trichloro-1,1-difluoropropane (HCFC-242fa), 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243fa), and 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244fa), isomers of HCFC-241fa, 242fa, 243fa, 244fa, and other minor components (e.g., 1,1,3-trichloro-1-fluoropropene and 1,3-dichloro-1,1-difluoropropene, etc.) may be produced according to the formulas 2 to 5 shown below. Formula 2: HCC-240fa+HF→HCFC-241fa+HCl Formula 3: HCC-240fa+2HF→HCFC-242 isomer+2HCl Formula 4: HCC-240fa+3HF→HCFC-243 isomer+3HCl Formula 5: HCC-240fa+4HF→HCFC-244 isomer+4HCl

[0014] The mixture of high-boiling fluorinated components may be defined as a mixture of high-boiling by-products, meaning fluorinated components having a boiling point higher than 39° C., in other words higher than the boiling point of Z-1-chloro-3,3,3-trifluoropropene (HFO-1233zd(Z)).

[0015] Other by-products that may be present in the feed stream or reactor stream include oligomers. As used herein, oligomers can be defined as dimers, trimers, tetramers, and other groups of repeating and / or mixed monomer units that cannot be readily converted to 1-chloro-3,3,3-trifluoropropene (HFO-1233zd) using the methods described herein.

[0016] Other impurities that may be present in the reactor as by-products include very high boiling components, which as used herein means impurities with boiling points above about 140.2°C, which is the normal boiling point of HCFC-241fa. These very high boiling components may include CC-110 (hexachloroethane), halogenated hydrocarbons with 5 or more carbon atoms, and some oligomers. For example, a possible very high boiling oligomer may be a dimer of 1,3,3-trichloro-3-fluoropropene (HCFO-1231zd) and 1,3-dichloro-3,3-difluoropropene (HCFO-1232zd), which has the chemical formula CHFCl. Very high boiling components may also include small amounts of olefinic components such as 1,1,3-trichloro-1-fluoropropene and 1,3-dichloro-1,1-difluoropropene. For purposes of this invention, these very high boiling components, such as CC-110, halogenated hydrocarbons having 5 or more carbon atoms, oligomers, and small amounts of olefinic components, may also be referred to as heavy impurities.

[0017] Because both the processes for producing HFO-1233zd and HFC-245fa utilize similar feedstocks, the HFO-1233zd process by-products produced by Reactions 2-5 are useful as precursors in the production of HFC-245fa. These HFO-1233zd high boiling by-products can be fed to the HFC-245fa reactor along with HF and optionally 1,1,1,3,3-pentachloropropane (HCC-240fa). The ability to use the by-products of the HFO-1233zd process to produce HFC-245fa greatly improves the efficiency of the process.

[0018] It has been found that when high boiling fluorinated by-products are fed to the HFC-245fa reactor, the catalyst activity decreases faster than when only HCC-240fa is used. It is believed that the decrease in capacity may be caused by impurities including very high boiling fluorinated components and heavy impurities in the HFO-1233zd by-product. Furthermore, hexachloroethane (CC-110) in particular has been found to cause the formation of solids in the HFC-245fa reactor system, which results in the need to periodically shut down and clean the system, resulting in reduced production.

[0019] US Patent No. 5,574,192 discloses the use of components present in the HFO-1233zd high boiling by-product in the HFC-245fa manufacturing process to produce HFC-245fa. However, this patent teaches the use of components present in the HFO-1233zd high boiling by-product in the HFC-245fa manufacturing process without any pretreatment or purification, such as mitigating the very high boiling by-product, in accordance with the present teachings. No drawbacks, such as loss of catalytic activity, resulting from using the HFO-1233zd high boiling by-product in this manner are suggested. This reduction in catalytic activity and the formation of solids in the liquid phase HFC-245fa process result in reduced production capacity and higher catalyst replacement costs.

[0020] The present disclosure alleviates these shortcomings by treating the HFO-1233zd high boiling by-products prior to use in the HFC-245fa reactor to remove or minimize the very high boiling by-products. This treatment converts the by-product composition into an improved feedstock for HFC-245fa by removing very high boiling fluorinated components and heavy impurities. Separation of these very high boiling impurities from useful under-fluorinated by-products including 1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), 1,3,3-trichloro-1,1-difluoropropane (HCFC-242fa), 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243fa), and 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244fa) along with their isomers. For example, one of the 242fa isomers is 1,1,3-trichloro-1,3-difluoropropane (HCFC-242fb) and one of the 243fa isomers is 1,3-dichloro-1,1,3-trifluoropropane (HCFC-243fb). Recycling these useful by-products allows for more efficient HFO-245fa production without reducing the catalytic activity of the HFO-245fa reactor or plant capacity.

[0021] The present disclosure may be practiced by subjecting the high boiling fluorinated by-products from the production of 1-chloro-3,3,3-trifluoropropene (HFO-1233zd) to distillation to produce improved compositions containing isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), in very low concentrations in hexachloroethane and other very high boiling components having boiling points higher than that of HCFC-241fa.

[0022] The resulting composition, which may be used as a feedstock for the production of HCFC-245fa, may comprise at least one component selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), together in a combined amount of 50 wt.% or more, 75 wt.% or more, or 90 wt.% or more, based on the total weight of the composition.

[0023] The resulting composition, which may be used as a feedstock for the production of HCFC-245fa, may also contain very high boiling fluorinated components and / or heavy impurities in a combined amount of 5 wt.% or less, 1 wt.% or less, 0.5 wt.% or less, or 0.1 wt.% or less, based on the total weight of the composition.

[0024] The resulting composition, which can be used as a feedstock for the production of HCFC-245fa, may contain, inter alia, less than 1.0 wt.%, less than 0.5 wt.%, less than 0.3 wt.%, less than 0.1 wt.%, or less than 0.01 wt.% hexachloroethane (CC-110).

[0025] In one option, the distillation apparatus may be a two-stage distillation consisting of a vaporizer and a partial condenser that separates the HFO-1233zd high boiling components and heavy impurities from the upgraded composition that is fed to the HFC-245fa reactor.

[0026] One example of this process is shown in Figure 1 and summarized below. As shown therein, the HFO-1233zd high boiling by-product stream may enter the unit as a liquid 10 or as a vapor 12. Feed stream 10 is fed to a partial vaporizer 16, and feed stream 12 is fed to a partial condenser 18.

[0027] From the vaporizer 16, an effective amount of heat energy is added to the liquid HFO-1233zd high boiling by-product to form a vapor stream 17 which is sent to a partial condenser 18. The partial condenser 18 is at a temperature effective to partially condense the incoming vapor at a desired pressure to produce a liquid 19 which is returned to the vaporizer 16 as reflux.

[0028] From the partial condenser 18, a vapor distillate stream 22 having reduced levels of very high boiling components flows into a total condenser 24 and is pumped to provide an improved composition or liquid feed stream 25 containing isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), along with low levels of very high boiling fluorinated components, heavy impurities, or any other impurities having a boiling point higher than HCFC-241fa, as described above.

[0029] Feed stream 25 then enters HFC-245fa reactor 26. HFC-245fa reactor 26 is fed HCC-240fa from stream 28 and HF from stream 30. HFC-245fa reactor product 32 may then be removed.

[0030] A liquid waste stream 14 containing the very high boiling fluorinated components, heavy impurities, or any other impurities having a boiling point higher than HCFC-241fa may then be removed for disposal or further recovery of useful components.

[0031] The vaporizer 16 may operate at temperatures of 90° C. or more, 95° C. or more, 100° C. or more, 105° C. or more, 115° C. or more, 125° C. or more, 135° C. or more, 185° C. or less, 175° C. or less, 165° C. or less, 155° C. or less, or any range inclusive of these endpoints.

[0032] The distributor 18 may operate at temperatures of 80° C. or more, 105° C. or more, 150° C. or more, 160° C. or more, 170° C. or less, 150° C. or less, 125° C. or less, 100° C. or less, or any range inclusive of these endpoints.

[0033] The composition in feed stream 10 or 12 may contain from about 1% to about 40% by weight of the HCFC-241fa isomer, from about 10% to about 35% by weight of the HCFC-241fa isomer, from about 20% to about 30% by weight of the HCFC-241fa isomer, or about 25% by weight of the HCFC-241fa isomer. Feed stream 10 or 12 may also contain from about 40% to about 80% by weight of the HCFC-242 isomer, from about 54% to about 74% by weight of the HCFC-242 isomer, from about 59% to about 69% by weight of the HCFC-242 isomer, or about 64% by weight of the HCFC-242 isomer. Feed stream 10 or 12 may also contain up to about 21 wt% HCFC-243 isomers, up to about 16 wt% HCFC-243 isomers, up to about 11 wt% HCFC-243 isomers, or up to about 6% HCFC-243 isomers. Feed stream 10 or 12 may also contain up to about 15 wt% HCFC-244 isomers, up to about 10 wt% HCFC-244 isomers, up to about 5 wt% HCFC-244 isomers, or up to about 0.26 wt% HCFC-244 isomers. Feed stream 10 or 12 may also contain up to about 15 wt% hexachloroethane, up to about 10 wt% hexachloroethane, up to about 5 wt% hexachloroethane, or up to about 0.44 wt% hexachloroethane.

[0034] The improved composition of feed stream 22 may include from about 1% to about 40% by weight of the HCFC-241fa isomer, from about 10% to about 35% by weight of the HCFC-241fa isomer, or from about 20% to about 30% by weight of the HCFC-241fa isomer. Feed stream 22 may also include from about 40% to about 80% by weight of the HCFC-242 isomer, from about 54% to about 74% by weight of the HCFC-242 isomer, or from about 59% to about 69% by weight of the HCFC-242 isomer. Feed stream 22 may also include up to about 21% by weight of the HCFC-243 isomer, up to about 16% by weight of the HCFC-243 isomer, or up to about 11% by weight of the HCFC-243 isomer. Feed stream 22 may also contain up to about 15% by weight of HCFC-244 isomers, up to about 10% by weight of HCFC-244 isomers, or up to about 5% by weight of HCFC-244 isomers.

[0035] The improved composition of stream 22 may also contain very high boiling fluorinated components and / or heavy impurities in an amount of 5 wt.% or less, 1 wt.% or less, 0.5 wt.% or less, or 0.1 wt.% or less, based on the total weight of the composition.

[0036] The improved composition of stream 22 may also include, and may specifically contain, less than 1.0 wt.%, less than 0.5 wt.%, less than 0.3 wt.%, less than 0.1 wt.%, or less than 0.01 wt.% hexachloroethane (CC-110).

[0037] In another option, the distillation apparatus may be a multi-stage distillation, which includes a column between the vaporizer and the condenser that increases the number of stages of distillation to allow for a desired result with less heat energy input to the vaporizer, the column being equipped with packings or trays known and readily available in the art for carrying out the distillation.

[0038] An example process is shown in Figure 2 and summarized below. As shown therein, HFO-1233zd high boiling by-product feed stream 40 enters a multi-stage distillation process. The addition of a distillation column 46 between reboiler 42 and condenser 50 allows condenser 50 to function as a total condenser instead of a partial condenser. From the reboiler, vapor stream 43 enters distillation column 46. Reflux from the distillation column is returned to the reboiler via stream 41. Overhead vapor stream 47 enters total condenser 50, which operates at a temperature effective to condense the distillate at the desired pressure.

[0039] Total condenser 50 provides stream 54. From the total condenser, stream 54 flows into pump 56. The remainder of the liquid is returned to the column as reflux via stream 48.

[0040] Pump 56 delivers the improved composition or liquid feed stream 57 containing isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), along with low levels of very high boiling fluorinated components, heavy impurities, or any other impurities having a higher boiling point than HCFC-241fa, to HFC-245fa reactor 58, with HF provided by feed stream 62 and HCC-240fa provided by feed stream 64. HFC-245fa reactor product 60 may then be removed.

[0041] A liquid waste stream 44 containing the very high boiling fluorinated components, heavy impurities, or any other impurities having a boiling point higher than HCFC-241fa may then be removed for disposal or further recovery of useful components.

[0042] Reboiler 42 may operate at a temperature of about 130° C. or more, about 140° C. or more, about 150° C. or more, about 160° C. or more, about 210° C. or less, about 200° C. or less, about 190° C. or less, about 180° C. or less, or any range inclusive of these endpoints.

[0043] Distillation column or tower 46 may operate at a temperature of 0° C. or more, 10° C. or more, 20° C. or more, 30° C. or more, 50° C. or less, 60° C. or less, 70° C. or less, 80° C. or less, or any range inclusive of these endpoints.

[0044] The total condenser 50 may operate at a temperature of 80° C. or more, 90° C. or more, 100° C. or more, 110° C. or more, 130° C. or less, 140° C. or less, 150° C. or less, 160° C. or less, or any range inclusive of these endpoints.

[0045] The composition in feed stream 40 may contain from about 10% to about 40% by weight of the HCFC-241 isomer, from about 15% to about 35% by weight of the HCFC-241 isomer, from about 20% to about 30% by weight of the HCFC-241 isomer, or about 25% by weight of the HCFC-241 isomer. Feed stream 40 may also contain from about 49% to about 79% by weight of the HCFC-242 isomer, from about 54% to about 74% by weight of the HCFC-242 isomer, from about 59% to about 69% by weight of the HCFC-242 isomer, or about 64% by weight of the HCFC-242 isomer. Feed stream 40 may also contain up to about 21% by weight of HCFC-243 isomers, up to about 16% by weight of HCFC-243 isomers, up to about 11% by weight of HCFC-243 isomers, or up to about 6% by weight of HCFC-243 isomers. Feed stream 40 may also contain up to about 15% by weight of HCFC-244 isomers, up to about 10% by weight of HCFC-244 isomers, up to about 5% by weight of HCFC-244 isomers, or up to about 0.26% by weight of HCFC-244 isomers.

[0046] Feed stream 40 may also contain up to about 15% by weight hexachloroethane, up to about 10% by weight hexachloroethane, up to about 5% by weight hexachloroethane, or up to about 0.44% by weight hexachloroethane.

[0047] Feed stream 40 may also contain up to about 15% by weight heavy impurities, up to about 10% by weight heavy impurities, up to about 5% by weight heavy impurities, or up to about 0.24% by weight heavy impurities.

[0048] Feed stream 40 may also contain up to about 20% by weight of other components, up to about 15% by weight of other components, up to about 10% by weight of other components, or up to about 4.25% by weight of other components, which may include, but are not limited to, other impurities including isomers of 1,1,1,3,3-pentachloropropane (HCC-240fa), 1,3,3-trichloro-3-fluoro-1-ene (HFO-1231) and 2,3-dichloro-3,3-difluoropropene (HFO-1232), isomers of 1,1,1,3,3-pentafluoropropane (HFC-245fa), isomers of 1-chloro-3,3,3-trifluoropropene (HFO-1233zd), and oligomers having boiling points close to or lower than 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa).

[0049] The improved composition in feed stream 54 may contain from about 10% to about 40% by weight of the HCFC-241 isomer, from about 15% to about 35% by weight of the HCFC-241 isomer, or from about 20% to about 30% by weight of the HCFC-241 isomer. Feed stream 54 may also contain from about 49% to about 79% by weight of the HCFC-242 isomer, from about 54% to about 74% by weight of the HCFC-242 isomer, or from about 59% to about 69% by weight of the HCFC-242 isomer. Feed stream 54 may also contain up to about 21% by weight of the HCFC-243 isomer, up to about 16% by weight of the HCFC-243 isomer, or up to about 11% by weight of the HCFC-243 isomer. Feed stream 54 may also contain up to about 15% by weight of HCFC-244 isomers, up to about 10% by weight of HCFC-244 isomers, or up to about 5% by weight of HCFC-244 isomers.

[0050] The improved composition of stream 54 may also contain very high boiling fluorinated components and / or heavy impurities in a combined amount of 50 wt.% or less, 25 wt.% or less, 10 wt.% or less, 5 wt.% or less, or 1 wt.% or less, based on the total weight of the composition.

[0051] The improved composition of stream 54 may also include, and may specifically contain, less than 1.0 wt.%, less than 0.5 wt.%, less than 0.3 wt.%, less than 0.1 wt.%, or less than 0.01 wt.% hexachloroethane (CC-110).

[0052] The distillation in either option may be carried out at a pressure of 5 bar or less, 4 bar or less, 3 bar or less, 2 bar or less, 1 bar or less, vacuum, or any range inclusive of these endpoints.

[0053] The heating system in either option may include any suitable heating medium capable of achieving and / or maintaining the temperature required for the process. Suitable heating media may include, for example, molten salts, hot oil, high pressure steam, and electric heaters (resistance or induction), among others.

[0054] Fluorination catalysts useful in reactor 26 or 58 include (I) pentavalent antimony, niobium, arsenic, and tantalum halides; (II) pentavalent antimony, niobium, arsenic, and tantalum mixed halides; and (III) mixtures of pentavalent antimony, niobium, arsenic, and tantalum halide catalysts. Examples of group (I) catalysts include antimony pentachloride and antimony pentafluoride. Examples of group (II) catalysts include SbCl2F3 and SbBr2F3. Examples of group (III) catalysts include mixtures of antimony pentachloride and antimony pentafluoride.

[0055] Other suitable catalysts may include chromium oxide, chromium oxyfluoride, and chromium halides. Chromium oxide may include amorphous chromium oxide (Cr2O3), crystalline chromium oxide, and combinations thereof. Chromium oxyfluoride may include fresh amorphous chromium oxide (Cr2O3) pretreated with HF, fresh crystalline chromium oxide (Cr2O3) pretreated with HF, amorphous chromium oxyfluoride (CrO x F y(wherein x may be greater than 0 but less than 1.5, and y may be greater than 0 but less than 3), crystalline chromium oxyfluoride (CrO x F y (wherein x may be greater than 0 but less than 1.5, and y may be greater than 0 but less than 3), and combinations thereof. In one embodiment, the catalyst may include amorphous chromium oxyfluoride (CrO x F y where x can be greater than 0 but less than 1.5, and y can be greater than 0 but less than 3. Chromium halides can include chromium trifluoride (CrF3), chromium trichloride (CrCl3), chromium triiodide (CrI3), and chromium tribromide (CrBr3), and combinations thereof. In one embodiment, the catalyst is chromium trifluoride (CrF3).

[0056] Other suitable catalysts include chromium-based promoted catalysts, which are based on chromium and contain an amount of at least one cocatalyst selected from Ni, Zn, Co, Mn, Mg, or mixtures thereof. The amount of cocatalyst may be 0.1% to 20% by weight based on the total weight of the catalyst, and more specifically may be present in an amount as small as 0.1%, 0.5%, 1.0%, 1.5% or as large as 2.0%, 3.0%, 4.0%, 5.0%, 6.0% by weight based on the total weight of the catalyst, or in any range using any two of these values ​​as endpoints. One suitable chromium promoted catalyst is a zinc / chromia catalyst, which is based on chromia and contains an amount of zinc as a cocatalyst, such as the JM 62-3M catalyst available from Johnson Matthey. Prior to use, the catalyst may be fluorinated using anhydrous HF under conditions effective to convert some metal oxides to the corresponding metal fluorides.

[0057] The chromium-based catalyst may also be a low chromium (VI) catalyst having a total chromium (VI) oxide content of about 5000 ppm or less, about 2000 ppm or less, about 1,000 ppm or less, about 500 ppm or less, about 250 ppm or less, or about 100 ppm or less based on the total chromium oxide in the chromium oxide catalyst.

[0058] In addition to chromium-based catalysts, other suitable catalysts include alumina, iron oxide, magnesium oxide, zinc oxide, nickel oxide, cobalt oxide, aluminum fluoride or metal fluorides such as iron fluoride, magnesium fluoride, zinc fluoride, nickel fluoride, cobalt fluoride, fluorinated alumina, fluorinated iron oxide, fluorinated magnesium oxide, fluorinated nickel oxide, fluorinated cobalt oxide, titanium fluoride, molybdenum fluoride, aluminum oxyfluoride, and combinations thereof. Prior to use, catalysts containing metal oxides may be fluorinated using anhydrous HF under conditions effective to convert some of the metal oxides to the corresponding metal fluorides. Pentavalent antimony, niobium, arsenic, and tantalum halides are commercially available, and their mixed halides are generated in situ upon reaction with HF. Antimony pentachloride is preferred due to its low cost and availability. Pentavalent antimony mixed halides of the formula SbClnF5-n, where n is 0 to 5, are more preferred. The fluorination catalyst preferably has a purity of at least about 97%. The amount of fluorination catalyst used can vary widely, but it is suitable to use about 5 to about 50% by weight, or preferably about 10 to about 25% by weight, of catalyst relative to the organic matter. EXAMPLES

[0059] Example 1 Two-stage distillation of high-boiling fluorinated HFO-1233zd by-products In Example 1, a two-stage distillation was carried out using the apparatus shown generally in Figure 1. The distillation experiment was repeated at several pressures and reflux ratios. The results are summarized in Tables 1-6 below.

[0060] The final heading "Other" in each table may include other impurities including, but not limited to, isomers of 1,1,1,3,3-pentachloropropane (HCC-240fa), 1,3,3-trichloro-3-fluoro-1-ene (HFO-1231) and 2,3-dichloro-3,3-difluoropropene (HFO-1232), isomers of 1,1,1,3,3-pentafluoropropane (HFC-245fa), isomers of 1-chloro-3,3,3-trifluoropropene (HFO-1233zd), and oligomers with boiling points close to or lower than 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa).

[0061] [Table 1]

[0062] Table 1 summarizes the data from a two-stage distillation at 1 bar and a reflux ratio of 10:1, with about 2.6% of the feed being removed in the bottoms stream 14. The vaporizer temperature is set at 129° C. At this temperature, most of the high boiling oligomers are in the bottoms, while only about 43% of the hexachloroethane is in the bottoms. Increasing the reflux ratio did not improve the results significantly.

[0063] [Table 2]

[0064] Table 2 summarizes the data from a two-stage distillation at 1 bar and a reflux ratio of 10:1, with about 20% of the feed being removed in bottom stream 14. The vaporizer temperature is set at 121° C. At this temperature, most of the high boiling oligomers are in the bottoms. Increasing the reflux ratio did not improve the results much, but increasing the bottoms stream to about 20% of the feed resulted in more than 90% of the hexachloroethane being sent to the bottoms. In this case, additional recovery of useful materials such as HCFC-241fa and HCFC-242 isomers may be affected by further distillation of stream 14, possibly under vacuum to allow a reduction in temperature.

[0065] [Table 3]

[0066] Table 3 summarizes the data from a two-stage distillation at 3 bar and a 20:1 reflux ratio, with about 2.6% of the feed being removed in the bottom stream 14. The vaporizer temperature is set at 172° C. At this temperature, most of the high-boiling oligomers are at the bottom, while only about 36% of the hexachloroethane is at the bottom. The results suggest that the higher pressure of 3 bar is not favorable for separation. Compared to the experiment carried out at 1 bar, the removal of hexachloroethane from the bottom was worse, even with a double reflux ratio of 20:1.

[0067] [Table 4]

[0068] Table 4 summarizes the data from a two-stage distillation at 3 bar and a reflux ratio of 20:1, with about 25% of the feed being removed in bottom stream 3. The vaporizer temperature is set at 163° C., lower than that in Table 3, due to the high proportion of low boiling components such as HCFC-242 isomers. In this case, most of the high boiling oligomers are in the bottoms. Increasing the reflux ratio did not improve the results much, but increasing the bottoms stream to about 25% of the feed resulted in more than 90% of the hexachloroethane being sent to the bottoms. Additional recovery of useful materials (such as HCFC-241fa and HCFC-242 isomers) may be affected by further distillation of stream 3, possibly under vacuum to allow a reduction in temperature.

[0069] Example 2 Multi-stage distillation of high boiling fluorinated HFO-1233zd by-products In Example 2, a multi-stage distillation was carried out using the apparatus shown generally in Figure 2. The distillation experiment was repeated at several pressures and reflux ratios. The results are shown in Tables 5 and 6 below.

[0070] The final heading "Other" in each table may include other impurities including, but not limited to, isomers of 1,1,1,3,3-pentachloropropane (HCC-240fa), 1,3,3-trichloro-3-fluoro-1-ene (HFO-1231) and 2,3-dichloro-3,3-difluoropropene (HFO-1232), isomers of 1,1,1,3,3-pentafluoropropane (HFC-245fa), isomers of 1-chloro-3,3,3-trifluoropropene (HFO-1233zd), and oligomers with boiling points close to or lower than 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa).

[0071] [Table 5]

[0072] Table 5 summarizes data from a multi-stage distillation at 1 bar and a reflux ratio of 0.5:1, with approximately 2.6% of the feed being removed in bottoms stream 44. Because the lower boiling HCFC-242 isomers are scarce, the vaporizer temperature is set at 146° C., higher than in Table 1. At this temperature, most of the higher boiling oligomers and hexachloroethane are in the bottoms. It may be possible to further distill bottoms stream 44 to recover more of the useful HCFC-241fa isomers, however, it should also be recognized that at high enough concentrations, the hexachloroethane and oligomers may form a solid phase when the stream is cooled.

[0073] [Table 6]

[0074] Table 6 summarizes data from a multi-stage distillation at 3 bar and a reflux ratio of 0.5:1, with about 2.6% of the feed being removed in bottoms stream 44. Because the lower boiling HCFC-242 isomers are scarce, the vaporizer temperature is set at 193° C., higher than in Table 3. At this temperature, most of the higher boiling oligomers and hexachloroethane are in the bottoms. It may be possible to further distill bottoms stream 44 to recover more of the useful HCFC-241fa isomers, however, it should also be recognized that at high enough concentrations, the hexachloroethane and oligomers may form a solid phase when the stream is cooled.

[0075] Examples 3 to 27 Production of HFC-245fa The feedstreams produced according to Examples 1 and 2 are introduced into an HFC-245fa reactor and catalytically reacted with HF to form HFC-245fa in suitable yields and selectivities. The catalysts used in the reactions are shown in Table 7 below for Examples 3-27.

[0076] [Table 7]

[0077] Aspects Embodiment 1 is a composition useful as a feedstock for the production of HFC-245fa, comprising at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), wherein the combined amount of said compounds is 50 wt.% or greater, based on the total weight of the composition; and at least one very high boiling component, wherein all of the very high boiling components are present in a combined amount of 1 wt.% or less, based on the total weight of the composition.

[0078] Example 2 is the composition of example 1, wherein the at least one very high boiling component comprises a mixture of fluorinated components having a boiling point greater than about 140.2°C.

[0079] Example 3 is the composition of example 1 or example 2, wherein the at least one very high boiling component comprises at least one of hexachloroethane and a halogenated hydrocarbon having 5 or more carbon atoms.

[0080] Example 4 is the composition of any of Examples 1-3, wherein the at least one very high boiling component is present in a combined amount less than or equal to 0.5 wt.%, based on the total weight of the composition.

[0081] Example 5 is the composition of any of Examples 1-4, wherein the at least one very high boiling component comprises hexachloroethane in an amount less than 0.3 weight percent, based on the total weight of the composition.

[0082] Example 6 is the composition of any of Examples 1-5, wherein the at least one very high boiling component comprises hexachloroethane in an amount less than 0.1 weight percent, based on the total weight of the composition.

[0083] Aspect 7 is the composition of any one of Aspects 1-6, wherein the combined amount of at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244) is 85 wt% or greater, based on the total weight of the composition.

[0084] Aspect 8 is the composition of any one of Aspects 1-7, wherein the combined amount of at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244) is 95 wt% or greater, based on the total weight of the composition.

[0085] Aspect 9 is a method for producing a composition useful as a feedstock for the production of HFC-245fa, comprising at least partially condensing a composition comprising at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), and at least one very high boiling component, to produce 1,1,3,3 forming a vaporized stream comprising at least one compound selected from the group consisting of isomers of 1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), and a liquid stream comprising the at least one very high boiling component; separating the vaporized stream from the liquid stream; and optionally feeding the vaporized stream to an HFC-245 reactor.

[0086] Example 10 is the method of example 9, wherein the vaporized stream comprises at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), wherein the combined amount of said compounds is 50 wt% or more, based on the total weight of the composition, and at least one very high boiling component, wherein all of the very high boiling components are present in a combined amount of 1 wt% or less, based on the total weight of the composition.

[0087] Example 11 is the method of example 9 or example 10, wherein the at least one very high boiling component is present in a combined amount of less than or equal to 0.5 wt.%, based on the total weight of the vaporized stream.

[0088] Example 12 is the method of any of Examples 9-11, wherein the at least one very high boiling component comprises hexachloroethane in an amount less than 0.3 wt.%, based on the total weight of the vaporized stream.

[0089] Example 13 is the method of any of Examples 9-12, wherein the at least one very high boiling component comprises hexachloroethane in an amount less than 0.1 wt.%, based on the total weight of the vaporized stream.

[0090] Example 14 is the method of any of Examples 9-13, wherein the at least one very high boiling component comprises a mixture of fluorinated components having a boiling point greater than about 140.2 °C.

[0091] Embodiment 15 is a process for producing a composition useful as a feedstock for the production of HFC-245fa, comprising distilling a composition comprising at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), and very high boiling components to produce a distillate stream and a very high boiling component stream, and optionally feeding the distillate stream to an HFC-245 reactor.

[0092] Example 16 is the method of example 15, wherein the distillate stream comprises at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), wherein the combined amount of said compounds is 50 wt% or greater, based on the total weight of the composition; and at least one very high boiling component, wherein all of the very high boiling components are present in a combined amount of 1 wt% or less, based on the total weight of the distillate stream.

[0093] Example 17 is the method of example 15 or example 16, wherein the at least one very high boiling component comprises a mixture of fluorinated components having a boiling point greater than about 140.2 °C.

[0094] Example 18 is the method of any of Examples 15-17, wherein the at least one very high boiling component is present in a combined amount less than or equal to 0.5 wt.%, based on the total weight of the distillate stream.

[0095] Example 19 is the method of any of Examples 15-18, wherein the at least one very high boiling component comprises hexachloroethane in an amount less than 0.3 wt.%, based on the total weight of the distillate stream.

[0096] Example 20 is the method of any of Examples 15-19, wherein the at least one very high boiling component comprises hexachloroethane in an amount less than 0.1 wt.%, based on the total weight of the distillate stream.

[0097] Example 21 is the method of any of Examples 1-20, further comprising the additional step of catalytically reacting the composition with a catalyst selected from alumina, iron oxide, magnesium oxide, zinc oxide, nickel oxide, cobalt oxide, aluminum fluoride, iron fluoride, magnesium fluoride, zinc fluoride, nickel fluoride, cobalt fluoride, fluorided alumina, fluorided iron oxide, fluorided magnesium oxide, fluorided nickel oxide, fluorided cobalt oxide, titanium fluoride, molybdenum fluoride, aluminum oxyfluoride, and combinations thereof to form HFC-245fa.

[0098] Example 22 is the method of any of Examples 1-20, further comprising the additional step of catalytically reacting the composition to form HFC-245fa using a zinc / chromium catalyst having from 0.5 to 6.0 wt. % Zn, based on the total weight of the catalyst.

[0099] Example 23 is the method of any of Examples 1-20, further comprising the additional step of catalytically reacting the composition to form HFC-245fa using a chromium catalyst having chromium (VI) oxide in an amount less than 1,000 ppm, less than 500 ppm, less than 150 ppm, or less than 100 ppm.

[0100] While the present disclosure has been described in terms of exemplary designs, the present disclosure may be further modified within the spirit and scope of the present disclosure, and this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which the disclosure pertains.

Claims

1. 1. A composition useful as a feedstock for the production of HFC-245fa, comprising: at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), wherein the total amount of said compound is 50 wt% or more, based on the total weight of said composition; at least one very high boiling component, all of which are present in a combined amount of 1 wt.% or less based on the total weight of the composition; A composition comprising:

2. 10. The composition of claim 1, wherein the at least one very high boiling component comprises a mixture of fluorinated components having a boiling point greater than about 140.2°C.

3. 10. The composition of claim 1, wherein the at least one very high boiling point component comprises at least one of hexachloroethane and halogenated hydrocarbons having 5 or more carbon atoms.

4. 10. The composition of claim 1, wherein the at least one very high boiling point component is present in a total amount of less than or equal to 0.5 weight percent, based on the total weight of the composition.

5. 2. The composition of claim 1, wherein the at least one very high boiling point component comprises hexachloroethane in an amount less than 0.3 weight percent, based on the total weight of the composition.

6. 2. The composition of claim 1, wherein the at least one very high boiling point component comprises hexachloroethane in an amount less than 0.1 weight percent, based on the total weight of the composition.

7. 2. The composition of claim 1, wherein the combined amount of the at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244) is 85 wt% or more, based on the total weight of the composition.

8. 2. The composition of claim 1, wherein the combined amount of the at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244) is 95 wt% or greater, based on the total weight of the composition.

9. 1. A process for producing a composition useful as a feedstock for the production of HFC-245fa, comprising the steps of: at least partially condensing a composition comprising at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), and at least one very high boiling component; a vaporized stream comprising at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244); and a liquid stream comprising said at least one very high boiling point component; forming a separating the vaporized stream from the liquid stream; Optionally, feeding said vaporized stream to an HFC-245 reactor; A method comprising:

10. The vaporized stream is at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), wherein the total amount of said compound is 50 wt% or more, based on the total weight of said composition; at least one very high boiling component, all of which are present in a combined amount of 1 wt.% or less based on the total weight of the composition; 10. The method of claim 9, comprising:

11. 10. The method of claim 9, wherein the at least one very high boiling point component is present in a combined amount of less than or equal to 0.5 wt.%, based on the total weight of the vaporized stream.

12. 10. The method of claim 9, wherein the at least one very high boiling component comprises hexachloroethane in an amount less than 0.3 weight percent based on the total weight of the vaporized stream.

13. 10. The method of claim 9, wherein the at least one very high boiling component comprises hexachloroethane in an amount less than 0.1 weight percent based on the total weight of the vaporized stream.

14. 10. The method of claim 9, wherein the at least one very high boiling component comprises a mixture of fluorinated components having a boiling point greater than about 140.2°C.

15. 1. A process for producing a composition useful as a feedstock for the production of HFC-245fa, comprising the steps of: distilling a composition comprising at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), and very high boiling components to produce a distillate stream and a very high boiling component stream; Optionally, feeding said distillate stream to an HFC-245 reactor; A method comprising:

16. the distillate stream at least one compound selected from the group consisting of isomers of 1,1,3,3-tetrachloro-1-fluoropropane (HCFC-241fa), isomers of 1,3,3-trichloro-1,1-difluoropropane (HCFC-242), isomers of 3,3-dichloro-1,1,1-trifluoropropane (HCFC-243), and isomers of 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244), wherein the total amount of said compound is 50 wt% or more, based on the total weight of said composition; at least one very high boiling component, wherein all very high boiling components are present in a combined amount of 1 wt.% or less based on the total weight of said distillate stream; 16. The method of claim 15, comprising:

17. 16. The method of claim 15, wherein the at least one very high boiling point component comprises a mixture of fluorinated components having a boiling point greater than about 140.2°C.

18. 16. The method of claim 15, wherein said at least one very high boiling component is present in a combined amount of less than or equal to 0.5 weight percent, based on the total weight of said distillate stream.

19. 16. The method of claim 15, wherein said at least one very high boiling component comprises hexachloroethane in an amount less than 0.3 weight percent based on the total weight of said distillate stream.

20. 16. The method of claim 15, wherein said at least one very high boiling component comprises hexachloroethane in an amount less than 0.1 weight percent based on the total weight of said distillate stream.

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