SYSTEMS AND METHODS FOR REDUCING FORMATION OF IMPURITIES DURING 244bb DEHYDROCHLORINATION TO 1234yf

Abstract

To provide a method for producing HFO-1234yf which may allow for the improved yields, more economical processes, and waste reduction in the production of 1234yf and subsequent processes.SOLUTION: There is provided a method of manufacturing 2,3,3,3-tetrafluoropropene (HFO-1234yf) comprising: providing a feed comprising 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) and at least one impurity; removing the at least one impurity from the feed until the feed contains less than 200 ppm of the at least one impurity; and dehydrochlorinating the HCFC-244bb in the feed to form a product stream containing HFO-1234yf, wherein the at least one impurity comprises 1-chloro-3,3,3-trifluoropropane (HCFC-253fb), 1,1,1,3,3-pentafluoropropane (HFC-245fa) and the like.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] This disclosure relates to a manufacturing method for reducing the formation of impurities during the production of HFO-1234yf. and relating to the system. More specifically, this disclosure relates to 2-chloro-1,1,1,2-teto Impurities during the dehydrochlorination of lafluoropropane (HCFC-244bb or 244bb) Reduces the formation of 2,3,3,3-tetrafluoropropene (HFO-1234yf or This concerns a method for forming 1234yf. [Background technology]

[0002] Hydrofluoroolefins (HFOs), such as tetrafluoropropene, are known to have Effective refrigerants, fire extinguishing agents, heat transfer fluids, propellants, foaming agents, blowing agents, gaseous dielectrics, sterilizing agent carriers, polymerization The medium, particulate removal fluid, liquid carrier, buffing abrasive, displacement drying agent, and power circulating working fluid are The use of some of these fluids, including those with relatively high global warming potentials, is related to them. Due to suspected related environmental problems, it also has a zero ozone depletion potential (ODP). In addition, it is desirable to use a fluid with the lowest possible global warming potential (GWP). Therefore, there is considerable interest in developing environmentally friendly materials for the aforementioned applications. ru.

[0003] Hydrofluoroolefins (H) have zero ozone depletion and a low global warming potential. FO) has been identified as potentially fulfilling this need. However, The toxicity, boiling point, and other physical properties of such chemicals change significantly from isomer to isomer. One HFO with useful properties is 2,3,3,3-tetrafluoropropene ( It is HFO-1234yf or 1234yf).

[0004] HFO-1234yf has been shown to be a low-toxicity, low-global-warming compound. Therefore, it is possible to increasingly meet the stringent requirements for refrigerants in mobile air conditioning. Therefore, compositions containing HFO-1234yf are used in many of the aforementioned applications. It exists among the materials being developed for that purpose.

[0005] U.S. Patent No. 8,058,486, Title of Invention: "INTEGRATED PROCE SS TO PRODUCE 2,3,3,3-TETRAFLUOROPOPENE (Published November 15, 2011), U.S. Patent No. 8,975,454, Title of Invention "P ROCESS FOR PRODUCING 2,3,3,3-TETRAFLUORO PROPENE (issued March 10, 2015), U.S. Patent No. 8,766,020, The name of the invention is "PROCESS FOR PRODUCING 2,3,3,3-TETR As described in "AFLUOROPROPENE" (published July 1, 2014), Various methods for generating HFO-1234yf are known, and the whole is described in the references. This specification is incorporated herein. [Overview of the project]

[0006] This disclosure relates to 2,3,3,3-tetrafluoropropene (HFO-1234yf or 1 This provides various manufacturing processes for the production of 234yf). Improvement of yield in the production of 234yf and subsequent processes, a more economical process, and This could enable a reduction in waste.

[0007] According to various aspects of this disclosure, 2,3,3,3-tetrafluoropropene (HFO- The method for producing 1234yf) is 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) and at least one heavy element having a boiling point higher than approximately 15°C To provide a feed containing machine impurities, and a feed containing at least one impurity of 200 Remove at least one impurity from the feed until it is contained in less than ppm, and in the feed HCFC-244bb is dehydrochlorinated to produce a product containing HFO-1234yf. This may include forming a feed product containing at least one impurity. It is preferable to remove at least one impurity from the supply until it contains less than 100 ppm of [unspecified impurity]. Furthermore, until the supply contains at least one impurity at a concentration of less than 50 ppm, It is preferable to remove at least one impurity.

[0008] In some embodiments, at least one impurity is 1,1,1,3-tetrachloro Lopropane (HCFC-253fb), 1,1,1,3,3-pentafluoropropane ( HFC-245fa), chlorohexafluorobutene (HFO-1326 isomer), hex Safluorobutene (HFO-1336 isomer), pentafluorobutene (HFO-134 (5 isomers), heptafluorobutene (HFO-1327 isomer), 2,3-dichloro-1 ,1,1,2-tetrafluoropropane (HFC-234bb), chlorotetrafluoro Propene (HCFO-1224 isomer), tetrafluorohexane (HFC-5-11- 4 isomers), tetrafluoropropane (HFC-254 isomer), chlorohexafluoro Butane (HFC-346 isomer), octafluoropentane (HFC-458 isomer), Chlorotrifluoropropene (HCFO-1233 isomers), (E)-1-chloro-3, 3,3-trifluoropropene (HCFO-1233zd(E)), 2-chloro-1,1 ,1,3,3-pentafluoropropane (HCFC-235da), octafluorohex ene, 3-chloro-1,1,1,2-tetrafluoropropane (HFC-244eb), 2,2-dichloro-1,1,1-trifluoroethane (HCFC-123), (Z)-1 -chloro-3,3,3-trifluoropropene (HCFO-1233zd(Z)), C5 H2F 10 isomers, C6H2F8 isomers, C6H4F8 isomers, decafluorobutane (C 4F 10 ), C6H3F7 isomers, C6H3F9 isomers, dichlorodifluoropropene (HCFO-1232 isomers), dichlorotrifluoropropene (HCFO-1223 isomers ), dichlorotetrafluoropropane (HCFC-234 isomers), dichlorotriflu oropropane (HCFC-243 isomers), trichlorotrifluoropropane (HCFC -233 isomers), C6H3Cl2F7 isomers, trichlorodifluoropropane (HCF C-242 isomers), C8H3F7 isomers, tar, or at least one of a combination thereof.

[0009] The various methods may further include treating the product stream containing HFO-1234yf with at least one of a column containing HCl, a column containing water, a column containing a caustic solution, a scrubber, a dryer, a distillation column, or a combination thereof.

[0010] To produce 2,3,3,3-tetrafluoropropene (HFO-1234yf), several Another method is 2-chloro-1,1,1,2-tetrafluoropropane (HCFC- 244bb) and to provide a supply containing at least one impurity, and HCFC-2 44bb is dehydrochlorinated in the feed to form a product stream containing HFO-1234yf. To achieve the formation of 1140, 1243zf or a combination thereof below a predetermined threshold This may include controlling the feed. In various embodiments, this may involve HCFC- Before dehydrochlorinating 244bb, 1,1,1,3-tetrachloropropane (HCFC) This may include removing -253fb). [Brief explanation of the drawing]

[0011] Refer to the following description of exemplary embodiments of this disclosure in conjunction with the attached drawings. Therefore, the above-mentioned and other features and objectives of this disclosure, as well as the methods for achieving them, will become clearer. This will lead to a better understanding of the disclosure itself.

[0012] [Figure 1A] This is a process flow diagram illustrating an exemplary portion of the manufacturing process for 2,3,3,3-tetrafluoropropene (HFO-1234yf).

[0013] [Figure 1B] This process flow diagram is similar to the process flow shown in Figure 1A, but with the addition of a third distillation column in series.

[0014] [Figure 1C] This process flow diagram is similar to the process flow shown in Figure 1A, illustrating an exemplary portion of the manufacturing process of 2,3,3,3-tetrafluoropropene (HFO-1234yf) using side draws from a distillation column.

[0015] [Figure 2]This is a process flow diagram showing step 3 of an exemplary process for manufacturing HFO-1234yf.

[0016] [Figure 3] Some examples of methods for manufacturing HFO-1234yf while controlling the formation of 1140, 1243zf and combinations thereof by various embodiments are illustrated.

[0017] [Figure 4] Various embodiments of methods for manufacturing HFO-1234yf are illustrated.

[0018] [Figure 5] This chart illustrates 244bb conversion data using two different 244bb supply materials.

[0019] Corresponding reference letters indicate the corresponding parts across several figures. The drawings are provided in this disclosure. The drawings illustrate embodiments, but are not necessarily to scale. This disclosure is intended to better illustrate and illustrate the present disclosure. Certain features may be exaggerated for illustrative purposes. The examples provided herein are This document illustrates exemplary embodiments of the present disclosure in various forms, and such examples are not limited to any particular context. Even in this format, it should not be interpreted as limiting the scope of this disclosure. [Modes for carrying out the invention]

[0020] As briefly stated above, this disclosure relates to 2,3,3,3-tetrafluoropropene (HF This provides various methods and systems for the manufacture of O-1234yf or 1234yf). HFO-123 from 1,1,2,3-tetrachloropropene (TCP) and hydrogen fluoride The manufacturing of 4yf can be generalized into three process steps.

[0021] 2-Chloro-1,1,1,2-tetrafluoropropane Step 1 is carried out in a vapor phase reactor according to the following reaction scheme: 1,1,2,3-T Trachloropropene (1230xa) to 2-chloro-3,3,3-trifluoropropene This can be understood as generating (HCFO-1233xf). [ka]

[0022] Step 2 is carried out according to the following reaction scheme: 2-chloro-3,3,3-trifluoroprop From PEN (HCFO-1233xf) to 2-chloro-1,1,1,2-tetrafluoropro This can be understood as producing bread (HCFC-244bb). [ka]

[0023] Step 3 is carried out in a reactor such as a vapor phase reactor, according to the following reaction scheme, 2- From 1,1,1,2-tetrafluoropropane (HCFC-244bb) to 2,3, This is understood as the production of 3,3-tetrafluoropropene (HFO-1234yf). It is possible. [ka]

[0024] While we do not wish to be bound by any particular operating theory, the present invention has a specific The embodiment is 2,3,3,3-tetrafluoropropene (HFO-123) produced by step 3 above. 2-chloro-1,1,1,2-tetrafluoropropane (HCl) to produce 4yf During specific dehydrochlorination reactions of certain dehydrochlorination initiating materials such as FC-244bb), Based on the observation and understanding that the presence of certain impurities has been found to be harmful and unfavorable. It is.

[0025] For example, 3-chloro-1,1,1-trifluoropropane (HCl) in the reactor of step 3 The presence of FC-253fb or 253fb) indicates 3,3,3-trifluoropropene (HF Elevated levels of both O-1243zf or 1243zf) and vinyl chloride (1140) This may result in the formation and / or presence of , which is subsequently found in the crude product 1234yf. The presence of 1243zf and 1140 impurities can result in extra yield loss during the final purification process. Because this can result in the difficulty of separating 1243zf and 1140 from 1234yf. For certain reasons, this is undesirable.

[0026] Furthermore, high boiler and tar (long chain halogens) formed as a side reaction in the reactor of step 3. The presence of (a nitrate hydrocarbon) may cause excessive coking of the reactor in step 3, or This is thought to be one of the contributing factors, leading to the premature deactivation of the reactor. A non-specific example of a high boiler is the C4F 10 , C5H2F 10 Isomers, various tetraphs Luorohexane isomer, C6H3F7 isomer, C6H3Cl2F7 isomer, C6H2F8 Isomers, C6H4F8 isomers, C6H3F9 isomers, various octafluorohexene isomers Examples include, but are not limited to, the C8H3F7 isomer. These high boilers It may react further to form tar, which condenses and, upon cooling, turns into a dark brown or black, viscous substance. It can form a liquid.

[0027] Therefore, for feeding to the reactor in step 3, reduction of specific impurities, and / or The reduction and separation of tar, high boiler material, and precursors of these materials is a more economical process. This enables improved uptime, higher yields, and improved use of metal surfaces in the reactor. This can be done. Next, it is also possible that the process be executed under mild conditions. This can be done, and it can also help prevent the formation of undesirable by-products.

[0028] The embodiments disclosed below are exhaustive, or may not be disclosed in the detailed description below. This disclosure is not intended to limit the present invention to any specific form. Rather, the embodiments are described below. The instructions are selected and explained so that the contractors can utilize them.

[0029] When used herein, the modifier "about" as used in relation to quantity is described as It includes a value and has a meaning determined by the context (for example, it is a measurement of a particular quantity). (including at least the degree of the associated error). When used in a range of contexts, it is equivalent to "approximately". The modifier can also be considered to disclose a range defined by the absolute values ​​of the two endpoints. For example, the range "approximately 2 to approximately 4" also discloses the range "2 to 4".

[0030] Figure 1A illustrates an exemplary manufacturing process flow 1 in various embodiments. This is a flow chart. HF supply 5 and 1233xf supply 3 (from process 1) are, for example, arbitrary. It may be combined with a pipe or container, for example, a combination flow valve 28, and heat It may be heated by the exchanger 24 and then supplied to the reactor 2 as flow 7. Figure 1A It can be shown as a liquid-phase reactor, and in reactor 2 shown in this way, HCFC-24 4bb is produced as briefly described above as step 2. The reaction of step 2 is carried out in the reactor. After step 2, the crude HCFC-244bb product stream 9 is sent to the catalyst stripper column 4. Here, the catalyst is separated and returned to reactor 2 in the return flow 18. Catalyst stripper column After processing in 4 and heat exchanger 22, the removed HCFC-244bb crude product stream 11 It is then sent to the light distillation column 6. In the light distillation column, the light boiler has a light column top flow 13 and The mixture is then distilled, while the light bottom flow 15 can be cooled by the heat exchanger 16, and the flow 24 It can be sent to the phase separator 8, where the light bottom flow 15 containing HCFC-244bb is separated. HF is separated from it. The HF phase then returns to the reactor in step 2 as a recirculated HF stream 19. It may be recycled, and the liquid stream 17 containing HCFC-244bb is one or more distillation cells. It may be sent to Lamb.

[0031] Figure 1A shows the initial distillation of distillation column 10, which is exemplified as an azeotropic distillation column in this embodiment. An example of the liquid flow 17 sent to the column is shown. In another embodiment, the distillation column 10 performs non-azeotropic distillation. It may be included.

[0032] In azeotropic distillation column 10, azeotropic distillation is used to extract HCFC-244bb from a liquid stream. FO-1233xf can be removed. When used in this specification, azeotropic distillation is used. The term includes distillation processes involving one or more azeotropes or azeotropic mixtures of two or more fluids. It is used in a broad sense. For this purpose, unreacted reagents and / or by-products from step 3 A third flow, such as the product, may be provided by a recirculating flow 29, which may be an azeotropic mixture or azeotropic composition. It forms a third component (for example) The presence of HF is a ternary relationship with HCFO-1233xf and / or HCFC-244bb. Azeotropic mixtures and / or binary azeotropic mixtures may be formed. Significant portion of HCFC-244bb Various azeotropic mixtures remain in the solution at the bottom 21, and distillation in the azeotropic distillation column 10 It can be separated from the solution using any standard separation method.

[0033] In various embodiments of this disclosure, to form an azeotropic or azeotropic mixture-like composition A composition is provided that contains an effective amount of HF, a light organic, a heavy organic, or a combination thereof. The term "effective amount" as used herein is used in combination with other components. When combined, this refers to the amount of each component that results in the formation of an azeotropic mixture or an azeotropic mixture-like mixture. As used herein, the terms "heterophase azeotropic mixture" and "heterogeneous azeotropic mixture" are used in this specification. The term includes azeotropic mixture-like compositions containing a vapor phase that exists simultaneously with two liquid phases.

[0034] Such azeotropic mixtures and methods for azeotropic separation or distillation are permitted under U.S. Law No. 7,803,28 U.S. Patent Application Publication No. 3 and U.S. Publication Nos. 2010 / 0187088 and 2009 / 0256110 This may further include what is disclosed in issue number, and all of the contents of each of these may be referenced. This specification is incorporated herein.

[0035] Next, the bottom 21 of the azeotropic column is a heavy distillation column that does not necessarily have to contain 253FB. As purified HCFC-244bb within ram12, and purified HCFC-244 It can be isolated as another heavy impurity, indicated as BB top flow 27, which can be further processed. It may be sent to a process (e.g., process 3) and / or stored in tank 60. Then, The top flow 23 from the ram can be returned and recirculated for reuse in step 2 within reactor 2. For example, using a combination flow valve 28, the supply flow 7 and a pipe or container are used. They can be combined.

[0036] Finally, it may contain enriched 253fb and tar and / or other heavy boilers. The bottom 25 of the heavy distillation column 12 is then collected and used to improve yield and / or discard. It may be used for additional recovery. When used herein, the term “heavy boiler” is used in this specification. It includes an organic composition having a boiling point higher than 244bb, which has a normal boiling point of approximately 14-15°C. It is possible. For example, in some embodiments, heavy organic compounds have a boiling point above about 15°C. Obtained. Heavy organic compounds include HCFC-253fb and C4F. 10 , C5H2F 10 isomer , various tetrafluorohexane isomers, C6H3F7 isomers, C6H3Cl2F7 isomers C6H2F8 isomer, C6H4F8 isomer, C6H3F9 isomer, various octaful Examples include orohexene isomers, C8H3F7 isomers, tar, or combinations thereof. It is possible.

[0037] Therefore, several embodiments such as the process flow diagrams shown in Figures 1A and 1B The removed impurities are 1-chloro-3,3,3-trifluoropropane (HCFC) -253fb), 1,1,1,3,3-pentafluoropropane (HFC-245fa) , chlorohexafluorobutene (HFO-1326 isomer), hexafluorobutene (H FO-1336 isomer), pentafluorobutene (HFO-1345 isomer), heptaf Luolobutene (HFO-1327 isomer), 2,3-dichloro-1,1,1,2-tetra Fluoropropane (HFC-234bb), chlorotetrafluoropropene (HCFO- 1224 isomer), tetrafluorohexane (HFC-5-11-4 isomer), tetraf Luolopropane (HFC-254 isomer), chlorohexafluorobutane (HFC-34 6 isomers), octafluoropentane (HFC-458 isomer), chlorotrifluoro Lopen (HCFO-1233 isomer), (E)-1-chloro-3,3,3-trifluoro Propen(HCFO-1233zd(E)), 2-chloro-1,1,1,3,3-penta Fluoropropane (HCFC-235da), octafluorohexene, 3-chloro-1 ,1,1,2-tetrafluoropropane (HFC-244eb), 2,2-dichloro-1 ,1,1-trifluoroethane (HCFC-123), (Z)-1-chloro-3,3,3 - Trifluoropropene (HCFO-1233zd(Z)), C5H2F 10 isomer, C 6H2F8 isomer, C6H4F8 isomer, decafluorobutane (C4F 10 ), C6H3 F7 isomer, C6H3F9 isomer, dichlorodifluoropropene (HCFO-1232 isomer) (isomer), dichlorotrifluoropropene (HCFO-1223 isomer), dichlorotetra Fluoropropane (HCFC-234 isomer), dichlorotrifluoropropane (HCFC) C-243 isomer), trichlorotrifluoropropane (HCFC-233 isomer), C 6H3Cl2F7 isomer, trichlorodifluoropropane (HCFC-242 isomer), It may contain at least one of the C8H3F7 isomer, tar, or a combination thereof. ru.

[0038] The process shown in Figure 1B includes many embodiments that are similar to or identical to those in Figure 1A. In some embodiments, such as the Lowe 30, the bottom 25 of the heavy distillation column 12 is the distillation column Further separation may be performed using a heavy recovery distillation column 32, etc. In some embodiments, heavy recovery distillation column 32 The high boiler and tar are further separated from the heavy distillation column 12 into the top section 33 and bottom section 35. This may also be the case. In various embodiments, the heavy recovery distillation column 32 operates by batch distillation. In other embodiments, the distillation column 32 may be operated by continuous distillation. In some embodiments, the purified product 244bb or the partially purified product 244bb is stored in a storage container. It may be stored in a storage container such as 60.

[0039] The process flow shown in Figure 1C includes many embodiments that are similar to or identical to those in Figure 1A. In some embodiments, such as 40, a side draw 47 from the distillation column 10 is used. The separation of the purified product 244bb is illustrated. In some embodiments, the use of side draw is demonstrated. Due to the high boiler and the vapor pressure difference between the tar and the refined product 244bb, the distillation column 10 This may be beneficial due to differences in separation within various trays.

[0040] Figure 2 shows 12 from a feed containing purified product 244bb and at least one impurity. A process flow diagram 70 illustrating the generation of 34yf is shown. The process flow diagram 70 in Figure 2 is As illustrated in the descriptions of Figures 1A and 1B, at least one of the aforementioned impurities The input flow 27 may contain HCFC-244bb.

[0041] Next, it contains HCFC-244bb and at least one of the aforementioned impurities. The composition is heated by the heat exchanger 24 and sent to the dehydrochlorination reactor 72 to produce 1234yf. It may be generated (step 3, which is briefly described above). Next, the reaction product containing 1234yf The product flow 75 can be sent to the recirculation column 62, where the bottom 63 returns to the reactor 72. And / or return to the azeotropic distillation column 10 of step 2 as flow 29 in Figures 1A and 1B. It can be recycled, and the top of the column 65 is purified by the HCl stream 67 in the HCl column 64. It may be sent to the scrubber. Then, the HCl purification stream 69 is purified with the solution stream 77 in the scrubber 74. This may be done. The solution stream 77 is not particularly limited and may be water, or, for example, a caustic solution or an acidic solution. The solution may be a solution such as a solution containing sulfuric acid. Then, the purified raw The production process 79 is concentrated sulfuric acid, a solid desiccant, or a mixture of solid desiccants, or concentrated sulfuric acid. A combination of this and a desiccant(s)(s) is sent to an acid-containing dryer 76, and any remaining residue can be removed. Any scrubbing solution / moisture may be removed. The pre-cooling step involves removing the desiccant in the dryer 76. To conserve energy, the scrubber 74 and the dryer 76 are used to differentially condense the water vapor. It can be incorporated in between.

[0042] Next, the dried product stream 81 can be distilled in the light distillation column 78, where light The top flow 83 of the solid tower passes through the heat exchanger 22 and is reused or removed. The bottom flow 85 of the light solid tower is heated It may be heated or cooled via the exchanger 26, and further distilled in the product distillation column 80. This is also fine. The purified 1234yf flow 87 may be processed through the heat exchanger 22, It may be stored in the container 82 and / or recycled. The bottom product flow 29 is heated It may be heated in the exchanger 26, or returned to the product distillation column 80 and recirculated, and They may be removed for disposal.

[0043] In some embodiments, the formation of 1140, 1243zf, or a combination thereof. For example, the effluent from the reactor in step 3 (shown as dehydrochlorination reactor 72 in Figure 2). Within this, it may be controlled to be below a predetermined threshold. In various embodiments, 1140, 1243z The formation of f, and combinations thereof, leads to the selective removal of their precursors such as 253fb. Therefore, it may be controlled.

[0044] While not limited to any particular theory, an increase in the amount of 253fb, This includes an increase in the amounts of other side reaction substances, such as 1243zf, 1140, and combinations thereof. It is thought that this may occur. With an increase in the level of 253fb, the following reaction scheme I and Desirable factors that may negatively affect yield, such as the formation of 1140 and 1243zf by II. It was found that this could lead to an increase in side effects. [ka]

[0045] Therefore, in various embodiments, 1243zf, 1140 and combinations thereof are used. The amount may be controlled to be below a predetermined threshold. For example, the aforementioned separation process such as distillation. Limiting the amount of HCFC-253fb using any of the processes is possible. This may help in controlling the amounts of O-1243zf and 1140. For example, several implementations Morphologically, HCFC-253fb is obtained by distillation or a series of processes, as shown in Figures 1A and 1B. It may be removed by distillation.

[0046] For example, in some embodiments, the amount of HCFC-253fb is approximately 200 ppm. Full level, level below approximately 100 ppm, level below approximately 50 ppm, or approximately 30 ppm It may be reduced to a level of less than m. This then applies to HFO-1243zf and 1140. This may help limit the formation of these (as shown in schemes I and II). This is due to the fact that precursors for the aforementioned compounds are not available.

[0047] For example, in some embodiments, by limiting the presence of HCFC-253fb The formation of 1140 is less than approximately 200 ppm, less than approximately 100 ppm, less than approximately 50 ppm, and The amount may be controlled to less than approximately 30 ppm.

[0048] Similarly, in some embodiments, the formation of 1243zf is also HCFC-253f It may be controlled by restricting the presence of b. Therefore, HFO-1243zf Formation occurs at concentrations of less than approximately 200 ppm, less than approximately 100 ppm, less than approximately 80 ppm, or less than approximately 50 ppm. It was controlled (minimized) to a level below pm.

[0049] In addition, in some embodiments, the combination of 1140 and 1243zf is approximately 30 The amount can be controlled to less than 0 ppm, less than approximately 200 ppm, less than approximately 100 ppm, or less than 80 ppm. It may be controlled. For example, in various embodiments, the formation of 1140 and 1243zf can be controlled. This involves removing 253fb before performing step 3, for example, step 3 This can be achieved by removing 253fb from the supply flow to the supply, and therefore, The flow rate is less than approximately 200 ppm, less than approximately 100 ppm, less than approximately 50 ppm, or less than 30 ppm. It has a quantity of 253 fb.

[0050] Therefore, the method for producing 2,3,3,3-tetrafluoropropene is shown in Figure 3 and This may include the method shown in 4. Figure 3 shows the production of 2,3,3,3-tetrafluoropropene. Method 101 is shown, which involves a supply containing 244bb and at least one impurity. Providing the material (step 110) and ensuring that the supplied material is below a predetermined threshold (e.g., about 200 pp) (less than m, less than approximately 100 ppm, less than approximately 50 ppm, and less than approximately 30 ppm) Remove at least one impurity from the feed until it contains one impurity (Step 1) 20) Dehydrochlorination of 244bb in the feed to produce a product stream containing 1234yf This may include forming (step 130).

[0051] Figure 4 shows the production of 2,3,3,3-tetrafluoropropene according to various embodiments. Let us illustrate another method. Method 301 may include steps 110 and 130 described above. Method 301 also forms 1243zf, 1140, or a combination thereof at a predetermined threshold The process may include a step (step 140) to control the value to less than the specified value. In various embodiments, this may be 2 This can be achieved by removing 53fb to a predetermined threshold.

[0052] Dehydrochlorination of HCFC-244bb is performed at 200°C to 800°C, preferably 300°C. A temperature range of ~600°C, more preferably 425°C to 525°C, and 0 to 300 psig. Preferably carried out in a pressure range of 5 to 200 psig, more preferably 20 to 100 psig. It is possible. The residence time of HCFC-244bb in the reactor is in the range of approximately 1 second to approximately 320 seconds. It is acceptable, but a longer or shorter duration can be used.

[0053] As mentioned above and shown in various process flow diagrams, the removal of at least one impurity is This may include the use of one or more different separation or manufacturing processes. (Example process) The processes include decanting, centrifugal separation, liquid extraction, distillation, flash distillation, partial vaporization, and partial condensation. This could be a reduction, or a combination thereof. The isolation process can be a continuous or batch process. This may be carried out, for example, in a multi-stage distillation column that can be operated in batch mode or continuous mode. In some embodiments, separation of impurities is achieved by side drawing from a distillation column. It is possible.

[0054] In some embodiments, the product stream containing 1234yf may be further processed. i. For example, in some embodiments, several separated flows or further processed flows This may be recycled to improve the overall yield of the process. For example, several In this embodiment, unreacted 2-chloro-1,1,1,2-tetrafluoropropane is re- The dehydrochlorination process may be reused after the dehydrochlorination by using a circulating column.

[0055] Further processing is not particularly limited and may include HCl recovery columns, caustic scrubbers, sulfuric acid drying columns, This may include various procedures having multiple unit operations, such as product purification columns. [Examples]

[0056] Example 1 The purpose of the following examples is to remove 253fb and other high boilers from the 244bb crude product. The goal was to demonstrate the feasibility of performing batch distillation with a 1:1 RR (magnetic flux ratio). This was done using 15 tray glass Oldershaw batch columns. Approximately 3. Eight pounds of 244bb crude was packed into a glass still. During distillation, four distillates were cut. After the distillation, a mostly black residue remained in the reboiler. As shown in Table 1, initially Compared to the 244bb crude product, 253fb and other heavy components were significantly lower in the distillate. While reduced, it was enriched in the reboiler (25% in the initial 244 bb crude, 145 ppm). Compared to 3fb, cuts 1-3 contain 253fb with less than 5ppm, and cut 4 contains 89 It contains 0.0 ppm of 253 fb, while the reboiler residue contains 9551 ppm of 253 fb. It contained approximately 1.25% of other heavy components, while cuts 1-3 contained less than 0.65% of other components. It contains heavy components, with cut 4 containing approximately 1.23% of other heavy components, while the reboiler residue... (It had 21.66% other heavy components). These results indicate that 253fb and other heavy components This demonstrates that the substance could be effectively reduced by distillation. [Table 1]

[0057] In Table 1 above, "Other lighter" is lower than 244bb, which does not include 1233xf. This refers to components that have a high boiling point (for example, a non-limiting example is tetrafluoropropene). HFO-1234 isomer, pentafluoropropene (HFO-1225 isomer), heptagon Fluorobutene and 2-chloro-1,1,1,2-tetrafluoroethane (HCFC- 124) is one example.

[0058] In Table 1 above, "other heavy minerals" have boiling points higher than 244 bb, except for 253 fb. This refers to a component that has (a non-limiting example is 1,1,1,3,3-pentafluoropro Pancake (HFC-245fa), chlorohexafluorobutene (HFO-1326 isomer) , hexafluorobutene (HFO-1336 isomer), pentafluorobutene (HFO- 1345 isomer), heptafluorobutene (HFO-1327 isomer), 2,3-dichloro 1,1,1,2-tetrafluoropropane (HFC-234bb), chlorotetrafluoro ropene (HCFO-1224 isomer), tetrafluorohexane (HFC-5- 11-4 isomer), tetrafluoropropane (HFC-254 isomer), chlorohexafluoro robutane (HFC-346 isomer), octafluoropentane (HFC-458 isomer ), chlorotrifluoropropene (HCFO-1233 isomer), (E)-1-chloro -3,3,3-trifluoropropene (HCFO-1233zd(E)), 2-chloro- 1,1,1,3,3-pentafluoropropane (HCFC-235da), octafluoro hexene, 3-chloro-1,1,1,2-tetrafluoropropane (HFC-244e b), 2,2-dichloro-1,1,1-trifluoroethane (HCFC-123), (Z )-1-chloro-3,3,3-trifluoropropene (HCFO-1233zd(Z)) , C5H2F 10 isomer, C6H2F8 isomer, C6H4F8 isomer, decafluorobutane (C4F 10 ), C6H3F7 isomer, C6H3F9 isomer, dichlorodifluoroprop ene (HCFO-1232 isomer), dichlorotrifluoropropene (HCFO-122 3 isomer), dichlorotetrafluoropropane (HCFC-234 isomer), dichlorot rifluoropropane (HCFC-243 isomer), trichlorotrifluoropropane (H CFC-233 isomer), C6H3Cl2F7 isomer, trichlorodifluoropropane ( Examples include the HCFC-242 isomer, the C8H3F7 isomer, and tar. Example 2

[0059] The objective of the following examples is to make it feasible to remove high boiler from 244bb crude product. The objective was to demonstrate the properties. Batch distillation was performed using a 10-gallon jacketed reboiler, Mo 2-inch inner diameter x 8 packed with nel Pro-Pak® column packing The distillation was carried out in a column with a height of ft, and in a distillation column consisting of a shell and tube condenser. The ram had approximately 35-40 theoretical stages. The distillation column was controlled by temperature, pressure, and differential pressure transmitters. The equipment was prepared. The distillate velocity was measured using a Coriolis flow meter.

[0060] Approximately 98 pounds of 244 bb crude was packed into an S1 distillation column. Its composition is shown in Table 2. Next, distillation was started and carried out at a pressure of approximately 12-15 psig. 92 pounds of purified liquid were then obtained. The 244bb distillate was recovered. The 244bb distillate was analyzed. Its composition is shown in Table 2. As shown in Table 2, 253fb was completely removed after distillation, but the total amount of other heavy components was significantly reduced. It decreased significantly.

[0061] After distillation was complete, approximately 3 pounds of black reboiler residue was discharged from the reboiler. Subsequently, 92 pounds of refined 244 bb distillate, feed stock for dehydrochlorination reaction experiment and I used it. [Table 2]

[0062] In Table 2 above, "other light grades" refers to grades lower than 244bb, excluding 1233xf. This refers to components that have a boiling point (a non-limiting example is tetrafluoropropene (HFO-1)). 234 isomers, pentafluoropropene (HFO-1225 isomer), heptafluoro Tene and 2-chloro-1,1,1,2-tetrafluoroethane (HCFC-124) (They can be listed.)

[0063] In Table 2 above, "other heavy minerals" have boiling points higher than 244 bb, except for 253 fb. This refers to a component that has (a non-limiting example is 1,1,1,3,3-pentafluoropro Bread (HFC-245fa), chlorohexafluorobutene (HFO-1326 isomer) , hexafluorobutene (HFO-1336 isomer), pentafluorobutene (HFO- 1345 isomer), heptafluorobutene (HFO-1327 isomer), 2,3-dichloro Ro-1,1,1,2-tetrafluoropropane (HFC-234bb), chlorotetraf Luolopropene (HCFO-1224 isomer), tetrafluorohexane (HFC-5- 11-4 isomers), tetrafluoropropane (HFC-254 isomer), chlorohexaf Luolobutane (HFC-346 isomer), Octafluoropentane (HFC-458 isomer) (E)-1-chlorotrifluoropropene (HCFO-1233 isomer), (E)-1-chloro -3,3,3-trifluoropropene (HCFO-1233zd(E)), 2-chloro- 1,1,1,3,3-Pentafluoropropane (HCFC-235da), Octafluoro Lohexene, 3-chloro-1,1,1,2-tetrafluoropropane (HFC-244e b) 2,2-dichloro-1,1,1-trifluoroethane (HCFC-123), (Z )-1-chloro-3,3,3-trifluoropropene (HCFO-1233zd(Z)) , C5H2F 10 Isomers, C6H2F8 isomers, C6H4F8 isomers, decafluorobuta n(C4F 10 ), C6H3F7 isomer, C6H3F9 isomer, dichlorodifluoropropyl Pen (HCFO-1232 isomer), dichlorotrifluoropropene (HCFO-122 (3 isomers), dichlorotetrafluoropropane (HCFC-234 isomer), dichloroto Lifluoropropane (HCFC-243 isomer), trichlorotrifluoropropane (H CFC-233 isomer), C6H3Cl2F7 isomer, trichlorodifluoropropane ( Examples include the HCFC-242 isomer, the C8H3F7 isomer, and tar. Example 3

[0064] Two 11.5-inch Inconel® 625 tubes (3 / 4 inch The outer diameter (0.035 inch wall thickness) is used in step 3 of the reaction (dechlorination of HCFC-244bb). It is used as a reactor for the process of ionization to produce HFO-1234yf, and an electrical box is used. They were installed in parallel inside the bunker. After heating the tube reactor to a given temperature by N2 purging, Starting material containing HCFC-244bb and other impurities is supplied to each tube reactor, and each supply The feed was independently controlled by a mass flow meter and controller. The pressure of each reactor was controlled by the pressure The flow in both reactors was independently controlled by a pressure control system including a converter and control valve. The excrete is routed through a scrubber containing a 10% KOH solution, and the product generated during the process is The HCl was neutralized. The sample was removed from the sample port before the crude product reached the scrubber solution. Samples were collected periodically using a sample bag containing a fixed amount of deionized H2O.

[0065] In one reactor, the composition was the same as that of the 244bb crude in Example 2 (regarding that composition...) (See Table 2) Undistilled 244 bb crude was used as the starting material.

[0066] In other reactors, the distilled 244bb was the 244bb distillate from Example 2 ( (See Table 2 for the composition) was used as the starting material.

[0067] Both reactors were subjected to the same reaction conditions (480°C, 70 psig, and equivalent residence time of 80 seconds). It operates at a supply rate of 43 g / h, and 244 bb of converted data is shown in Figure 5.

[0068] The reactor using 244bb crude as the starting material showed a significant outlet rupture after 24 hours of operation. I experienced a rag gauge. Visual observation revealed that a tar-like black solid was packed into the reactor outlet. It was there. After removing the tar-like material, the outlet was plugged back in. The reaction was restarted after 8 hours. The device was opened. After removing the tar-like material, the third plug gauge was observed. A reaction occurred after 16 hours. We restarted the process. The conversion of 244bb was very low using 244bb coarse as the starting material. , it was unstable. On the other hand, the reactor was operated using distilled 244bb as the starting material. This allows for the maintenance of high and stable activity after the induction period without any operational problems. It worked. In addition, when using 244bb crude as the starting material, the normalized HFO in the reactor effluent The concentrations of -1243zf and 1140 were 159 ppm and 247 ppm, respectively. For 244 bb distilled as the starting material, the average normalized HFO-124 in the reactor effluent. The concentrations of 3zf and HCC-1140 were 75 ppm and 30 ppm, respectively. Example 4

[0069] 21.5 g of the distilled 244 bb described in Example 2 was heated at 465°C and 70 psig. Using a supply rate of / h (equivalent to a residence time of 164 seconds), the reactor described in Example 3 It was supplied to one of the reactor effluents. GC analysis revealed that the average normalized HFO-1243z in the reactor effluent was found. The concentrations of f and HCC-1140 were 56 ppm and 38 ppm, respectively. Example 5

[0070] The 244bb distilled as described in Example 2 was subjected to a 43g / h rate at 465°C and 70psig. Using the supply rate (equivalent to a residence time of 82 seconds), one of the reactors described in Example 3 It was supplied to the reactor effluent. GC analysis revealed that the average normalized HFO-1243zf and The HCC-1140 concentrations were 71 ppm and 27 ppm, respectively. Example 6

[0071] 21.5 g of the distilled 244bb described in Example 2 was prepared at 480°C and 70 psig. Using a supply rate of / h (equivalent to a residence time of 161 seconds), the reactor described in Example 3 It was supplied to one of the reactor effluents. GC analysis revealed that the average normalized HFO-1243z in the reactor effluent was found. The concentrations of f and HCC-1140 were 59 ppm and 98 ppm, respectively. Example 7

[0072] The 244bb distilled as described in Example 2 was subjected to 480°C and 58 psig for 43 Using a supply rate of g / h (equivalent to a residence time of 69 seconds), the explanation described above was given in Example 3. It was supplied to one of the reactors. GC analysis revealed that the mean-normalized HFO- in the reactor effluent was The concentrations of 1243zf and HCC-1140 were 68 ppm and 21 ppm, respectively. . Example 8

[0073] Under the same reaction conditions as described in Example 3, 27 ppm of HFC-253fb, 9 The starting material containing 8.46% 244bb and 0.84% ​​1233xf was added to the reactor. We supplied it to one of our plants. GC analysis revealed that the mean-normalized HFO-1243 in the reactor effluent... The concentrations of zf and HCC-1140 were 63 ppm and 42 ppm, respectively. Example 9

[0074] Under the same reaction conditions as described in Example 3, 41 ppm HFC-253fb, 9 The starting material containing 8.42% 244bb and 0.85% 1233xf was added to the reactor. We supplied it to one of our plants. GC analysis revealed that the mean-normalized HFO-1243 in the reactor effluent... The concentrations of zf and HCC-1140 were 78 ppm and 44 ppm, respectively. Example 10

[0075] Under the same reaction conditions as described in Example 3, 53 ppm HFC-253fb, 9 The starting material containing 7.32% 244bb and 1.47% 1233xf was added to the reactor. We supplied it to one of our plants. GC analysis revealed that the mean-normalized HFO-1243 in the reactor effluent... The concentrations of zf and HCC-1140 were 120 ppm and 165 ppm, respectively. Example 11

[0076] Under the same reaction conditions as described in Example 3, 14 ppm HFC-253fb, 9 It contains 8.59% 244bb and 1.03% 1233xf (heavy due to distillation) The starting material from the plant (after removal of certain components) was fed into one of the reactors. GC analysis revealed The average normalized concentrations of HFO-1243zf and HCC-1140 in the reactor effluent were The concentrations were 48 ppm and 23 ppm, respectively.

[0077] Although this disclosure has been described as having an exemplary design, this disclosure is intended to convey the intent and purpose of this disclosure. Further modifications may be made within the scope. Therefore, this application utilizes the general principle of this application. It is intended to encompass all variations, uses, or adaptations of the indicated. Furthermore, this application, Such disclosures relating to known or customary practices in the relevant art are considered to be from this disclosure. It is intended to include deviations.

[0078] Furthermore, the connecting lines shown in the various drawings included herein are exemplary mechanisms between various elements. It is intended to show functional relationships and / or physical connections. In actual systems, there are numerous alternatives. Alternatively, it should be noted that additional functional relationships or physical connections may exist. However, Benefits, advantages, solutions to problems, and the ability to produce any benefits, advantages, or solutions. Any element that may make it more prominent may be considered an important, necessary, or essential feature or element. It should not be interpreted in that way. Therefore, the scope is limited to the scope of the attached claims. Furthermore, references to singular elements mean "one and only one" unless explicitly stated otherwise. It is not intended to mean doing something, but rather to mean "one or more." The use of a phrase similar to "at least one of A, B, or C" in the claims In some embodiments, the phrase may consist of A alone, and in other embodiments, B alone. They may exist independently, and in some embodiments, C may exist alone, or elements A, B , or any combination of C, for example, A and B, A and C, B and C, or A and B and It is intended to be interpreted that this means that C may exist in one embodiment.

[0079] In the detailed description herein, the terms "one embodiment," "a certain embodiment," and "exemplary embodiment" are used. References to "implementation form," etc., are made even if the described embodiment includes specific features, structures, or characteristics. However, not all embodiments necessarily include their particular features, structure, or characteristics. This indicates that. Furthermore, such phrases do not necessarily refer to the same embodiment. Furthermore, When a particular feature, structure, or characteristic is described in relation to a particular embodiment, it is explicitly stated. Whether or not they are described in detail, such features, structures, etc. in relation to other embodiments Or, if it is found to be within the scope of knowledge of a person skilled in the art, along with the interest of this disclosure in affecting the characteristics, It is shown. After reading the description, those skilled in the art will understand the practical aspects of this disclosure in alternative embodiments. The method of implementation will become clear.

[0080] Furthermore, the elements, components, or steps of the methods in this disclosure are elements, components, or methods. Regardless of whether the legal process is explicitly enumerated in the claims, dedicated to the public It is intended that the claim elements of this specification use the phrase “means” Unless explicitly enumerated otherwise, it shall be interpreted under Section 112(f) of the U.S. Patent Act. It is not. When used in this specification, "comprises" and "comprising" are used. The term "g)" or any other variation thereof is intended to encompass non-exclusive inclusions. The diagram illustrates that a process, method, article, or apparatus containing a list of elements is therefore one of those. This does not include only the elements, but is explicitly listed in such processes, methods, articles, or apparatus. It may not include, or may include, other unique elements.

Claims

[Claim 1] A method for producing 2,3,3,3-tetrafluoropropene (HFO-1234yf), comprising: providing a feed comprising 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) and at least one impurity; removing said at least one impurity from said feed until said feed contains less than 200 ppm of said at least one impurity; dehydrochlorinating the HCFC-244bb in the feed to form a product stream containing HFO-1234yf; The at least one impurity is selected from the group consisting of 1-chloro-3,3,3-trifluoropropane (HCFC-253fb), 1,1,1,3,3-pentafluoropropane (HFC-245fa), chlorohexafluorobutene (HFO-1326 isomers), hexafluorobutene (HFO-1336 isomers), pentafluorobutene (HFO-1345 isomers), heptafluorobutene (HFO-1327 isomers), 2,3-dichloro-1,1,1,2-tetrafluoropropane (HFC-234bb), chlorotetrafluoropropene (HCFO-1224 isomers), tetrafluorohexane (HFC-5-11-4 isomers), tetrafluoropropane (HFC-2 54 isomer), chlorohexafluorobutane (HFC-346 isomer), octafluoropentane (HFC-458 isomer), chlorotrifluoropropene (HCFO-1233 isomer), (E)-1-chloro-3,3,3-trifluoropropene (HCFO-1233zd(E)), 2-chloro-1,1,1,3,3-pentafluoropropane (HCFC-235da), octafluorohexene, 3-chloro-1,1,1,2-tetrafluoropropane (HFC-244eb), 2,2-dichloro-1,1,1-trifluoroethane (HCFC-123), (Z)-1-chloro-3,3,3-trifluoropropene (HCFO-1233zd(Z)), C ５ H ２ F １０ isomer, C ６ H ２ F ８ isomer, C ６ H ４ F ８ isomer, decafluorobutane (C ４ F １０ ), C ６ H ３ F ７ isomer, C ６ H ３ F ９ Isomers, dichlorodifluoropropene (HCFO-1232 isomer), dichlorotrifluoropropene (HCFO-1223 isomer), dichlorotetrafluoropropane (HCFC-234 isomer), dichlorotrifluoropropane (HCFC-243 isomer), trichlorotrifluoropropane (HCFC-233 isomer), C ６ H ３ Cl ２ F ７ Isomers, Trichlorodifluoropropane (HCFC-242 Isomers), C ８ H ３ F ７ at least one of isomers, tars, or a combination thereof.

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