Method for producing trans-1,2-difluoroethylene (HFO-1132E)

Abstract

HFO-1132, particularly HFO-1132E, can be produced from 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113). In the first step, 1,1,2-trifluoroethane (HFC-143) is produced by hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) in the presence of a catalyst for producing 1,1,2-trifluoroethane (HFC-143). Then, 1,1,2-trifluoroethane (HFC-143) can be dehydrofluorinated in the presence of a catalyst to produce trans-1,2-difluoroethylene (HFO-1132E) and / or cis-1,2-difluoroethylene (HFO-1132Z). Next, cis-1,2-difluoroethylene (HFO-1132Z) can be isomerized to produce trans-1,2-difluoroethylene (HFO-1132E).

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims priority to U.S. Patent Application No. 18 / 658,300, filed on May 8, 2024, which claims the benefit of U.S. Provisional Patent Application No. 63 / 465,142, filed on May 9, 2023, and U.S. Provisional Patent Application No. 63 / 534,001, filed on August 22, 2023, under 35 U.S.C. § 119(e), and the disclosures of which are hereby incorporated by reference in their entireties.

[0002] (Field of the Invention) This disclosure is directed to a method for producing trans - 1,2 - difluoroethylene (HFO - 1132E) from 1,1,2 - trichloro - 1,2,2 - trifluoroethane (CFC - 113).

Background Art

[0003] 1,2 - Difluoroethylene (HFO - 1132) has been found to be increasingly useful for various applications in recent years. HFO - 1132 may exist as a mixture of two geometric isomers (E or trans - isomer and Z or cis - isomer), which may be used separately or together in various ratios. Potential end - uses of HFO - 1132 include refrigerants used alone or in blends with other components, solvents for organic materials, and refrigerants as chemical intermediates in the synthesis of other halogenated hydrocarbon solvents. <00​​​​​​​​This disclosure is based on the discovery that HFO-1132, and in particular HFO-1132E, can be produced from 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) via a catalytic reaction process that generates a controlled amount of a desirable intermediate while minimizing the generation of undesirable byproducts.

[0006] In the first step, 1,1,2-trifluoroethane (HFC-143) is produced by hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) in the presence of a catalyst for producing 1,1,2-trifluoroethane (HFC-143). Next, 1,1,2-trifluoroethane (HFC-143) can be dehydrofluorinated in the presence of a catalyst to produce trans-1,2-difluoroethylene (HFO-1132E) and / or cis-1,2-difluoroethylene (HFO-1132Z). Then, cis-1,2-difluoroethylene (HFO-1132Z) can be isomerized to produce trans-1,2-difluoroethylene (HFO-1132E).

[0007] In one embodiment, the present disclosure provides a method for producing 1,1,2-trifluoroethane (HFC-143), comprising hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) by reaction with hydrogen in the presence of a catalyst comprising palladium or platinum to produce a product mixture, wherein the product mixture comprises, based on the total moles of organic components in the product mixture, at least 30 mol% of 1,1,2-trifluoroethane (HFC-143) and 0.1 mol% to 60 mol% of at least one of 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1-chloro-1,2,2-trifluoroethane (HCFC-133), 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123).

[0008] In another form, the present disclosure provides a method for producing trans-1,2-difluoroethylene (HFO-1132E), comprising defluorinating 1,1,2-trifluoroethane (HFC-143) in the presence of a catalyst selected from fluorinated alumina, palladium supported on fluorinated alumina, fluorinated magnesium oxide, and nickel supported on fluorinated alumina to produce a reaction mixture containing trans-1,2-difluoroethylene (HFO-1132E) and / or cis-1,2-difluoroethylene (HFO-1132Z). [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram of the apparatus used in Example 10A for the conversion of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143). [Figure 2] This is a schematic configuration of the reactor corresponding to Examples 11 to 54. [Modes for carrying out the invention]

[0010] I. Definition Where used herein, the singular forms "a," "an," and "the" include the plural form unless the context explicitly indicates otherwise. Furthermore, when a quantity, concentration, or other value or parameter is given as a range, a preferred range, or an enumeration of upper preferred values ​​and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pair of any upper limit or upper preferred value and any lower limit or lower preferred value, regardless of whether the range is disclosed separately. Where numerical ranges are enumerated herein, unless otherwise specified, the range is intended to include its endpoints, as well as all integers and fractions within the range. The scope of this disclosure is not intended to be limited to the specific values ​​enumerated when defining the range.

[0011] As used herein, the phrase "based on the total moles of organic components of the composition" refers only to carbon-containing components and does not include, or does not include, non-carbon-containing components such as hydrogen (H2) or hydrogen chloride (HCl).

[0012] When used herein, the conversion rate of a reactant molecule (molecule X) during a reaction can be calculated using the following formula: Conversion rate of molecule X % = (100 - moles of molecule X in the organic components of the product mixture)

[0013] When used herein, the selectivity for a molecule (molecule X) formed during the reaction can be calculated using the following formula: Selectivity for molecule X % = Moles of molecule X in the organic component of the product mixture / (100 moles of reactant molecules in the organic component of the product mixture) × 100.

[0014] II. Overview The present invention relates to a method for producing E-1,2-difluoroethylene (HFO-1132E) from 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) according to the following three-step process ("Process 1"), comprising: (i) a step of hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to produce 1,1,2-trifluoroethane (HFC-143); and (ii) 1,1 The present invention provides a method comprising three steps: (iii) dehydrofluorinating ,2-trifluoroethane (HFC-143) to produce a mixture of trans-1,2-difluoroethylene (HFO-1132E) and cis-1,2-difluoroethylene (HFO-1132Z); and (iii) isomerizing cis-1,2-difluoroethylene (HFO-1132Z) to trans-1,2-difluoroethylene (HFO-1132E).

[0015] The following are schematic formulas for the three steps of Process 1. Process 1 (i)CFCl2-CF2Cl(CFC-113)+H2→CFH2-CF2H(HFC-143)+HCl (ii) CFH2 - CF2H → Trans-CFH = CHF(HFO-1132E) + Cis-CFH = CFH(HFO-1132Z) + HF (iii) cis-CFH=CFH(HFO-1132Z) → trans-CFH=CHF(HFO-1132E)

[0016] Step (i) may proceed via a 1,1,2-trifluoroethene intermediate, in which 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) is first hydrogenated to produce 1,1,2-trifluoroethene as an intermediate, and then this intermediate itself is hydrogenated to produce 1,1,2-trifluoroethane (HFC-143).

[0017] Further details regarding each of the processes (i), (ii), and (iii) are provided below.

[0018] III. Process (i) General process The hydrogenation reaction of step (i) may be carried out in the gaseous vapor phase in a suitable reactor, for example, a tubular reactor made of a temperature-resistant and / or corrosion-resistant material such as nickel and its alloys, including Hastelloy (e.g., Hastelloy C276), Inconel (e.g., Inconel 600), Incoloy, and Monel, and the vessel may be lined with a fluoropolymer.

[0019] The reactor may first be cleaned and flushed with an inert gas such as nitrogen, and then packed with a catalyst as described below. The catalyst may be pretreated in the reactor, such as by drying in a manner further described below, and then the reactants may be metered and supplied to the reactor to start the reaction.

[0020] The process flow may be downward or upward through the catalyst bed. The product may be flowed through one or more scrubbers to remove by-products from the reaction, such as hydrogen fluoride (HF) and / or hydrogen chloride (HCl), and the reaction product may be collected, for example, by capture in a cooled cylinder.

[0021] Figure 1 provides a schematic diagram of one process flow illustrating the components suitable for the reaction in step (i). Referring to the process flow diagram 100 shown therein, the supply of nitrogen (N2) acting as an inert carrier is provided from cylinder 102, and the supply of hydrogen (H2) is provided from cylinder 104. The organic feedstock, including 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), is supplied from cylinder 106. Cylinders 102, 104, and 106 are all connected to a KOH scrubber 108 coupled to a vent 110. The N2, H2, and organic feedstocks are supplied into a reactor 112 surrounded by a box oven 114. The reaction can be monitored by taking a sample from outlet 120 and performing GC analysis. As the reaction progresses, the product is supplied to a holding tank 116 which can be immersed in a bath of dry ice or a mixture of dry ice and acetone 118. A dry ice or a mixed bath of dry ice and acetone is configured to maintain the temperature of the holding tank 116 at a low temperature, such as approximately -87°C, which is lower than the ambient temperature. The holding tank 116 is coupled to a buffer knockout tank 122 to prevent potential backflow of the KOH solution, and the buffer knockout tank 122 is also coupled to a KOH scrubber 124. The scrubber 124 has a vent 126 that opens to the atmosphere. The catalyst and process conditions play important roles in the reaction. Specifically, in the hydrogenation step (i), the catalyst may include metals such as palladium, platinum, iron, cobalt, or nickel.

[0022] catalyst The catalyst active in catalyzing the reaction may be palladium metal, platinum metal, or a combination of palladium metal and platinum metal.

[0023] The catalyst can be supported on a suitable carrier such as carbon or alumina. The carbon may be activated carbon. The alumina may be alpha-alumina, theta-alumina, delta-alumina, or gamma-alumina. The supported catalyst can be produced by impregnating one of the suitable carriers with a solution of a compound of the desired metal component. The carrier may also be in the form of pellets. After the impregnation step, the solvent is removed using heat or under vacuum to produce a solid mass, which can be further dried and reduced to form an activated metal catalyst.

[0024] The catalyst may be palladium on a carbon support, platinum on a carbon support, and / or palladium or platinum on an alumina support. In one particularly preferred embodiment, the catalyst is palladium on an alpha-alumina support.

[0025] The amount of metal supported on the carrier may be about 0.01% by weight, about 0.05% by weight, about 0.1% by weight, about 0.2% by weight, about 0.3% by weight, about 0.4% by weight, about 0.5% by weight, or about 1% to about 2% by weight, about 3% by weight, about 5% by weight, about 10% by weight, about 20% by weight, about 30% by weight, about 40% by weight, about 50% by weight, or within any range encompassed by two of the aforementioned values ​​as endpoints. In the case of supported precious metal catalysts such as Pd or Pt, the amount of metal supported may be about 0.01% to about 5% by weight, preferably about 0.05% to about 2% by weight, and more preferably about 0.1% to about 1% by weight.

[0026] When using a palladium catalyst, the amount of palladium supported on a support such as an alpha-alumina support may be about 0.01% to about 5% by weight, preferably about 0.05% to about 2% by weight, and more preferably about 0.1% to about 1% by weight.

[0027] The catalyst used in step (i) may have a suitable BET (Brunauer, Emmet, and Teller) surface area. In some embodiments, the BET surface area of ​​the catalyst is as low as about 1 m².2 / g, about 3 m 2 / g, about 5 m 2 / g, about 10 m 2 / g, about 15 m 2 / g, about 20 m 2 / g 2 , about 30 m 2 / g, about 40 m 2 / g, about 50 m 2 / g, about 100 m 2 / g, about 200 m 2 / g, or as high as about 250 m 2 / g, about 300 m 2 / g, about 400 m 2 / g, about 500 m 2 / g, about 600 m 2 / g, about 700 m 2 / g m 2 , about 800 m 2 / g, about 900 m 2 / g, about 1000 m 2 / g, about 2000 m 2 / g, or may be within any range included by any of the aforementioned values as endpoints.

[0028] In the case of an alumina-supported metal catalyst, the BET surface area is about 1 m 2 / g to about 500 m 2 / g, preferably about 1 m 2 / g to about 200 m 2 / g, more preferably about 1 m 2 / g to about 100 m 2 / g, and most preferably about 1 m 2 / g to about 20 m 2 / g may be.

[0029] When a palladium catalyst is used on an alpha-alumina support, the BET surface area is about 1 m 2 / g to about 500 m 2 / g, preferably about 1 m 2 / g to about 200 m 2 / g, more preferably about 1 m 2 / g to about 100 m 2 / g, and most preferably about 1 m 2 / g to about 20 m 2 / g is also acceptable.

[0030] BET analysis is a standard method for determining surface area from nitrogen adsorption isotherms. The BET surface area of ​​a catalyst can be measured using the TriStar II Micromeritics instrument. Catalyst samples are degassed before analysis using the FlowPrep 060 instrument.

[0031] Catalytic pretreatment The catalyst may be pretreated by various methods to improve its performance and effectiveness in the reaction. For example, the catalyst may be dried at high temperatures ranging from as low as about 200°C, 250°C, 300°C, 350°C, 360°C, 370°C, or as high as about 380°C, 390°C, 400°C, 450°C, 500°C, 600°C, 700°C, or any range encompassed by two of the aforementioned values ​​as endpoints. As part of the catalyst pretreatment, the catalyst may be exposed to an inert gas such as N2. The pretreatment process may be as short as about 1 hour, 2 hours, 3 hours, or as long as about 4 hours, 5 hours, 6 hours, 10 hours, 20 hours, or any range encompassed by two of the aforementioned values ​​as endpoints, such as 2 hours to 4 hours.

[0032] When using a palladium catalyst on an alpha-alumina support, the catalyst may be dried at a temperature of approximately 200°C to approximately 700°C, preferably approximately 200°C to approximately 500°C, and most preferably approximately 200°C to approximately 300°C.

[0033] When a palladium catalyst is used on an alpha-alumina support, the catalyst may be exposed to an inert gas such as N2 for about 1 to 20 hours, preferably about 1 to 10 hours, and most preferably about 1 to 3 hours.

[0034] Reaction conditions The reaction temperature may be as low as about 100°C, about 125°C, about 150°C, about 200°C, about 250°C, or as high as about 300°C, about 350°C, about 400°C, or any range encompassed by any two of the aforementioned endpoints, such as about 100°C to about 250°C, or about 150°C to about 200°C. The temperature may preferably be about 100°C to about 300°C, and more preferably about 150°C to about 250°C.

[0035] When a palladium catalyst is used on an alpha-alumina support, the reaction temperature may be about 100°C to about 400°C, preferably about 100°C to about 300°C, and most preferably about 150°C to about 250°C.

[0036] As demonstrated by the examples herein, the selectivity for the desired product 1,1,2-trifluoroethane (HFC-143) can increase with temperature. However, the overall selectivity for 1,1,2-trifluoroethane (HFC-143) and its associated recyclable intermediates (such as 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1-chloro-1,2,2-trifluoroethane (HCFC-133), 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123)) is less than that for ethane. The performance may decrease at high temperatures due to an increased formation of undesirable by-products such as HC-170, chloroethane (HCC-160), chlorodifluoroethane (1-chloro-2,2-difluoroethane (HCFC-142), 1-chloro-1,1-difluoroethane (HCFC-142b), and 1-chloro-1,2-difluoroethane (HCFC-142a), etc.), and 1,1,1-trifluoroethane (HFC-143a).

[0037] The contact time between the reactant and the catalyst may be as short as about 0.1 seconds, about 1 second, about 5 seconds, about 10 seconds, about 15 seconds, or about 20 seconds, or as long as about 25 seconds, about 30 seconds, about 40 seconds, about 50 seconds, about 60 seconds, or about 120 seconds, or any approximate range or range encompassed by two of the aforementioned values ​​as endpoints. For example, the contact time may preferably be between about 1 second and about 60 seconds.

[0038] When using a palladium catalyst on an alpha-alumina support, the contact time may be about 1 second to about 60 seconds, preferably about 5 seconds to about 40 seconds, and most preferably about 10 seconds to about 30 seconds.

[0039] The pressure may be as low as about 1 psig, about 3 psig, about 5 psig, about 10 psig, about 15 psig, about 20 psig, about 30 psig, about 35 psig, or about 40 psig, or as high as about 90 psig, about 100 psig, about 120 psig, about 150 psig, about 200 psig, or about 250 psig, or about 300 psig, or within any range encompassed by two of the aforementioned values ​​as endpoints. For example, the pressure may preferably be between about 10 psig and about 100 psig.

[0040] When using a palladium catalyst on an alpha-alumina support, the pressure may be about 1 psig to about 300 psig, preferably about 1 psig to about 200 psig, and most preferably about 10 psig to about 100 psig.

[0041] The molar ratio of hydrogen to 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) may be, for example, as small as about 2:1, about 3:1, about 4:1, about 5:1, about 5.5:1, or as large as about 6:1, about 6.5:1, about 7.5:1 or about 8:1, about 12:1, about 15:1 or about 20:1, or within any range encompassed by two of the aforementioned values ​​as endpoints. The molar ratio of hydrogen to CFC-113 may preferably be about 3:1 to about 15:1, and more preferably about 4:1 to about 10:1.

[0042] When a palladium catalyst is used on an alpha-alumina support, the molar ratio of hydrogen to 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) can be about 2:1 to about 20:1, preferably about 3:1 to about 15:1, and most preferably about 4:1 to about 10:1.

[0043] product The hydrogenation step (step (i)) involves, in the reactor, the desired product 1,1,2-trifluoroethane (HFC-143) and desired intermediates such as 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1-chloro-1,2,2-trifluoroethane (HCFC-133), 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123), and 1,1-difluoroethane (HF A product mixture may be produced that includes undesirable by-products such as C-152a), ethane (HC-170), chloroethane (HCC-160), chlorodifluoroethane (1-chloro-2,2-difluoroethane (HCFC-142), 1-chloro-1,1-difluoroethane (HCFC-142b), and 1-chloro-1,2-difluoroethane (HCFC-142a), etc.), and 1,1,1-trifluoroethane (HFC-143a).

[0044] As demonstrated by the examples herein, the hydrogenation step may have selectivity for 1,1,2-trifluoroethane (HFC-143) products in a range of over 20%, over 30%, over 40%, over 50%, over 60%, over 70%, over 80%, over 90%, or any range encompassed by two of the aforementioned values ​​as endpoints.

[0045] When a palladium catalyst is used on an alpha-alumina support, the hydrogenation step may achieve a selectivity for 1,1,2-trifluoroethane (HFC-143) products of more than about 20%, preferably more than about 30%, and most preferably more than 40%.

[0046] The hydrogenation reaction can also produce several intermediates, including 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1-chloro-1,2,2-trifluoroethane (HCFC-133), and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123). These intermediates are recyclable and can ultimately be converted to 1,1,2-trifluoroethane (HFC-143).

[0047] As demonstrated by the examples herein, the hydrogenation step may achieve combined selectivity and / or selectivity for each of 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a) in any range encompassed by more than about 30%, more than about 40%, more than about 50%, more than about 60%, more than about 70%, more than about 80%, more than about 90%, more than about 95%, or any range encompassed by two of the aforementioned values ​​as endpoints.

[0048] When a palladium catalyst is used on an alpha-alumina support, the hydrogenation step may achieve a combined selectivity and / or selectivity for each of 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a) of about 30%, preferably about 40%, and most preferably about 50%.

[0049] The hydrogenation reaction may also produce several by-products, such as 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), 1,1-difluoroethylene (HFO-1132a), chlorodifluoroethane (1-chloro-2,2-difluoroethane (HCFC-142), 1-chloro-1,1-difluoroethane (HCFC-142b), and 1-chloro-1,2-difluoroethane (HCFC-142a)), and chloroethane (HCC-160), which are the result of hydrogenation-dehalogenation side reactions. These by-products are undesirable because they are difficult to recycle or convert to 1,1,2-trifluoroethane (HFC-143). As demonstrated by the examples herein, the hydrogenation step may achieve composite selectivity and / or selectivity for each of 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), chlorodifluoroethane (such as 1-chloro-2,2-difluoroethane (HCFC-142), 1-chloro-1,1-difluoroethane (HCFC-142b), and 1-chloro-1,2-difluoroethane (HCFC-142a)), and chloroethane (HCC-160), in any range encompassed by two of the aforementioned values ​​as endpoints, such as less than about 30%, less than about 25%, less than about 20%, less than about 15%, less than about 10%, less than about 9%, less than about 8%, less than about 7%, less than about 6%, less than 5%, or any range encompassed by two of the aforementioned values ​​as endpoints.

[0050] When a palladium catalyst is used on an alpha-alumina support, the hydrogenation step may achieve a combined selectivity and / or selectivity for each of the following: 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), chlorodifluoroethane (such as 1-chloro-2,2-difluoroethane (HCFC-142), 1-chloro-1,1-difluoroethane (HCFC-142b), and 1-chloro-1,2-difluoroethane (HCFC-142a)), and chloroethane (HCC-160), in amounts of less than 30%, preferably less than 25%, and most preferably less than 20%.

[0051] As demonstrated by the examples herein, the hydrogenation step may achieve a conversion rate of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) of, for example, more than about 10%, more than about 20%, more than about 30%, more than about 40%, more than about 50%, more than about 60%, more than about 75%, more than about 90%, more than about 95%, more than about 97%, or higher, or any range encompassed by two of the aforementioned values ​​as endpoints.

[0052] When a palladium catalyst is used on an alpha-alumina support, the hydrogenation step may achieve a conversion rate of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) of more than 10%, preferably more than 20%, and most preferably more than 30%.

[0053] After using the catalyst in the reactor for an extended period, it may also be beneficial to periodically regenerate the catalyst. Catalyst regeneration can be achieved by any means known in the art, for example, by passing air or air diluted with nitrogen over the catalyst at a temperature of about 100°C to about 400°C, preferably about 200°C to about 375°C, for about 0.5 hours to about 3 days. Subsequently, carbon and alumina-supported metal catalysts may be subjected to hydrogen treatment at a temperature of about 100°C to about 400°C, preferably about 200°C to about 350°C.

[0054] When a palladium catalyst is used on an alpha-alumina support, one or more of the following properties may be present. The amount of palladium supported on the support may be about 0.01% to about 5% by weight, preferably about 0.05% to about 2% by weight, and more preferably about 0.1% to about 1% by weight. The BET surface area is about 1 m². 2 / g~about 500m 2 / g, preferably about 1m 2 / g~about 200m 2 / g, comfortably about 1m 2 / g~about 100m 2 / g, and most preferably about 1m 2 / g~about 20m 2 The amount may be / g. The catalyst may be dried at a temperature of about 200°C to about 700°C, preferably about 200°C to about 500°C, most preferably about 200°C to about 300°C. The catalyst may be exposed to an inert gas such as N2 for about 1 hour to about 20 hours, preferably about 1 hour to about 10 hours, most preferably about 1 hour to about 3 hours. The reaction temperature may be about 100°C to about 400°C, preferably about 100°C to about 300°C, most preferably about 150°C to about 250°C. The contact time may be about 1 second to about 60 seconds, preferably about 5 seconds to about 40 seconds, most preferably about 10 seconds to about 30 seconds. The pressure may be about 1 psig to about 300 psig, preferably about 1 psig to about 200 psig, most preferably about 10 psig to about 100 psig. The molar ratio of hydrogen to 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) may be about 2:1 to about 20:1, preferably about 3:1 to about 15:1, and most preferably about 4:1 to about 10:1.

[0055] The hydrogenation step may achieve selectivity for 1,1,2-trifluoroethane (HFC-143) products of more than 20%, preferably more than 30%, and most preferably more than 40%.

[0056] The hydrogenation step may achieve a combined selectivity and / or selectivity for each of 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), and 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a) of about 30%, preferably about 40%, and most preferably about 50%.

[0057] The hydrogenation step may achieve a combined selectivity and / or selectivity for each of the following: 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), chlorodifluoroethane (such as 1-chloro-2,2-difluoroethane (HCFC-142), 1-chloro-1,1-difluoroethane (HCFC-142b), and 1-chloro-1,2-difluoroethane (HCFC-142a)), and chloroethane (HCC-160), in amounts of less than 30%, preferably less than 25%, and most preferably less than 20%.

[0058] The hydrogenation step may achieve a conversion rate of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143) of more than 10%, preferably more than 20%, and most preferably more than 30%.

[0059] In the process described above, referring to Figure 1, the amount of 1,1,2-trifluoroethane (HFC-143) in the product mixture may be, for example, at least 30 mol%, at least 50 mol%, or at least 70 mol%, based on the total moles of the organic components in the product mixture.

[0060] The amount of 1-chloro-1,1,2-trifluoroethane (HCFC-133b) in the product mixture, if present, may be greater than 0.1 mol%, and moreover less than 60 mol%, less than 30 mol%, or less than 10 mol%, for example, 0.1 mol% to 60 mol%, 0.1 mol% to 30 mol%, or 0.1 mol% to 10 mol%, based on the total moles of the organic components in the product mixture.

[0061] The amount of 1-chloro-1,2,2-trifluoroethane (HCFC-133) in the product mixture, if present, may be greater than 0.1 mol%, and moreover less than 20 mol%, less than 10 mol%, or less than 5 mol%, for example, 0.1 mol% to 20 mol%, 0.1 mol% to 10 mol%, or 0.1 mol% to 5 mol%, based on the total moles of the organic components in the product mixture.

[0062] The amount of 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a) in the product mixture, if present, may be greater than 0.1 mol%, and moreover less than 20 mol%, less than 10 mol%, or less than 5 mol%, for example, 0.1 mol% to 20 mol%, 0.1 mol% to 10 mol%, or 0.1 mol% to 5 mol%, based on the total moles of organic components in the product mixture.

[0063] The total amount of 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1-chloro-1,2,2-trifluoroethane (HCFC-133), 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123) in the product mixture may be, for example, at least 60 mol%, at least 70 mol%, or at least 90 mol%, based on the total moles of organic components in the product mixture.

[0064] The total amount of 1,1-difluoroethane (HFC-152a) in the product mixture, if present, may be greater than 0.1 mol% and less than 10 mol%, less than 5 mol%, or less than 1 mol%, for example, 0.1 mol% to 10 mol%, 0.1 mol% to 5 mol%, or 0.1 mol% to 1 mol%, based on the total moles of organic components in the product mixture.

[0065] The total amount of ethane (HC-170) in the product mixture, if present, may be greater than 0.1 mol% and less than 5 mol%, less than 3 mol%, or less than 1 mol%, for example, 0.1 mol% to 5 mol%, 0.1 mol% to 3 mol%, or 0.1 mol% to 1 mol%, based on the total moles of organic components in the product mixture.

[0066] The total amount of chloroethane (HCC-160) in the product mixture, if present, may be greater than 0.1 mol% and less than 3 mol%, less than 2 mol%, or less than 1 mol%, for example, 0.1 mol% to 3 mol%, 0.1 mol% to 2 mol%, or 0.1 mol% to 1 mol%, based on the total moles of organic components in the product mixture.

[0067] The total amount of chlorodifluoroethane (such as 1-chloro-2,2-difluoroethane (HCFC-142), 1-chloro-1,1-difluoroethane (HCFC-142b), and 1-chloro-1,2-difluoroethane (HCFC-142a)) in the product mixture, if present, may be greater than 0.1 mol% and less than 3 mol%, less than 2 mol%, or less than 1 mol%, for example, based on the total moles of organic components in the product mixture.

[0068] The total amount of 1,1,1-trifluoroethane (HFC-143a) in the product mixture, if present, may be greater than 0.1 mol% and less than 3 mol%, less than 2 mol%, or less than 1 mol%, for example, 0.1 mol% to 3 mol%, 0.1 mol% to 2 mol%, or 0.1 mol% to 1 mol%, based on the total moles of organic components in the product mixture.

[0069] IV. Process (ii) General process The dehydrofluorination reaction of step (ii) may be carried out in the vapor phase in a suitable reactor, for example, a tubular reactor made of a temperature-resistant and / or corrosion-resistant material such as nickel and its alloys, including Hastelloy (e.g., Hastelloy C276), Inconel (e.g., Inconel 600), Incoloy, and Monel, and the vessel may be lined with a fluoropolymer.

[0070] The reactor may first be cleaned and flushed with an inert gas such as nitrogen, and then packed with a catalyst as described below. The catalyst may be pretreated in the reactor, such as by drying in a manner further described below, and then the reactants may be metered and supplied to the reactor to start the reaction.

[0071] The process flow may be downward or upward through the catalyst bed. The reactants may be flowed through a scrubber to remove by-products from the reaction, such as hydrogen fluoride (HF) and / or hydrogen chloride (HCl), and the reaction products may be collected, for example, by capture in a cooled cylinder.

[0072] catalyst The catalyst and process conditions play a crucial role in the dehydrofluoridation reaction.

[0073] Suitable catalysts for dehydrofluorination reactions include metal oxides such as chromium oxide, aluminum oxide, iron oxide, and magnesium oxide. Fluorination of the catalyst may be carried out using anhydrous HF under conditions effective for converting a portion of the metal oxide to the corresponding metal fluoride, for example, via the procedure disclosed in U.S. Patent No. 6,780,815 by Cerri et al., the disclosure of which is expressly incorporated herein by reference. Other suitable catalysts for dehydrofluorination reactions include metal fluorides such as chromium fluoride, alumina fluoride, iron fluoride, magnesium fluoride, and various combinations thereof.

[0074] Other metals such as Pd, Pt, and Ni can also be supported on the fluorinated metal oxides, for example, via a wet impregnation process in which a salt of the metal is exposed to a fluorinated metal oxide support in a solution, followed by drying and then reduction with hydrogen gas.

[0075] The amount of metal supported on the carrier may be in the range of about 0.01% by weight, about 0.05% by weight, about 0.1% by weight, about 0.2% by weight, about 0.3% by weight, about 0.4% by weight, about 0.5% by weight, or about 1% to about 2% by weight, about 3% by weight, 5% by weight, 10% by weight, or 20% by weight, or 30% by weight, or 40% by weight, or 50% by weight, or any range encompassed by two of the aforementioned values ​​as endpoints. In the case of supported precious metal catalysts such as platinum or palladium, the amount of metal supported may be in the range of about 0.01% to about 5% by weight, preferably about 0.05% to about 2% by weight, and more preferably about 0.1% to about 1% by weight.

[0076] When using fluorinated alumina, the amount of metal supported on the carrier may be about 0.01% to about 5% by weight, preferably about 0.05% to about 2% by weight, and most preferably about 0.1% to about 1% by weight.

[0077] The catalyst used in step (ii) may have a suitable BET (Brunauer, Emmet, and Teller) surface area. In some embodiments, the BET surface area of ​​the catalyst is as low as about 10 m². 2 / g, about 20m 2 / g, approx. 30m 2 / g, approx. 40m 2 / g, approx. 50m 2 / g, approx. 60m 2 / g, approx. 70m 2 / g, approx. 80m 2 / g, approx. 90m 2 / g, about 100m 2 / g, or at most about 110m 2 / g, approx. 120m 2 / g, approx. 130m 2 / g, approx. 140m 2 / g, approx. 150m 2 / g, approx. 175m 2 / g, approx. 200m 2 / g, approx. 225m 2 / g, approx. 250m 2 / g, approx. 300m 2It may be within any range encompassed by either / g or the aforementioned value as an endpoint. For metal oxide catalysts, the BET surface area is preferably about 100 m². 2 The concentration may exceed / g. For fluorinated metal oxide catalysts, the BET surface area is preferably about 20 m². 2 It may be greater than / g. BET analysis is a standard method for determining surface area from nitrogen adsorption isotherms. The BET surface area of ​​the catalyst can be measured using the TriStar II Micromeritics instrument. The catalyst sample is degassed before analysis using the FlowPrep 060 instrument.

[0078] When using fluorinated alumina, the BET surface area is approximately 10 m². 2 More than / g, preferably 20m 2 More than / g, most preferably 25m 2 It's okay if it exceeds / g.

[0079] Catalytic pretreatment The catalyst may be pretreated by drying at a high temperature of approximately 200°C, 250°C, 300°C, 350°C, 360°C, 370°C, or 380°C, 390°C, 400°C, 450°C, 500°C, 550°C, 600°C, or any range encompassed by two of the aforementioned values ​​as endpoints. As part of catalyst activation, the catalyst may be exposed to an inert gas such as N2. The pretreatment process may be as short as approximately 1 hour, 2 hours, 3 hours, or as long as approximately 4 hours, 5 hours, 6 hours, 10 hours, 20 hours, or any range encompassed by two of the aforementioned values ​​as endpoints, such as approximately 2 hours to 4 hours.

[0080] When using alumina fluoride, the catalyst may be pretreated by drying at a temperature of about 200°C to about 600°C, preferably about 300°C to about 600°C, and most preferably about 400°C to about 550°C.

[0081] When using fluorinated alumina, the pretreatment process may take about 1 to 10 hours, preferably about 2 to 6 hours, and most preferably about 3 to 5 hours.

[0082] Reaction conditions The temperature range for the defluoride hydrogenation reaction may be as low as about 125°C, about 150°C, about 200°C, about 250°C, about 300°C, about 350°C, about 400°C, about 450°C, or as high as about 500°C, about 550°C, about 600°C, about 650°C, about 700°C, about 750°C, about 800°C, or any range encompassed by two of the aforementioned values ​​as endpoints. The temperature may preferably be about 250°C to about 450°C, and more preferably about 300°C to about 400°C.

[0083] When using alumina fluoride, the reaction temperature may be approximately 125°C to approximately 500°C, preferably approximately 250°C to approximately 450°C, and most preferably approximately 300°C to approximately 400°C.

[0084] The pressure may be as low as about 1 psig, about 2 psig, about 3 psig, about 4 psig or about 5 psig, about 10 psig, about 15 psig, about 20 psig, about 25 psig, about 30 psig, about 35 psig, about 40 psig, about 50 psig, or any range encompassed by two of the aforementioned values ​​as endpoints. For example, the pressure may be about 1 psig to about 50 psig, preferably about 5 psig to about 30 psig, and more preferably about 10 psig to about 20 psig.

[0085] When using alumina fluoride, the reaction pressure may be about 1 psig to about 50 psig, preferably about 5 psig to about 30 psig, and most preferably about 10 psig to about 20 psig.

[0086] The contact time between the reactant and the catalyst may be as short as approximately 0.1 seconds, 1 second, 5 seconds, 10 seconds, 15 seconds, or 20 seconds, or as long as approximately 25 seconds, 30 seconds, 40 seconds, 50 seconds, 60 seconds, or 120 seconds, or any approximate range encompassed by two of the aforementioned endpoints. For example, the contact time may be between approximately 1 second and 60 seconds.

[0087] When using alumina fluoride, the contact time may be about 1 second to about 60 seconds, preferably about 5 seconds to about 40 seconds, and most preferably about 10 seconds to about 30 seconds.

[0088] The reaction may also be carried out in substantially the absence of water. For example, the amount of water present during the reaction may be less than 1 mol%, less than 0.5 mol%, or less than 0.05 mol%, based on the total weight of the reactants in the reactor.

[0089] product In the dehydrofluoridation reaction of step (ii), the cis / trans molar ratio of 1,2-difluoroethylene in the product mixture may be as low as about 1, about 2, about 3, about 4, about 5, about 6, or as high as about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, about 15, or any range encompassed by two of the aforementioned values ​​as endpoints. For example, the cis / trans ratio may be between about 2 and about 15.

[0090] When using alumina fluoride, the cis / trans molar ratio of 1,2-difluoroethylene in the product mixture may be about 1 to about 15, preferably about 1 to about 10, and most preferably about 2 to about 7.

[0091] The selectivity for the desired 1,2-difluoroethylene product (total of 1232E and 1232Z) may be as low as about 80%, about 85%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, or as high as about 96%, about 97%, about 98%, about 99%, or any range encompassed by two of the aforementioned values ​​as endpoints. For example, the selectivity may be about 89% to about 99%.

[0092] When using alumina fluoride, the selectivity for the desired 1,2-difluoroethylene product (total of 1232E and 1232Z) may be about 85% to about 99%, preferably about 90% to about 99%, and most preferably about 95% to about 99%.

[0093] The conversion rate of the starting material to 1,2-difluoroethylene may be greater than approximately 10%, greater than approximately 20%, greater than approximately 30%, greater than approximately 40%, greater than approximately 50%, greater than approximately 60%, greater than approximately 70%, greater than approximately 80%, greater than approximately 90%, greater than approximately 95%, greater than approximately 99%, or any range encompassed by two of the aforementioned values ​​as endpoints.

[0094] When using fluorinated alumina, the conversion rate of the starting material to 1,2-difluoroethylene may be more than about 20%, preferably more than about 30%, and most preferably more than about 60%.

[0095] After using the catalyst in the reactor for an extended period, it is also beneficial to periodically regenerate the catalyst. Catalyst regeneration can be achieved by any means known in the art, for example, by passing air or air diluted with nitrogen over the catalyst at a temperature of about 100°C to about 400°C, preferably about 200°C to about 375°C, for about 0.5 hours to about 3 days. This may be followed by a hydrogen fluoride treatment at a temperature of about 100°C to about 400°C, preferably about 200°C to about 350°C, for fluorinated catalysts, or a hydrogen treatment at a temperature of about 100°C to about 400°C, preferably about 200°C to about 350°C, for supported transition metal catalysts.

[0096] When using fluorinated alumina, the catalyst can be regenerated by passing air or nitrogen-diluted air over the catalyst at a temperature of about 100°C to about 400°C, preferably about 200°C to about 375°C, for about 0.5 hours to about 3 days. This may be followed by a hydrogen fluoride treatment at a temperature of about 100°C to about 400°C, preferably about 200°C to about 350°C. Additionally, this process advantageously avoids and / or minimizes the formation of 1,1,1-trifluoroethane (HFC-143a), and the product of step (ii) containing trans-1,2-difluoroethylene (HFO-1132E) may contain less than 5% by weight, less than 3% by weight, less than 1% by weight, less than 0.5% by weight, or less than 0.1% by weight of 1,1,1-trifluoroethane (HFC-143a), based on the total weight of the product composition.

[0097] When using alumina fluoride as a catalyst, the following properties may exist: The amount of metal supported on the carrier may be about 0.01% to about 5% by weight, preferably about 0.05% to about 2% by weight, and most preferably about 0.1% to about 1% by weight. The BET surface area is about 10 m². 2 More than / g, preferably 20m 2 More than / g, most preferably 25m 2The amount may be greater than / g. The catalyst may be pretreated by drying at a temperature of about 200°C to about 600°C, preferably about 300°C to about 600°C, most preferably about 400°C to about 550°C. The pretreatment process may take about 1 hour to about 10 hours, preferably about 2 hours to about 6 hours, most preferably about 3 hours to about 5 hours. The reaction temperature may be about 125°C to about 500°C, preferably about 250°C to about 450°C, most preferably about 300°C to about 400°C. The reaction pressure may be about 1 psig to about 50 psig, preferably about 5 psig to about 30 psig, most preferably about 10 psig to about 20 psig. The contact time may be about 1 second to about 60 seconds, preferably about 5 seconds to about 40 seconds, most preferably about 10 seconds to about 30 seconds. The cis / trans molar ratio of 1,2-difluoroethylene in the product mixture may be about 1 to about 15, preferably about 1 to about 10, and most preferably about 2 to about 7. The selectivity for the desired 1,2-difluoroethylene product (total of 1232E and 1232Z) may be about 85% to about 99%, preferably about 90% to about 99%, and most preferably about 95% to about 99%. The conversion rate of the starting material to 1,2-difluoroethylene may be greater than about 20%, preferably greater than about 30%, and most preferably greater than about 60%. The catalyst can be regenerated by passing air or air diluted with nitrogen over the catalyst at a temperature of about 100°C to about 400°C, preferably about 200°C to about 375°C, for about 0.5 hours to about 3 days. Following this regeneration, a hydrogen fluoride treatment may be carried out at a temperature of about 100°C to about 400°C, preferably about 200°C to about 350°C.

[0098] In the above process, the amount of trans-1,2-difluoroethylene (HFO-1132E) in the product mixture may be, for example, at least 5 mol%, at least 10 mol%, or at least 20 mol%, based on the total moles of organic components in the product mixture.

[0099] In the above process, the amount of cis-1,2-difluoroethylene (HFO-1132Z) in the product mixture may be, for example, at least 60 mol%, at least 80 mol%, or at least 90 mol%, based on the total moles of organic components in the product mixture.

[0100] The total amount of 1,1,1-trifluoroethane (HFC-143a) in the product mixture, if present, may be greater than 0.01 mol% and less than 10 mol%, less than 5 mol%, or less than 1 mol%, for example, 0.01 mol% to 10 mol%, 0.01 mol% to 5 mol%, or 0.01 mol% to 1 mol%, based on the total moles of organic components in the product mixture.

[0101] The total amount of fluoroethylene in the product mixture, if present, may be greater than 0.1 mol% and less than 10 mol%, less than 5 mol%, or less than 1 mol%, for example, 0.1 mol% to 10 mol%, 0.1 mol% to 5 mol%, or 0.1 mol% to 1 mol%, based on the total moles of the organic components in the product mixture.

[0102] V. Process (iii) General process The 1,2-difluoroethylene (HFO-1132) obtained in step (ii) above may be produced as a mixture containing both isomers of trans-1,2-difluoroethylene (HFO-1132E) and cis-1,2-difluoroethylene (HFO-1132Z).

[0103] In step (iii), the cis-1,2-difluoroethylene (HFO-1132Z) isomer may be converted to the trans-1,2-difluoroethylene (HFO-1132E) isomer by either heat and / or exposure to a catalyst to obtain a final product containing, essentially consisting of, or comprising the trans-1,2-difluoroethylene (HFO-1132E) isomer in high purity, such as at least about 95% by weight, at least about 99.0% by weight, at least about 99.9% by weight, or at least about 99.99% by weight or more.

[0104] The isomerization reaction may be carried out in any suitable reaction vessel or reactor, but preferably it should be made of corrosion-resistant material such as nickel and its alloys, including Hastelloy (e.g., Hastelloy C276), Inconel (e.g., Inconel 600), and Monel, and the vessel may be lined with a fluoropolymer. These may be a single pipe or a number of tubes filled with the isomerization catalyst.

[0105] Reaction conditions The temperature range for the isomerization reaction may be as low as approximately 100°C, 150°C, 200°C, 250°C, 300°C, 350°C, 400°C, or 450°C, or as high as approximately 500°C, 550°C, 600°C, 650°C, 700°C, 750°C, or 800°C, or any range encompassed by two of the aforementioned values ​​as endpoints.

[0106] The reaction can be carried out under atmospheric pressure, superpressure, or vacuum. The vacuum pressure can range from approximately 5 Torr to approximately 760 Torr. The contact time between the reactants and the catalyst can range from approximately 0.5 seconds to approximately 120 seconds, but longer or shorter times can be used.

[0107] The reaction may also be carried out in an inert atmosphere in the substantially absence of oxygen. For example, the amount of oxygen present during the reaction may be less than 10 mol%, less than 5 mol%, or less than 1 mol%, based on the total weight of the reactants in the reactor.

[0108] The reaction may also be carried out in substantially the absence of water. For example, the amount of water present during the reaction may be less than 1 mol%, less than 0.5 mol%, or less than 0.05 mol%, based on the total weight of the reactants in the reactor.

[0109] Where used herein, the phrase "any range encompassing any two of these values ​​as endpoints" literally means that any range can be selected from any two of the values ​​listed before such phrase, regardless of whether the values ​​are in the lower or higher part of the enumeration. For example, a pair of values ​​could be selected from two lower values, two higher values, or a lower value and a higher value.

[0110] It should be understood that the foregoing description is merely illustrative of the present disclosure. Various alternative and modified forms can be devised by those skilled in the art without departing from the present disclosure. Accordingly, the present disclosure is intended to encompass all such alternative forms, modifications, and variations that fall within the scope of the appended claims. [Examples]

[0111] Examples 1-10 Step 1 - Hydrogenation of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to produce 1,1,2-trifluoroethane (HFC-143) Examples 1-10 below were carried out according to the following procedure. A 1 / 2-inch Iconel tubular reactor was cleaned and flushed, and then packed with a specific amount of catalyst. The catalyst was then pretreated as described below, and the tubular reactor was heated in a 250°C oven for at least 2 hours while flowing nitrogen at atmospheric pressure to reach the aforementioned temperature, after which the nitrogen flow was stopped. After reaching the desired temperature, the reactants were flowed into the tubular reactor at the desired pressure and flow rate for approximately 1 hour. After this step, the reactants were passed through a scrubber to remove HF and HCl. The reaction products were then collected in a cylinder cooled with dry ice. The products were analyzed by gas chromatography (GC), and the reaction selectivity and conversion rate were calculated.

[0112] In Examples 1-4 and 10 below, 100 g of 3 x 5 mm activated carbon pellets were stirred in water at 80°C for 24 hours with 1.7 g of stoichiometric amount of palladium(II) chloride (Sigma Aldrich), followed by filtration and washing with distilled water to obtain 1% by weight of Pd on the carbon. The sample was then dried at 100°C and reduced by a hydrogen stream at 250°C for 2 hours.

[0113] In Example 5, 1 wt% platinum on granular carbon was obtained from Sigma-Aldrich. In Example 6, 0.5 wt% platinum on 3.2 mm alumina pellets was obtained from Sigma-Aldrich. In Examples 7-9, Alloy 200 0.24 inch Propak catalyst, a metal packing made from Nickel 200 (99.6% nickel alloy), was obtained from Cannon Instrument.

[0114] Table 1 below provides the reaction conditions for each example, and Table 2 provides an overview of the product mixture.

[0115] [Table 1]

[0116] The reactions in Table 1 yielded the product mixtures shown in Table 2 below.

[0117] [Table 2-1]

[0118] [Table 2-2]

[0119] [Table 2-3]

[0120] Example 10A: Performance of palladium / alumina catalyst Example 10A demonstrated the performance of a Pd / Al2O3 catalyst for the conversion rate of CFC-113 to R-143. The experimental apparatus used in this example is shown in Figure 1 and described above. The apparatus included a supply system including gas flow control devices for N2 and H2, and a Micromotion mass flow meter connected to a research control valve (RCV) for controlling the flow rate of organic matter. The reactor consisted of a 1-inch SS tube filled with catalyst. A thermocouple was inserted into the center of the catalyst bed to read the operating temperature. The pressure control system consisted of an RCV that controlled the pressure by receiving feedback from a pressure transducer located behind the reactor. For GC analysis, samples were taken from the reactor using a sample bag filled with 50 mL of water to capture HCl and HF. Prior to GC analysis, the sample bag was heated at 60°C for 1 hour to ensure that all organic contents were in the vapor phase. The sample was then taken using a syringe and injected into the GC instrument for analysis. Table 3 shows the process of conversion of CFC-113 to R-143, 3.9m 2 The conversion rate and selectivity of an undiluted 0.2% Pd / α-Al2O3 catalyst with a BET surface area of ​​1 / g are shown. Selectivity for HFC-143 increased with temperature, but overall selectivity for HFC-143 + recyclable materials decreased with temperature due to increased formation of undesirable byproducts such as ethane, chlorodifluoroethane (HCFC-142, HCFC-142b, and HCFC-142a, etc.), HFC-143a, and HCC-160.

[0121] In Table 3 below, the product / intermediate may include further recyclable components such as 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123). These components are considered recyclable in that they can be recycled into the inputs of step (i) and ultimately converted to 1,1,2-trifluoroethane (HFC-143).

[0122] In Table 3 below, the by-products may include 1,1-difluoroethane (HFC-152a), ethane (HC-170), 1,1,1-trifluoroethane (HFC-143a), 1,1-difluoroethylene (HFO-1132a), 1-chloro-1,1-difluoroethane (HCFC-142b), chlorodifluoroethane (HCFC-142, HCFC-142b, and HCFC-142a, etc.), and chloroethane (HCC-160). These by-products are the result of the dehydrofluoridation side reaction and are difficult to recycle or convert to 1,1,2-trifluoroethane (HFC-143). Therefore, they can be separated from the products of the reaction in step (i) for proper disposal. For the reactions shown in Table 3, the catalyst volume was 50 mL, the reactor pressure was 45 psig, the H2 flow rate was 150 mL / min, and the HFC-113 flow rate was 10 g / h.

[0123] [Table 3]

[0124] The results in Table 3 show that the selectivity for HFC-143 increased with temperature, while the overall selectivity for HFC-143+ recyclable material decreased with temperature due to the increased formation of undesirable by-products such as ethane, chlorodifluoroethane, HFC-143a, and HCC-160.

[0125] Examples 11-54 Step 2: Defluoride of 1,1,2-trifluoroethane (HFC-143) to produce trans-1,2-difluoroethylene (HFO-1132E) and cis-1,2-difluoroethylene (HFO-1132Z). Referring to Figure 2, Examples 11-54 below were carried out in reactor 112 according to the following procedure. A 1 / 2-inch Inconel tubular reactor 132 was cleaned and flushed, and then packed with a specific amount of catalyst prepared as described below. The catalyst was then pretreated as described in Tables 4 and 5 below, and the tubular reactor 132 was heated in an oven / furnace 134 at 250°C for at least 2 hours while flowing nitrogen at atmospheric pressure to reach the aforementioned temperature, and then the nitrogen flow was stopped. Oxygen or air was not allowed to enter reactor 112. After reaching the desired temperature, the reactants were metered into the tubular reactor 132 through the reactant inlet 130 at the desired pressure and flow rate for approximately 1 hour using a mass flow controller. Nitrogen was metered into the tube, and in some cases the contact time was adjusted. After this step, the reactants were passed through a DI water scrubber to remove HF and HCl. A 5% potassium hydroxide aqueous solution was also used to remove HF and HCl from the reaction, and no significant difference in the 1132 ratio in the product was observed. The reaction products were then collected in a cylinder cooled with dry ice, and subsequently in another cylinder cooled with liquid nitrogen. The products were analyzed by gas chromatography (GC), and the reaction selectivity and conversion rate were calculated.

[0126] Preparation of catalysts in Examples 11-54 (I) Preparation of fluorinated chromium oxide Fluorinated chromium oxide was obtained via the procedure disclosed in column 10, line 43 to column 12, line 39 of U.S. Patent No. 6,780,815 by Cerri et al. The fluorinated chromium oxide catalyst was 50 ml 2 It had a BET surface area of ​​211m / g. Before fluorination, the chromium oxide catalyst had a surface area of ​​211m 2 It had a surface area of ​​ / g.

[0127] (II) Preparation of fluorinated alumina 300 g of 3x5 mm alumina pellets in a 1-inch Inconel tubular reactor were slowly heated to 200°C under 1 L / min of N2, held at 200°C for 4 hours, and then increased to 300°C at a heating rate of 3°C / min. The catalyst was held at 300°C for 4 hours, and then increased to 400°C at a heating rate of 3°C / min and held for 8 hours.

[0128] Next, the catalyst was cooled to 200°C, and N2 was supplied at a pressure of 20 psig at a rate of 1 L / min to initiate the HF flow, which was supplied to the tubular reactor in a ratio of 1 wt% HF / N2 mixture. The supply rate was maintained at all points until the catalyst temperature was below 215°C, after which the HF / N2 ratio was increased to 2.5 wt%, 5 wt%, 9.6 wt%, 14 wt%, 21 wt%, and 25 wt%, with the HF / N2 ratio being increased to the next level only after the catalyst temperature had stabilized at all points or fallen below 215°C. After reaching an HF / N2 ratio of 25 wt%, the temperature of the tubular reactor was slowly raised to 350°C at a rate of 3°C / min, and this temperature was maintained for 2 hours while continuously supplying 25 wt% HF / N2 through the catalyst bed. Next, the temperature was increased to 400°C at a rate of 3°C / min and held at 25 wt% HF / N2 for 2 hours. Subsequently, the pressure was increased to 120 psig, the N2 flow was stopped, and the system was switched to 100 wt% HF at 120 psig and 1.5 lbs / h for 16 hours. Then, the HF supply was stopped, followed by the N2 flow being restarted at 6 L / min while cooling to room temperature.

[0129] (III) Preparation of 1% by weight Pd on fluorinated alumina (1% Pd on AlF3) In Examples 19-22, 1.25 g of Pd(NO3)2·2H2O was dissolved in 100 mL of DI water, and 50.0 g of AlF3 pellets (5 × 3 mm, Johnson Matthey) were added to the solution. The resulting mixture was immersed overnight at room temperature, and then the water was removed under vacuum. The resulting solid was further dried under vacuum at 150°C for 4 hours to obtain 36.6 g of pre-catalyst.

[0130] Next, the pre-catalyst was dried at 400°C for 4 hours under an airflow of 200 mL / min, and then reduced at 400°C for 2 hours using a hydrogen flow of 100 mL / min. The reduced catalyst was then used in the following dehydrofluorination reaction.

[0131] (IV) Preparation of fluorinated magnesium oxide In Examples 23-26, 300g of magnesium oxide chips (from MgO crystals) were placed in a 1-inch Inconel tube and treated in the same manner as the alumina fluoride described in (II) above.

[0132] (V) Preparation of 8.9 wt% Ni on fluorinated alumina (1% Ni on AlF3) In Examples 27-28, 8.9% Ni on alumina fluoride was similarly prepared using 24.7 g of Ni(NO3)2·6H2O dissolved in 100 mL of DI water, and 51.3 g of AlF3 pellets were added to the solution. The resulting solution was aged overnight, and then the water was removed under vacuum.

[0133] The obtained solid was further dried under vacuum at 150°C for 4 hours to obtain 51.5 g of a grayish solid. The pre-catalyst was further dried at 400°C for 4 hours under an air flow of 200 mL / min, and then reduced at 400°C for 2 hours using a H2 flow of 100 mL / min. The reduced catalyst was then used in the following dehydrofluorination reaction.

[0134] Table 4 below provides an overview of the reaction conditions.

[0135] [Table 4-1]

[0136] [Table 4-2]

[0137] [Table 4-3]

[0138] [Table 4-4]

[0139] The reactions in Table 4 yielded the product mixtures shown in Table 5 below.

[0140] [Table 5-1]

[0141] [Table 5-2]

[0142] [Table 5-3]

[0143] [Table 5-4]

[0144] [Table 5-5]

[0145] [Table 5-6]

[0146] [Table 5-7]

[0147] Examples 55-62 Hydrogenation of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to produce 1,1,2-trifluoroethane (HFC-143) Examples 1-5 and 10 described above were repeated at different temperatures, pressures, and contact times to determine the reactant ratios, and the results are summarized in Table 6 below.

[0148] [Table 6]

[0149] manner Embodiment 1 is a method for producing 1,1,2-trifluoroethane (HFC-143), comprising hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) by reaction with hydrogen in the presence of a catalyst to produce 1,1,2-trifluoroethane (HFC-143).

[0150] Embodiment 2 is the method according to Embodiment 1, wherein the catalyst is selected from the group consisting of palladium metal and platinum metal.

[0151] Embodiment 3 is the method according to Embodiment 1 or 2, wherein the catalyst is supported on a carrier selected from the group consisting of carbon and alumina.

[0152] Embodiment 4 is the method according to any one of Embodiments 1 to 3, wherein the catalyst is palladium supported on a carbon support.

[0153] Embodiment 5 is the method according to any one of Embodiments 1 to 4, wherein the catalyst is palladium supported on an alpha-alumina support.

[0154] Embodiment 6 is the method according to any one of Embodiments 1 to 5, wherein the catalyst is platinum supported on a carbon support.

[0155] Embodiment 7 is the method according to any one of Embodiments 1 to 6, wherein the catalyst is platinum supported on an alumina support.

[0156] Embodiment 8 is the method according to Embodiment 7, wherein the carrier is selected from alpha alumina, gamma alumina, delta alumina, and theta alumina.

[0157] Embodiment 9 is the method according to any one of Embodiments 1 to 8, wherein the hydrogenation process is carried out at a temperature of approximately 100°C to approximately 600°C.

[0158] Embodiment 10 is a method according to any one of Embodiments 1 to 9, wherein the hydrogenation process is carried out at a temperature of approximately 100°C to approximately 300°C.

[0159] Embodiment 11 is a method according to any one of Embodiments 1 to 10, wherein the hydrogenation process is carried out at a temperature of approximately 150°C to approximately 250°C.

[0160] Embodiment 12 is the method according to any one of Embodiments 1 to 11, wherein the hydrogenation process is carried out at a pressure of approximately 10 psig to approximately 100 psig.

[0161] Embodiment 13 is a method according to any one of Embodiments 1 to 12, wherein the hydrogenation step is carried out with a molar ratio of hydrogen to 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) of about 4:1 to about 10:1.

[0162] Embodiment 14 is a method according to any one of Embodiments 1 to 13, wherein the hydrogenation step achieves selectivity for at least 30% of 1,1,2-trifluoroethane (HFC-143).

[0163] Embodiment 15 is a method according to any one of Embodiments 1 to 14, wherein the hydrogenation step achieves a conversion rate of at least 30% of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143).

[0164] Embodiment 16 is a method according to any one of Embodiments 1 to 15, wherein the hydrogenation process is carried out with a contact time of approximately 1 second to approximately 60 seconds.

[0165] Embodiment 17 is the method according to any one of Embodiments 1 to 16, further comprising the additional step of defluorinating 1,1,2-trifluoroethane (HFC-143) in the presence of a catalyst to produce trans-1,2-difluoroethylene (HFO-1132E) and / or cis-1,2-difluoroethylene (HFO-1132Z).

[0166] Embodiment 18 is the method according to Embodiment 17, wherein the catalyst is selected from the group consisting of fluorinated chromium oxide, fluorinated aluminum oxide, fluorinated iron oxide, fluorinated magnesium oxide, chromium fluoride, alumina fluoride, iron fluoride, and magnesium fluoride.

[0167] Embodiment 19 is the method according to Embodiment 17 or 18, wherein the catalyst further comprises at least one of palladium and nickel supported on a carrier selected from fluorinated chromium oxide, fluorinated aluminum oxide, and fluorinated magnesium oxide.

[0168] Embodiment 20 is the method according to Embodiment 17, wherein the catalyst is fluorinated chromium oxide.

[0169] Embodiment 21 is the method according to Embodiment 17, wherein the catalyst is fluorinated aluminum oxide.

[0170] Embodiment 22 is the method according to Embodiment 17, wherein the catalyst is magnesium fluoride oxide.

[0171] Embodiment 23 is the method according to Embodiment 17, wherein the catalyst is palladium supported on fluorinated aluminum oxide.

[0172] Embodiment 24 is the method according to Embodiment 17, wherein the catalyst is nickel supported on fluorinated aluminum oxide.

[0173] Embodiment 25 is a method according to any one of Embodiments 17 to 24, wherein the dehydrofluorination process is carried out at a temperature of approximately 200°C to approximately 600°C.

[0174] Embodiment 26 is the method according to any one of claims 17 to 24, wherein the dehydrofluorination step is carried out under at least one of the following conditions: (i) a temperature of about 250°C to about 450°C, or (ii) a pressure of about 1 psig to about 50 psig.

[0175] Embodiment 27 is the method according to any one of claims 17 to 24, wherein the dehydrofluorination step is carried out under at least one of the following conditions: (i) in an inert atmosphere where the amount of oxygen is less than 0.05% by weight based on the total weight of the reactants in the reactor, or (ii) in an inert atmosphere where the amount of water is less than 0.05% by weight.

[0176] Embodiment 28 is the method according to any one of Embodiments 17 to 27, wherein the cis / trans molar ratio of the cis-1,2-difluoroethylene (HFO-1132Z) product to the trans-1,2-difluoroethylene (HFO-1132E) product is 2 to 15.

[0177] Embodiment 29 is a method according to any one of Embodiments 17 to 28, wherein the dehydrofluorination step achieves selectivity of about 80% to about 99% for trans-1,2-difluoroethylene (HFO-1132E) and cis-1,2-difluoroethylene (HFO-1132Z).

[0178] Embodiment 30 is a method according to any one of Embodiments 17 to 29, wherein the dehydrofluorination step achieves a conversion rate of approximately 50% to approximately 99% of 1,1,2-trifluoroethane (HFC-143) to trans-1,2-difluoroethylene (HFO-1132E) and cis-1,2-difluoroethylene (HFO-1132Z).

[0179] Embodiment 31 is a method according to any one of Embodiments 17 to 30, wherein the dehydrofluorination process is carried out with a contact time of approximately 1 second to approximately 60 seconds.

[0180] Embodiment 32 is the method according to any one of Embodiments 17 to 31, further comprising the additional step of isomerizing cis-1,2-difluoroethylene (HFO-1132Z) to produce trans-1,2-difluoroethylene (HFO-1132E).

[0181] Embodiment 33 is a composition produced from the method according to any one of Embodiments 17 to 32, comprising, based on the total weight of the composition, trans-1,2-difluoroethylene (HFO-1132E) present in an amount of at least 95% by weight and 1,1,1-trifluoroethane (HFC-143a) present in an amount of less than 5% by weight.

[0182] Embodiment 34 is the composition according to Embodiment 33, comprising, based on the total weight of the composition, trans-1,2-difluoroethylene (HFO-1132E) present in an amount of at least 97% by weight and 1,1,1-trifluoroethane (HFC-143a) present in an amount of less than 3% by weight.

[0183] Embodiment 35 is the composition according to Embodiment 34, comprising, based on the total weight of the composition, trans-1,2-difluoroethylene (HFO-1132E) present in an amount of at least 97% by weight and 1,1,1-trifluoroethane (HFC-143a) present in an amount of less than 3% by weight.

[0184] Embodiment 36 is a method for producing trans-1,2-difluoroethylene (HFO-1132E), comprising: hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) with hydrogen in the presence of a catalyst to produce 1,1,2-trifluoroethane (HFC-143); and dehydrofluorinating 1,1,2-trifluoroethane (HFC-143) in the presence of a catalyst to produce trans-1,2-difluoroethylene (HFO-1132E) and / or cis-1,2-difluoroethylene (HFO-1132Z).

[0185] Embodiment 37 is the method according to Embodiment 36, further comprising the additional step of isomerizing cis-1,2-difluoroethylene (HFO-1132Z) to produce trans-1,2-difluoroethylene (HFO-1132E).

[0186] Embodiment 38 is a method for producing 1,1,2-trifluoroethane (HFC-143), comprising hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) by reaction with hydrogen in the presence of a catalyst containing palladium or platinum to produce a product mixture, wherein the product mixture comprises, based on the total moles of organic components in the product mixture, at least 30 mol% of 1,1,2-trifluoroethane (HFC-143) and 0.1 mol% to 60 mol% of at least one of 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1-chloro-1,2,2-trifluoroethane (HCFC-133), 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123).

[0187] Embodiment 39 is the method according to Embodiment 38, wherein the product mixture further comprises at least one of the following, based on the total moles of organic components in the product mixture: 0.1 mol% to 10 mol% of 1,1-difluoroethane (HFC-152a), 0.1 mol% to 5 mol% of ethane (HC-170), 0.1 mol% to 3 mol% of chloroethane (HCC-160), 0.1 mol% to 3 mol% of 1-chloro-1,2-difluoroethane (HCFC-142a), and 0.1 mol% to 3 mol% of 1,1,1-trifluoroethane (HFC-143a).

[0188] Embodiment 40 is the method according to either Embodiment 38 or 39, wherein the catalyst is supported on a carrier selected from the group consisting of carbon and alumina.

[0189] Embodiment 41 is a method according to any one of Embodiments 38 to 40, wherein the hydrogenation process is carried out at a temperature of approximately 150°C to approximately 250°C.

[0190] Embodiment 42 is the method according to any one of Embodiments 38 to 41, wherein the hydrogenation process is carried out at a pressure of about 10 psig to about 100 psig.

[0191] Embodiment 43 is a method according to any one of Embodiments 38 to 42, wherein the hydrogenation step is carried out with a molar ratio of hydrogen to 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) of about 4:1 to about 10:1.

[0192] Embodiment 44 is a method according to any one of Embodiments 38 to 43, wherein the hydrogenation step achieves selectivity for at least 30% of 1,1,2-trifluoroethane (HFC-143).

[0193] Embodiment 45 is a method according to any one of Embodiments 38 to 44, wherein the hydrogenation step achieves selectivity for at least 70% of 1,1,2-trifluoroethane (HFC-143).

[0194] Embodiment 46 is a method according to any one of Embodiments 38 to 45, wherein the hydrogenation step achieves a combined selectivity of more than 75% for 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1-chloro-1,2,2-trifluoroethane (HCFC-133), 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123).

[0195] Embodiment 47 is a method according to any one of Embodiments 38 to 46, wherein the hydrogenation step achieves a combined selectivity of over 90% for 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1-chloro-1,2,2-trifluoroethane (HCFC-133), 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123).

[0196] Embodiment 48 is a method according to any one of Embodiments 38 to 47, wherein the hydrogenation step achieves a conversion rate of at least 75% of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143).

[0197] Embodiment 49 is a method according to any one of Embodiments 38 to 48, wherein the hydrogenation step achieves a conversion rate of at least 90% of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143).

[0198] Embodiment 50 is a method according to any one of Embodiments 38 to 49, wherein the hydrogenation step achieves selectivity of less than 10% for 1,1-difluoroethane (HFC-152a), ethane (HC-170), chloroethane (HCC-160), 1,1,1-trifluoroethane (HFC-143a), chlorodifluoroethane (1-chloro-2,2-difluoroethane (HCFC-142), 1-chloro-1,1-difluoroethane (HCFC-142b), and 1-chloro-1,2-difluoroethane (HCFC-142a), etc.).

[0199] Embodiment 51 is a method according to any one of Embodiments 38 to 50, wherein the hydrogenation process is carried out with a contact time of approximately 5 seconds to approximately 40 seconds.

[0200] Embodiment 52 is a method for producing trans-1,2-difluoroethylene (HFO-1132E), comprising defluorinating 1,1,2-trifluoroethane (HFC-143) in the presence of a catalyst selected from fluorinated alumina, palladium supported on fluorinated alumina, fluorinated magnesium oxide, and nickel supported on fluorinated alumina to produce a product mixture containing trans-1,2-difluoroethylene (HFO-1132E) and / or cis-1,2-difluoroethylene (HFO-1132Z).

[0201] Embodiment 53 is the method according to Embodiment 52, wherein the catalyst is alumina fluoride.

[0202] Embodiment 54 is the method according to either Embodiment 52 or 53, wherein the reactant mixture contains a cis / trans molar ratio of cis-1,2-difluoroethylene (HFO-1132Z) to trans-1,2-difluoroethylene (HFO-1132E) of 2 to 15.

[0203] Embodiment 55 is a method according to any one of Embodiments 52 to 54, wherein the dehydrofluorination step achieves selectivity of more than approximately 80% for trans-1,2-difluoroethylene (HFO-1132E) and cis-1,2-difluoroethylene (HFO-1132Z).

[0204] Embodiment 56 is the method according to any one of Embodiments 52 to 55, wherein the product of the dehydrofluoridation step contains less than 1 mol% of HFC-143a based on the total moles of organic components in the product mixture.

[0205] Embodiment 57 is a method according to any one of Embodiments 52 to 56, wherein a dehydrofluorination step is carried out, comprising at least one of the following conditions: (i) a temperature of about 300°C to about 400°C, (ii) a pressure of about 5 psig to about 30 psig, (iii) a contact time of about 1 second to about 60 seconds, (iv) an inert atmosphere in which the amount of oxygen present is less than 0.05% by weight based on the total weight of the reactants in the reactor, and (v) an inert atmosphere in which the amount of water present is less than 0.05% by weight based on the total weight of the reactants in the reactor.

Claims

1. A method for producing 1,1,2-trifluoroethane (HFC-143), The process includes hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) with hydrogen in the presence of a catalyst containing palladium or platinum to produce a product mixture, wherein the product mixture is Based on the total moles of organic components in the aforementioned product mixture, at least 30 mol% of 1,1,2-trifluoroethane (HFC-143) and A method comprising 0.1 mol% to 60 mol% of at least one of 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1-chloro-1,2,2-trifluoroethane (HCFC-133), 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123).

2. The product mixture is determined based on the total moles of organic components in the product mixture. 0.1 mol% to 10 mol% of 1,1-difluoroethane (HFC-152a), 0.1 mol% to 5 mol% ethane (HC-170), 0.1 mol% to 3 mol% chloroethane (HCC-160), 0.1 mol% to 3 mol% of 1-chloro-1,2-difluoroethane (HCFC-142a), and The method according to claim 1, further comprising at least one of 0.1 mol% to 3 mol% of 1,1,1-trifluoroethane (HFC-143a).

3. The method according to claim 1 or 2, wherein the catalyst is supported on a carrier selected from the group consisting of carbon and alumina.

4. The method according to any one of claims 1 to 3, wherein the hydrogenation step is carried out at a temperature of approximately 150°C to approximately 250°C.

5. The method according to any one of claims 1 to 4, wherein the hydrogenation step is carried out at a pressure of about 10 psig to about 100 psig.

6. The method according to any one of claims 1 to 5, wherein the hydrogenation step is carried out in a molar ratio of hydrogen to 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) of about 4:1 to about 10:

1.

7. The method according to any one of claims 1 to 6, wherein the hydrogenation step achieves selectivity for at least 30% of 1,1,2-trifluoroethane (HFC-143).

8. The method according to any one of claims 1 to 7, wherein the hydrogenation step achieves selectivity for at least 70% of 1,1,2-trifluoroethane (HFC-143).

9. The method according to any one of claims 1 to 8, wherein the hydrogenation step achieves a combined selectivity of more than 75% for 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1-chloro-1,2,2-trifluoroethane (HCFC-133), 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123).

10. The method according to any one of claims 1 to 9, wherein the hydrogenation step achieves a combined selectivity of more than 90% for 1,1,2-trifluoroethane (HFC-143), 1-chloro-1,1,2-trifluoroethane (HCFC-133b), 1-chloro-1,2,2-trifluoroethane (HCFC-133), 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a), and trifluoroethylene (HFO-1123).

11. The method according to any one of claims 1 to 10, wherein the hydrogenation step achieves a conversion rate of at least 75% of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143).

12. The method according to any one of claims 1 to 11, wherein the hydrogenation step achieves a conversion rate of at least 90% of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to 1,1,2-trifluoroethane (HFC-143).

13. The method according to any one of claims 1 to 12, wherein the hydrogenation step achieves selectivity of less than 10% for 1,1-difluoroethane (HFC-152a), ethane (HC-170), chloroethane (HCC-160), 1,1,1-trifluoroethane (HFC-143a), chlorodifluoroethane (1-chloro-2,2-difluoroethane (HCFC-142), 1-chloro-1,1-difluoroethane (HCFC-142b), and 1-chloro-1,2-difluoroethane (HCFC-142a), etc.).

14. The method according to any one of claims 1 to 13, wherein the hydrogenation step is carried out with a contact time of about 5 seconds to about 40 seconds.

15. A method for producing trans-1,2-difluoroethylene (HFO-1132E), A method comprising defluoridating 1,1,2-trifluoroethane (HFC-143) in the presence of a catalyst selected from fluorinated alumina, palladium supported on fluorinated alumina, fluorinated magnesium oxide, and nickel supported on fluorinated alumina to produce a product mixture containing trans-1,2-difluoroethylene (HFO-1132E) and / or cis-1,2-difluoroethylene (HFO-1132Z).

16. The method according to claim 15, wherein the catalyst is alumina fluoride.

17. The method according to claim 15 or 16, wherein the product mixture contains 2 to 15 cis / trans molar ratios of cis-1,2-difluoroethylene (HFO-1132Z) to trans-1,2-difluoroethylene (HFO-1132E).

18. The method according to any one of claims 15 to 17, wherein the defluoridation step achieves selectivity of more than approximately 80% for trans-1,2-difluoroethylene (HFO-1132E) and cis-1,2-difluoroethylene (HFO-1132Z).

19. The method according to any one of claims 15 to 18, wherein the product mixture contains less than 1 mol% of HFC-143a based on the total moles of organic components in the product mixture.

20. The aforementioned dehydrofluoride treatment process is carried out under the following conditions: (i) A temperature of approximately 300°C to approximately 400°C, (ii) Pressure of approximately 5 psig to approximately 30 psig, (iii) Contact time of approximately 1 second to approximately 60 seconds, (iv) an inert atmosphere in which the amount of oxygen present is less than 0.05% by weight, based on the total weight of the reactants in the reactor, and (v) The method according to any one of claims 15 to 19, wherein the dehydrofluorination step is carried out in an inert atmosphere, the amount of water present being less than 0.05% by weight, based on the total weight of the reactants in the reactor, and the method according to any one of claims 15 to 19.

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