Azeotropic properties and azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143), and their uses.

Abstract

An azeotropic or azeotropic-like composition essentially consisting of effective amounts of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143). Methods for separating the azeotropic or azeotropic-like composition and / or utilizing the composition in extraction and pressure swing distillation are also disclosed in connection with a method for producing 1,1,2-trifluoroethane (HFC-143).

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application No. 63 / 465,138, filed May 9, 2023, entitled "AZEOTROPE AND AZEOTROPE - LIKE COMPOSITIONS OF 1,1,2 - TRICHLORO - 1,2,2 - TRIFLUOROETHANE (CFC - 113) AND 1,1,2 - TRIFLUOROETHANE (HFC - 143) AND APPLICATIONS THEREOF", and claims priority to U.S. Patent Application No. 18 / 658,326, filed May 8, 2024, both of which are hereby incorporated by reference in their entirety.

[0002] (Field of the Invention) The present disclosure relates to azeotropic and azeotrope - like compositions, particularly azeotropic and azeotrope - like compositions consisting essentially of 1,1,2 - trichloro - 1,2,2 - trifluoroethane (CFC - 113) and 1,1,2 - trifluoroethane (HFC - 143), and to the uses or applications of these compositions.

Background Art

[0003] Fluorocarbon fluids have desirable properties for use as heat transfer media, immersion coolants, liquid or gaseous dielectrics, industrial refrigerants, and other applications.

[0004] For example, 1,2-difluoroethylene (HFO-1132) has recently been found to have increasing utility for a variety of uses. 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 proportions. 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. Improved methods for producing HFO-1132, particularly HFO-1132E, are desired.

[0005] Azeotropic and azeotropic-like compositions may be encountered during the production of fluorocarbon fluids, and understanding any such azeotropic or azeotropic-like composition can help improve the efficiency of the production process. [Overview of the project]

[0006] This disclosure provides homogeneous azeotropic or azeotropic-like compositions with minimum boiling points, essentially comprising 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143), as well as uses or applications of these compositions.

[0007] In one embodiment, the present disclosure provides an azeotropic or azeotropic-like composition essentially consisting of effective amounts of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143).

[0008] In another form, 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) with hydrogen (H2) to form a product mixture comprising an azeotropic or azeotropic-like composition essentially consisting of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143); and separating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) from 1,1,2-trifluoroethane (HFC-143) to provide a product composition comprising 1,1,2-trifluoroethane (HFC-143). The separation may be carried out by extraction or pressure swing distillation. [Brief explanation of the drawing]

[0009] [Figure 1] This is a process flow diagram for separating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143). [Figure 2] This graph shows the everiometer measurements of azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) at 14.7 psia. [Figure 3] This is a schematic diagram of an apparatus for separating azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) by pressure swing distillation. [Figure 4] This is a schematic diagram of an apparatus for separating azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) by extractive distillation. [Modes for carrying out the invention]

[0010] This disclosure provides homogeneous minimum boiling point azeotropic or azeotropic-like compositions essentially consisting of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), also referred to herein as R113, and 1,1,2-trifluoroethane (HFC-143, also referred to herein as R143), as well as uses or applications of these compositions.

[0011] I. Description of azeotropic or azeotropic compositions An "azeotropic" composition is a specific combination of two or more components. Azeotropic compositions can be characterized in various ways. For example, at a given pressure, an azeotropic composition boils either at a constant characteristic temperature higher than the component with the higher boiling point (maximum boiling point azeotrope) or at a constant characteristic temperature lower than the component with the lower boiling point (minimum boiling point azeotrope). At this characteristic temperature, the same composition exists in both the gas and liquid phases. Azeotropic compositions do not separate during boiling or evaporation. Therefore, the components of an azeotropic composition cannot be separated during phase transition.

[0012] Azeotropic compositions are also characterized in that, at their characteristic azeotropic temperature, the boiling point pressure of the liquid phase (bubble point pressure) is the same as the dew point pressure of the vapor phase.

[0013] The behavior of azeotropic compositions is in contrast to that of non-azeotropic compositions, where the liquid composition changes to a considerable extent during boiling or evaporation.

[0014] For the purposes of this disclosure, an azeotropic composition is characterized as a composition that boils at a constant characteristic temperature lower than the boiling points of two or more components (a minimum boiling point azeotrope), thereby having the same composition in both the gas and liquid phases.

[0015] However, those skilled in the art will understand that at different pressures, both the composition and boiling point of an azeotropic composition will change to some extent. Therefore, depending on the temperature and / or pressure, an azeotropic composition may have a variable composition. Thus, those skilled in the art will understand that an azeotropic composition can be defined using a compositional range rather than a fixed composition. Furthermore, an azeotrope can also be defined in terms of the precise weight percentage of each component of a composition characterized by a fixed boiling point at a particular pressure.

[0016] An "azeotropic" composition is a composition of two or more components that behave substantially as an azeotropic composition. Therefore, for the purposes of this disclosure, an azeotropic composition is a combination of two or more different components that boil at substantially a constant temperature when in liquid form under a given pressure and provide a vapor composition substantially identical to that of the boiling liquid composition.

[0017] Azeotropic or azeotropic-like compositions can be identified using a number of different methods.

[0018] For the purposes of this disclosure, azeotropic or azeotropic-like compositions are identified experimentally using an everiometer (Walas, Phase Equilibria in Chemical Engineering, Butterworth-Heinemann, 1985, 533-544). An everiometer is designed to provide extremely accurate measurements of the boiling point of a liquid by measuring the vapor-liquid equilibrium temperature.

[0019] The boiling point of each individual component is measured at a constant pressure. As will be understood by those skilled in the art, for two-component azeotropic or azeotropic-like compositions, the boiling point of one of the components of the composition is measured first. Then, the second component of the composition is added in varying amounts, and the boiling point of each component of the resulting composition is measured using an everiometer at the same constant pressure.

[0020] The measured boiling points are plotted against the composition of the tested composition, for example in the case of a binary azeotrope, against the amount of the second component added to the composition (expressed either as weight % or mole %). The presence of an azeotropic composition can be identified by observing a maximum or minimum boiling temperature that is higher or lower than the boiling point of either of the individual components.

[0021] As will be understood by those skilled in the art, the identification of an azeotropic or azeotrope-like composition is done by comparing the change in the boiling point of the composition upon addition of the second component to the first component with the boiling point of the first component. Thus, there is no need to calibrate the system to the reported boiling points of the specific components in order to measure the change in boiling point.

[0022] As used herein, with respect to the components of an azeotropic or azeotrope-like composition or mixture, the term "consisting essentially of" means that the composition may contain additional components, provided that the composition contains the indicated components in an azeotropic or azeotrope-like ratio and that the additional components do not form a new azeotropic or azeotrope-like system. For example, an azeotropic mixture consisting essentially of two compounds forms a binary azeotrope and may optionally contain one or more additional components, provided that the additional components do not make the mixture non-azeotropic and do not form an azeotrope with either or both of the compounds (e.g., do not form azeotropes of three or more components).

[0023] As used herein, the term "about", when used in connection with the recited weight percentages of the components of the present composition, includes a deviation of ±0.3% from the recited weight percentage.

[0024] As used herein, the singular forms "a", "an", and "the" include the plural forms unless the context clearly dictates otherwise. Further, when a quantity, concentration, or other value or parameter is given as either a range, a preferred range, or an enumeration of upper preferred values and lower preferred values, this is to be understood as specifically disclosing any and all ranges formed from any pair of any upper range limit or upper preferred value and any lower range limit or lower preferred value, whether or not the ranges or values are separately disclosed. Where numerical ranges are recited herein, unless otherwise stated, the range is intended to include its endpoints and all integers and fractions within the range. The scope of the present disclosure is not intended to be limited to the specific values recited when defining the range.

[0025] As described above, in the case of an azeotrope, at the maximum boiling point or the minimum boiling point, the composition of the vapor phase is the same as that of the liquid phase. Thus, an azeotrope-like composition is a composition of components that provides a substantially constant minimum boiling point or maximum boiling point, and at that substantially constant boiling point, the composition of the vapor phase is substantially the same as that of the liquid phase.

[0026] II. Azeotropy and Azeotrope-Like Compositions of 1,1,2-Trichloro-1,2,2-Trifluoroethane (CFC-113) and 1,1,2-Trifluoroethane (HFC-143) The present disclosure provides a homogeneous azeotropic or azeotrope-like composition having a minimum boiling point, comprising effective amounts of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143). In particular, the present disclosure provides a homogeneous azeotropic or azeotrope-like composition having a minimum boiling point consisting essentially of effective amounts of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143). The present disclosure provides a homogeneous azeotropic or azeotrope-like composition having a minimum boiling point consisting of effective amounts of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143).

[0027] The azeotropic or azeotropic composition may contain approximately 12.0% to 1.1% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and approximately 88.0% to 98.9% by weight of 1,1,2-trifluoroethane (HFC-143) at a temperature of approximately 3.7°C to approximately 79.7°C and a pressure of approximately 14.7 psia to approximately 165.2 psia. Azeotropic or azeotropic compositions may essentially consist of about 12.0% to about 1.1% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and about 88.0% to about 98.9% by weight of 1,1,2-trifluoroethane (HFC-143) at a temperature of about 3.7°C to about 79.7°C and a pressure of about 14.7 psia to about 165.2 psia. Azeotropic or azeotropic compositions may consist of approximately 12.0% to 1.1% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and approximately 88.0% to 98.9% by weight of 1,1,2-trifluoroethane (HFC-143) at a temperature of approximately 3.7°C to approximately 79.7°C and a pressure of approximately 14.7 psia to approximately 165.2 psia.

[0028] The azeotropic or azeotropic composition, at a pressure of about 14.7 psia, consists of about 77.6% to about 99.9% by weight of 1,1,2-trifluoroethane (HFC-143) and about 0.1% to about 22.4% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), more specifically, about 83.7% to about 96.1% by weight of 1,1,2-trifluoroethane (HFC-143) and about 3.9% to about 16.3% by weight of 1,1,2-trichloro-1,2,2-trichloroethane at a pressure of about 14.7 psia. It may contain fluoroethane (CFC-113), more specifically about 85.8% to 94.8% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and about 5.2% to 14.2% by weight of 1,1,2-trifluoroethane (HFC-143), and even more specifically about 88% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and about 12% by weight of 1,1,2-trifluoroethane (HFC-143).

[0029] The azeotropic or azeotropic composition, at a pressure of about 14.7 psia, consists of about 77.6% to 99.9% by weight of 1,1,2-trifluoroethane (HFC-143) and about 0.1% to 22.4% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), more specifically, about 83.7% to 96.1% by weight of 1,1,2-trifluoroethane (HFC-143) and about 3.9% to 16.3% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane. It can essentially consist of oleethane (CFC-113), more specifically, about 85.8% to about 94.8% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and about 5.2% to about 14.2% by weight of 1,1,2-trifluoroethane (HFC-143), and even more specifically, about 88% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and about 12% by weight of 1,1,2-trifluoroethane (HFC-143).

[0030] The azeotropic or azeotropic composition, at a pressure of about 14.7 psia, consists of about 77.6% to about 99.9% by weight of 1,1,2-trifluoroethane (HFC-143) and about 0.1% to about 22.4% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), more specifically, about 83.7% to about 96.1% by weight of 1,1,2-trifluoroethane (HFC-143) and about 3.9% to about 16.3% by weight of 1,1,2-trichloro-1,2,2-trichloroethane at a pressure of about 14.7 psia. Fluoroethane (CFC-113), more specifically, it may consist of approximately 85.8% to 94.8% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and approximately 5.2% to 14.2% by weight of 1,1,2-trifluoroethane (HFC-143), and even more specifically, approximately 88% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and approximately 12% by weight of 1,1,2-trifluoroethane (HFC-143).

[0031] In other words, the composition may contain 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) in amounts of about 22.4% by weight, about 16.3% by weight, or about 14.2% by weight, or about 12% by weight, based on the total weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) in azeotropic or azeotropic compositions at a pressure of about 14.7 psia, in large amounts of about 22.4% by weight, about 16.3% by weight, or about 14.2% by weight, or about 0.1% by weight, or any two of the above values ​​as endpoints, for example, about 0.1% by weight to about 22.4% by weight, about 3.9% by weight to about 16.3% by weight, about 5.2% by weight to about 14.2% by weight, and / or about 12% by weight.

[0032] In other words, the composition may consist essentially of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) at a pressure of about 14.7 psia, based on the total weight of azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143), in amounts of about 22.4% by weight, about 16.3% by weight, or about 14.2% by weight, or about 12% by weight, or in amounts of about 5.2% by weight, about 3.9% by weight, or about 0.1% by weight, or any two of the above values ​​as endpoints, for example, about 0.1% by weight to about 22.4% by weight, about 3.9% by weight to about 16.3% by weight, about 5.2% by weight to about 14.2% by weight, and / or about 12% by weight.

[0033] In other words, the composition may consist of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) in amounts of about 22.4% by weight, about 16.3% by weight, or about 14.2% by weight, or about 12% by weight, based on the total weight of azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) at a pressure of about 14.7 psia, in amounts of about 22.4% by weight, about 16.3% by weight, or about 14.2% by weight, or about 0.1% by weight, or any two of the above values ​​as endpoints, for example, about 0.1% by weight to about 22.4% by weight, about 3.9% by weight to about 16.3% by weight, about 5.2% by weight to about 14.2% by weight, and / or about 12% by weight.

[0034] In other words, the composition may contain 1,1,2-trifluoroethane (HFC-143) in amounts of about 99.9% by weight, about 96.1% by weight, or about 94.8% by weight, or about 88.0% by weight, based on the total weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) in an azeotropic or azeotropic composition at a pressure of about 14.7 psia, or in a large amount of about 99.9% by weight, about 96.1% by weight, or about 94.8% by weight, or about 88.0% by weight, or in a small amount of about 85.8% by weight, about 83.7% by weight, or about 77.6% by weight, or any two of the above values ​​as endpoints, for example, about 77.6% by weight to about 99.9% by weight, about 83.7% by weight to about 96.1% by weight, about 85.8% by weight to about 94.8% by weight, and / or about 88.0% by weight.

[0035] In other words, the composition may consist essentially of 1,1,2-trifluoroethane (HFC-143) at a pressure of about 14.7 psia, based on the total weight of azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143), in amounts of about 99.9% by weight, about 96.1% by weight, about 94.8% by weight, or about 88.0% by weight, or in amounts of about 85.8% by weight, about 83.7% by weight, or about 77.6% by weight, or in amounts of any two of the above values ​​as endpoints, for example, about 77.6% by weight to about 99.9% by weight, about 83.7% by weight to about 96.1% by weight, about 85.8% by weight to about 94.8% by weight, and / or about 88.0% by weight.

[0036] In other words, the composition may consist of 1,1,2-trifluoroethane (HFC-143) in amounts of about 99.9% by weight, about 96.1% by weight, about 94.8% by weight, or about 88.0% by weight, based on the total weight of azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) at a pressure of about 14.7 psia, in large amounts of about 99.9% by weight, about 96.1% by weight, about 94.8% by weight, or about 88.0% by weight, or in small amounts of about 85.8% by weight, about 83.7% by weight, or about 77.6% by weight, or any two of the above values ​​as endpoints, for example, about 77.6% by weight to about 99.9% by weight, about 83.7% by weight to about 96.1% by weight, about 85.8% by weight to about 94.8% by weight, and / or about 88.0% by weight.

[0037] The composition may have azeotropic or azeotropic-like characteristics at temperatures within a range encompassed by any two of the above values ​​as endpoints, such as approximately 3.7°C, approximately 19.6°C, approximately 29.5°C, approximately 39.5°C, approximately 49.4°C, approximately 59.1°C, approximately 69.9°C, and / or approximately 79.7°C.

[0038] The composition may have azeotropic or azeotropic-like characteristics at pressures of approximately 14.7 psia, approximately 27.7 psia, approximately 39.4 psia, approximately 54.6 psia, approximately 73.8 psia, 97.3 psia, approximately 129.3 psia, and / or approximately 165.2 psia, or within any range encompassed by any two of the above values ​​as endpoints, such as approximately 14.7 psia to approximately 165.2 psia.

[0039] Specifically, as shown in Table 1 below, the azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) can correlate with pressure (psia) and saturation temperature.

[0040] In column (i) of Table 1 below, temperature glide is the difference between the saturated vapor temperature and the saturated liquid temperature at a fixed pressure in thermodynamic equilibrium. Therefore, azeotropic compositions have a temperature glide of zero, and azeotropic-like compositions may have a temperature glide that is substantially close to zero. A temperature glide of less than 0.5°C is substantially close to zero, and therefore compositions that satisfy such a temperature glide are identified as azeotropic-like. Using this method, the relative compositions in column (i) of Table 1 below, which can be considered to represent the broadest azeotropic-like composition range, were determined.

[0041] In column (ii) of Table 1 below, relative volatility is defined as the ratio of the vapor composition to the liquid composition of the most volatile component at a fixed pressure in thermodynamic equilibrium, compared to the ratio of the vapor composition to the liquid composition of the less volatile component. Therefore, azeotropic compositions have a relative volatility of 1.0, and azeotropic-like compositions have a relative volatility substantially close to 1.0. A relative volatility of 1.1 is substantially close to 1.0, and therefore, compositions satisfying such a relative volatility were identified as azeotropic-like. Using this method, the relative compositions in column (ii) of Table 1 below, which can be considered to be in the intermediate azeotropic-like composition range, were determined.

[0042] In column (iii) of Table 1 below, a relative volatility of 1.05 is substantially close to 1.0, and therefore, compositions satisfying such relative volatility are considered azeotropic. This can be considered the narrowest range of azeotropic mixture-like compositions.

[0043] Column (1) of Table 1 below lists azeotropic compositions (minimal boiling point azeotropes) that, at a given pressure, boil at a specific characteristic temperature lower than that of components with lower boiling points. At this characteristic temperature, the same composition exists in both the gas and liquid phases. Therefore, the components of the azeotropic composition cannot be separated during the phase change and are considered an azeotropic composition. Such compositional values ​​are shown in Column (1) of Table 1 below, corresponding to each pressure and saturation temperature.

[0044] Therefore, and from the above viewpoint, azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) may contain any of the values ​​listed in each of the columns (1), (i), (ii), or (iii) of each row in Table 1 below.

[0045] In another embodiment, azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) may essentially consist of any of the values ​​listed in each of the columns (1), (i), (ii), or (iii) of each row in Table 1 below.

[0046] In further embodiments, azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) may consist of any of the values ​​listed in each of the columns (1), (i), (ii), or (iii) of each row in Table 1 below.

[0047] [Table 1]

[0048] III. Formation of E-1,2-difluoroethylene (HFO-1132E) It has been found that azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) may be formed during the production of E-1,2-difluoroethylene (HFO-1132E) or otherwise encountered.

[0049] In particular, azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) may be formed in or otherwise encountered in 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 scheme or process ("Scheme 1").

[0050] Scheme 1 comprises the following three steps: (i) hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to produce 1,1,2-trifluoroethane (HFC-143); (ii) dehydrofluorinating 1,1,2-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).

[0051] The following are schematic formulas for the three steps of Scheme 1. Scheme 1 (i)CFCl2-CF2Cl(CFC-113)+H2→CFH2-CF2H(HFC-143)+HCl (ii) CFH2 - CF2H (HFC-143) → Trans-CFH = CHF (HFO-1132E) + Cis-CFH = CFH (HFO-1132Z) + HF (iii) cis-CFH=CFH(HFO-1132Z) → trans-CFH=CHF(HFO-1132E)

[0052] 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).

[0053] The azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) are formed in step (i) of Scheme 1 above. Here, 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) may be considered a desirable intermediate, and the separation of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and subsequent recirculation to the hydrogenation process in step (i) can improve the overall recovery of the 1,1,2-trifluoroethane (HFC-143) product. Therefore, it may be important to use or utilize such azeotropic or azeotropic compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) to improve the operation of Scheme 1 and produce E-1,2-difluoroethylene (HFO-1132E) in a desired amount or purity. For example, by separating such azeotropic or azeotropic compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143), the recovery purity of 1,1,2-trifluoroethane (HFC-143) can be increased by substantially removing 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) from 1,1,2-trifluoroethane (HFC-143). Furthermore, since 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) is itself a reagent in step (i) of scheme 1, 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) may be recycled back into the reaction in step (i), thus reducing the amount of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) required in step (i).

[0054] The present disclosure further relates to a method for producing 1,1,2-trifluoroethane (HFC-143), comprising: hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) with hydrogen (H2) to form a product mixture, wherein the product mixture comprises an azeotropic or azeotropic-like composition essentially consisting of an effective amount of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143); and separating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) to provide a product composition containing 1,1,2-trifluoroethane (HFC-143). The azeotropic or azeotropic-like compositions provided by this method essentially consist of effective amounts of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143), as defined in the above disclosure.

[0055] The method may further include recirculating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to the hydrogenation step. The separation step may include transporting the product mixture to a first column having a first pressure; collecting a first bottom product from the first column; and transporting the first distillate from the first column to a second column having a second pressure to provide a second distillate and a second bottom product, wherein the second distillate contains an azeotropic or azeotropic composition; and collecting a second bottom product from the second column. The pressure in the first column may be lower than the pressure in the second column, in which case the bottom product of the first column will essentially consist of 1,1,2-trifluoroethane (HFC-143) and the bottom product of the second column will essentially consist of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113). Alternatively, the pressure in the first column may be higher than the pressure in the second column, in which case the bottom product of the first column will essentially consist of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and the bottom product of the second column will essentially consist of 1,1,2-trifluoroethane (HFC-143). The separation step may include an additional step of recycling the second distillate back into the first column.

[0056] Alternatively, the separation step may include transporting the product mixture and the adjunct fluid to a first column; collecting a first distillate from the first column containing a first component of the azeotropic or azeotropic-like composition; collecting a first bottom product from the first column containing a mixture of the adjunct and a second component of the azeotropic or azeotropic composition; transporting the first bottom product to a second column to separate the adjunct from the second component of the azeotropic or azeotropic composition; and removing a composition essentially consisting of the second component of the azeotropic or azeotropic composition as a second distillate from the second column. The first component of the azeotropic or azeotropic composition may consist of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), and the second component of the azeotropic or azeotropic composition consists of 1,1,2-trifluoroethane (HFC-143). Alternatively, the first component of the azeotropic or azeotropic-like composition may consist of 1,1,2-trifluoroethane (HFC-143), and the second component of the azeotropic or azeotropic-like composition may consist of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113). The separation step may include an additional step of recirculating the second column bottom product, which is essentially composed of the adjunct, from the second column to the first column.

[0057] It will be understood that step (i) of Scheme 1 disclosed above with respect to the production of HFO-1132E discloses a method for producing HFC-143. Therefore, all features disclosed with respect to step (i) of Scheme 1 below also apply to a method for producing HFC-143.

[0058] For example, as shown in Figure 1, the inlet flow 110 to process 100 containing at least the reactant from step (i): CFCl2-CF2Cl(CFC-113)+H2 may be mixed with the recirculation flow 116 (as described in further detail herein) to form a reactant flow 112. After mixing, the reactant flow 112 may be sent to the first unit operation 105.

[0059] The first unit operation 105 may be a hydrogenation reactor, in which step (i) of scheme 1 is carried out to produce 1,1,2-trifluoroethane (HFC-143). Here, the first unit operation 105 may be 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. The hydrogenation reaction of step (i) may be carried out in the gas phase or vapor phase, and the reactor may be first cleaned by flowing an inert gas such as nitrogen, followed by loading with a catalyst. The catalyst may include metals such as palladium, platinum, rhodium, ruthenium, iron, cobalt, or nickel. More specifically, the catalyst may include palladium metal, platinum metal, or a combination of palladium metal and platinum metal. The catalyst can be supported on a suitable support such as carbon or alumina. For example, the catalyst may be palladium on a carbon support, platinum on a carbon support, and / or palladium or platinum on an alumina support.

[0060] The reagent stream 112 flows through the catalyst bed in the first unit operation 105 (for example, either upward or downward) and undergoes the hydrogenation reaction of step (i) of scheme 1. Here, 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 within any range encompassed by any two of the aforementioned values ​​as 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 350°C, more preferably about 200°C to about 300°C. 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, and may be within any approximate range or range encompassed by the two aforementioned values ​​as endpoints. For example, the contact time may preferably be from about 1 second to about 120 seconds. 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 may be 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 may be within any range encompassed by the two aforementioned values ​​as endpoints. For example, the pressure may preferably be about 10 psig to about 300 psig.

[0061] After the reaction, the reagent stream 112 forms a product stream 114 containing one or a combination of HCl, 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), 1,1,2-trifluoroethane (HFC-143), and azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143). As described above, 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) may be considered a desirable intermediate. Therefore, the separation of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) from 1,1,2-trifluoroethane (HFC-143), and the subsequent recirculation of 1,2-trichloro-1,2,2-trifluoroethane (CFC-113) into reagent stream 112 may be desirable to enhance the recovery of 1,1,2-trifluoroethane (HFC-143). The recovery of 1,1,2-trifluoroethane (HFC-143) enhances the production of E-1,2-difluoroethylene (HFO-1132E).

[0062] Specifically, upon exiting the first unit operation 105, the product stream 114 may enter the second unit operation 107. The second unit operation 107 may separate the components of the azeotropic or azeotropic-like composition of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) from each other by means of, for example, pressure swing distillation, extractive distillation, permeation vaporization, adsorption, such as pressure swing adsorption, membrane separation, etc. Pressure swing distillation is described in more detail specifically in Section IV, and extractive distillation is described in more detail specifically in Section V, both of which are provided herein.

[0063] After separation, HCl and 1,1,2-trifluoroethane (HFC-143) are recovered in recovery stream 118, and the desired intermediate of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) is recycled back to process 100 as recirculation stream 116. Specifically, the amount or purity of 1,1,2-trifluoroethane (HFC-143) in recovery stream 118 may be, for example, greater than 90 mol%, greater than 95 mol%, greater than 97 mol%, greater than 99 mol%, or greater than 99.5 mol%, based on the total number of moles of organic components in the composition. The amount of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) in the recovered stream 118 may be less than 5000 ppm, less than 3000 ppm, less than 2000 ppm, less than 1000 ppm, less than 500 ppm, or less than 250 ppm, for example, based on the total number of moles of organic components in the composition.

[0064] As described above, the recirculation stream 116, which contains substantially all of the 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), may be mixed with the inlet stream 110 when forming the reagent stream 112. Here, the separated and recirculated 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) may be added along with the components of the inlet stream 110 to reduce the amount of replenishment 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) required for the reaction process, and thus improve the operation of Scheme 1. Although not shown, the recovery stream 118 may then be sent to further unit operations to separate HCl from 1,1,2-trifluoroethane (HFC-143), and the unit operations may be one or a combination thereof, such as an absorption unit, an adsorption unit, a membrane separator, a cryogenic separator, a subsequent chemical reactor, or a distillation unit. After removing HCl from 1,1,2-trifluoroethane (HFC-143), 1,1,2-trifluoroethane (HFC-143) may be used as the reactant in step (ii).

[0065] IV. Separation of azeotropic and azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) by pressure swing distillation This disclosure provides a method for separating azeotropic and azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) by pressure swing distillation, as discussed below and in Example 3.

[0066] In the first step, a mixture of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) is transported to a first low-pressure column having a first pressure to obtain a first distillate and a first bottom product. The first bottom product is a concentrated stream of 1,1,2-trifluoroethane (HFC-143) collected from the bottom of the low-pressure column. The first distillate is an azeotropic or azeotropic-like composition of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143), which is collected from the top of the low-pressure column and transported to a second high-pressure column to obtain a second distillate from the top of the high-pressure column and a second bottom product from the bottom of the high-pressure column. The second bottom product is a concentrated stream of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), collected from the high-pressure column. The second distillate contains an azeotropic or azeotropic-like composition essentially consisting of effective amounts of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143), which may be recirculated back to the low-pressure column.

[0067] The above process may be modified to reverse the order of the low-pressure and high-pressure columns, in which case the high-pressure column is the first column and the low-pressure column is the second column. When modified in this way, the bottom product of the first column is a concentrated flow of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), and the bottom flow of the second column is a concentrated flow of 1,1,2-trifluoroethane (HFC-143).

[0068] A schematic diagram of an exemplary separation apparatus is shown in Figure 3. Referring to this figure, a mixture of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) is fed as feed stream 10 to a first low-pressure column 12. The low-pressure column 12 yields a first distillate stream 14 which is an azeotropic or azeotropic-like composition of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143), and a first bottom product 16 which may be concentrated with HFC-143 or may essentially consist of HFC-143. The first distillate flow 14 is then transported to the high-pressure column 18 to obtain a second distillate flow 22, which is an azeotropic or azeotropic-like composition of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143), and a second bottom product 20. The second bottom product 20 is either concentrated with CFC-113 or essentially consists of HCFC-142B. The second distillate flow 22 may optionally be returned to the feed flow 10, thereby being recycled to the low-pressure column 12.

[0069] According to this method, if an azeotropic or azeotropic-like composition of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) is formed, for example, during the formation of E-1,2-dichloroethane (HFO-1132E) according to Scheme 1, for example, during step (i) of Scheme 1 during the formation of 1,1,2-trifluoroethane (HFC-143), then 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) is formed according to Scheme 1. The azeotropic or azeotropic-like composition of difluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) may be separated into its constituent components, the 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) component and the 1,1,2-trifluoroethane (HFC-143) component, which may then be recycled back to an appropriate location in the production process and / or recovered as the final product.

[0070] V. Separation of azeotropic and azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) by extractive distillation. This disclosure provides a method for separating azeotropic and azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) by extractive distillation. Example 4 considers one such embodiment. A schematic diagram of an exemplary separation apparatus is shown in Figure 4.

[0071] For example, the extractive distillation method may include transporting the product mixture and the adjunct fluid to a first column. The extractive distillation method may further include collecting the first distillate from the first column containing the first component of the azeotropic or azeotropic-like composition. The extractive distillation method may further include collecting the bottom product of the first column from the first column containing a mixture of the adjunct and the second component of the azeotropic or azeotropic-like composition. The extractive distillation method may further include transporting the bottom product of the first column to a second column to separate the adjunct from the second component of the azeotropic or azeotropic-like composition. The extractive distillation method may further include removing the composition essentially consisting of the second component of the azeotropic or azeotropic-like composition from the second column as a second distillate.

[0072] A schematic diagram of an exemplary separation apparatus is shown in Figure 4. Referring to this figure, a product stream 24 (which may be the same as product stream 114, referring to Figure 1) containing at least an azeotropic or azeotropic-like composition of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) is transported to the extraction column 26 together with an adjuvant fluid 28. The adjuvant fluid 28 is a composition in which one of the components of the azeotropic or azeotropic-like composition of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) has a higher affinity for the adjuvant fluid compared to the other component. Here, one of the components of the azeotropic or azeotropic-like composition dissolves more readily in the adjuvant fluid 28 than the other component. Therefore, the azeotropic fluid 28 may be used to "decompose" the azeotropic or azeotropic-like composition into its individual components based on the difference in affinity / solubility, and thus this may be used to selectively separate each component of the azeotropic or azeotropic-like composition. For example, the conjugate fluid 28 may have a higher affinity for 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and may act as a selective solute for 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) in the azeotropic or azeotropic-like composition. In another example, the conjugate fluid 28 may have a higher affinity for 1,1,2-trifluoroethane (HFC-143) and may act as a selective solute for 1,1,2-trifluoroethane (HFC-143) in the azeotropic or azeotropic-like composition.

[0073] The extraction column 26 is operated with operating parameters (temperature and pressure) such that the mixture of the first / dissolved component of the azeotropic or azeotropic-like composition and the accompanying fluid 28 is separated from the second component of the azeotropic or azeotropic-like composition. For example, if the accompanying fluid 28 has a higher affinity for 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and the accompanying fluid 28 are recovered in the bottom product 34 from the extraction column 26, while the concentrated 1,1,2-trifluoroethane (HFC-143) is recovered as distillate 30. In another example, if the conjugate fluid 28 has a higher affinity for 1,1,2-trifluoroethane (HFC-143), 1,1,2-trifluoroethane (HFC-143) and the conjugate fluid 28 are recovered in the bottom product 34, while the concentrated 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) is recovered as distillate 30.

[0074] In the second step, the bottom product 34, which contains each of the dissolved first component of the azeotropic or azeotropic-like composition and the mixture with the conjugate fluid, is transported to the recovery column 32. The recovery column 32 is operated with operating parameters (temperature and pressure) such that the conjugate fluid and the dissolved component of the azeotropic or azeotropic-like composition are separated from each other, where the concentrated conjugate fluid is recovered from the extraction column 26 as the bottom product 34, and either the concentrated 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) or 1,1,2-trifluoroethane (HFC-143) is recovered as the distillate 38. The recovered concentrated conjugate fluid can be recycled as described above and used as the conjugate fluid 28 in the extraction column 26. [Examples]

[0075] Example 1: Measurement and characterization of azeotropic properties and azeotropic-like compositions of 1,1,2-trifluoroethane (HFC-143) and 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) The azeotropic properties and azeotropic-like compositions of 1,1,2-trifluoroethane (HFC-143) and 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) were measured using an everiometer. An isobaric everiometer with a boiling section, an equilibrium section, and a condensing section was used. A Cottrell pump, a passive device for enabling vapor / liquid phase movement via boiling force, was fluidly connected between the boiling section and the equilibrium section, allowing the mixture to achieve total reflux and ultimately thermodynamic equilibrium. The everiometer was equipped with a pressure transducer with a calibration range of 1 to 500 psia and a resolution of 0.1 psia, as well as a pressure control unit that allowed the everiometer to be set to a pressure corresponding to the range of the equipped transducer. A platinum PT100 resistance temperature detector (RTD) with a calibration range of -40 to 200°C and a resolution of 0.001°C was inserted into the equilibrium section. A cartridge heater with a maximum heating supply of 300W, regulated by a 120V variable transformer, was inserted into the boiling section. A cooler connected to the utility side of the condensing section, controlled between -30 and 135°C with a 1°C setpoint resolution, ensured that all vapor from the system was condensed and returned to the everometer, maintaining the overall mass balance while avoiding flooding (i.e., accumulation of liquid in the equilibrium and condensing sections). A viewing window positioned between the condensing and equilibrium sections allowed for visual confirmation of total reflux or undesirable flooding.

[0076] To measure and determine the azeotropic or azeotropic-like properties, the following procedure was followed. 1. The isobaric everometer was pressure-checked to 350 psia with dry nitrogen to ensure that the connections were leak-free. 2. The everiometer was evacuated to at least 10 microns to remove the pressure test gas and any residual contaminants. 3. The temperature of the condenser is set to -10°C via a connected cooler, which is cold enough to condense HFC-143 vapor (which has a saturation temperature of approximately 3.9°C) and CFC-113 vapor (which has a saturation temperature of approximately 47.6°C) at 14.7 psia. 4. The pressure control unit was set to 14.7 psia. 5. Approximately 50 mL of HFC-143 was added to the boiling section of the everiometer. 6. Heat was applied to the boiling section by adjusting a variable transformer connected to the cartridge heater, increasing it in 5% increments until a total reflux of 60 to 120 drops of liquid per minute could be seen through the viewing window. 7. The temperature of the equilibrium zone was sampled every second. After thermodynamic equilibrium was achieved and realized by a stable temperature (180°C) with a fluctuation of less than 0.03°C over at least 3 minutes of the sample, the mean saturation temperature was recorded. 8. CFC-113 was added to the boiling portion from the top in increments of at least 0.5 mass%, and the overall mass balance was recorded. 9. The variable transformer was adjusted again to establish full recirculation, and the temperature of the equilibrium section was monitored for stability. 10. The gradual addition of CFC-113 to the everiometer was continued until the total volume added to the boiling section reached 100 mL (i.e., until the boiling section reached its capacity). 11. The everiometer was cooled, and the final mixture of HFC-143 and CFC-113 was removed. This procedure was repeated, but starting with 50 mL of CFC-113, and HFC-143 was gradually added to the everiometer following steps 5-10. 12. Records of pressure, saturation temperature, and composition from both sides (i.e., from HFC-143 start and CFC-113 start) were merged and organized so that saturation temperature as a functional composition could be observed.

[0077] For a fixed, single isobaric pressure, azeotropic compositions were identified by examining the saturation temperature as a function of the composition of HFC-143 and CFC-113. Azeotropic compositions corresponded to the case where the slope of the saturation temperature curve was equal to zero. In other words, azeotropic compositions existed when the saturation temperature was the overall minimum or maximum value relative to the pure saturation temperatures of both HFC-143 and CFC-113 at a fixed pressure. For a pressure of 14.7 psia, as shown in Figure 2 and Table 2, azeotropes with minimum boiling points were observed with compositions of 88.0 mass% HFC-143 and 12.0 mass% CFC-113, each with a standard boiling point of 3.736°C.

[0078] [Table 2]

[0079] Example 2: Azeotropic locus The procedure of Example 1 was repeated for each of the pressures shown in Table 3 below to generate azeotropic and azeotropic-like composition ranges.

[0080] Table 3 below contains azeotropic and azeotropic-like compositions of HFC-143 and CFC-113.

[0081] [Table 3]

[0082] Based on the above data, temperature glide and relative volatility were applied to determine azeotropic properties and azeotropic-like compositions.

[0083] The thermal glide and relative volatility of a mixture can be derived from thermodynamic measurements, such as those collected via an isobaric everometer, according to the mass balance and thermodynamic constraints. Several methods for deriving thermal glide from thermodynamic measurements are described in Sandler, SI (2006). Chapter 10: Vapor-Liquid Equilibrium in Mixtures. In Chemical, Biochemical, and Engineering Thermodynamics (4th ed., pp. 489-574), and include constraining thermodynamic consistency by the basic Gibbs-Duhem relation, as well as elucidating the vapor phase composition from the measurements by a combination of mass balance and equilibrium criteria (often called the Rachford-Rice equation or algorithm). This derivation confirms the relationship between equilibrium composition, temperature, and pressure, making it possible to evaluate thermal glide and relative volatility.

[0084] For a given composition, thermal glide is, by definition, the difference between the saturated vapor temperature and the saturated liquid temperature at a fixed pressure in thermodynamic equilibrium. Therefore, azeotropic compositions have a thermal glide of zero, and azeotropic-like compositions have a thermal glide that is substantially close to zero. A thermal glide of less than 0.5°C is substantially close to zero, and therefore, compositions satisfying such a thermal glide are considered azeotropic-like. This represents a broad azeotropic-like range.

[0085] Relative volatility, by definition, is the ratio of the vapor-to-liquid composition of the most volatile component to the vapor-to-liquid composition of the less volatile component at a fixed pressure in thermodynamic equilibrium. Therefore, azeotropic compositions have a relative volatility of 1.0, and azeotropic-like compositions have a relative volatility substantially close to 1.0. A relative volatility of 1.1 is substantially close to 1.0, and therefore compositions satisfying such a relative volatility are identified as azeotropic-like. This represents an intermediate azeotropic-like range.

[0086] Furthermore, a relative volatility of 1.05 is substantially close to 1.0, and therefore, compositions satisfying such relative volatility were identified as azeotropic. This represents a narrow azeotropic range.

[0087] Example 3: Pressure Swing Separation A well-known consequence of azeotropic mixtures is that their components cannot be completely separated in a single, continuous distillation operation. For example, the separation of a 50 / 50 mass% mixture of 1,1,2-trifluoroethane (HFC-143) and 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) by a continuous distillation column held at 14.7 psia exhibits azeotropic behavior as described in Example 1, constrained by the composition between the HFC-143 endpoint and the minimum boiling point of the azeotropic composition. In other words, distillation of the mixture under these conditions would not be able to produce HFC-143 with a purity greater than 88.0 mass%. To address this fundamental barrier of azeotropes and achieve purer HFC-143 and CFC-113, different separation strategies must be implemented.

[0088] As described in Example 1, the azeotropic compositions of HFC-143 and CFC-113 are pressure-sensitive. This sensitivity can be utilized to support better separation by pressure swing distillation. In this system, the pressure-sensitive azeotrope is separated using two distillation columns in sequence, one at any relatively low pressure and the other at any relatively high pressure. The columns may be arranged so that the low-pressure column is first in sequence, or the high-pressure column may be first in sequence. For the purposes of this example, referring to Figure 3, the columns are arranged so that the low-pressure column is first in sequence.

[0089] A mixture of HFC-143 and CFC-113 is first distilled at low pressure. The specific composition of the mixture may be adjusted as needed. For the purposes of this representative embodiment, a mixture containing 90% by mass of HFC-143 and 10% by mass of CFC-113 is used. Referring to Figure 3, this mixture (flow 10) is fed into the distillation column 12 at any low pressure.

[0090] The feed composition in flow 10 has not yet reached its azeotropic point with respect to the column pressure. Therefore, the mixture may separate into one component of the mixture and a fraction concentrated in the azeotropic or azeotropic-like composition. Here, the fraction concentrated with the low-boiling point component HFC-143 is collected as the bottom product, shown as flow 16 in Figure 4. The azeotropic or azeotropic-like composition is the distillate from the low-pressure column 12 shown in Figure 4. This mixture is then passed to column 18 at an arbitrary high pressure, following flow 14 in Figure 3.

[0091] When the composition of flow 14 is brought to the high pressure of column 18, its composition relative to the high-pressure azeotropic composition is lower at this point. This allows for the collection of a fraction in which the other components of the mixture are concentrated. In this embodiment, the fraction in which CFC-113 is concentrated is collected as the bottom product, shown as flow 20 in Figure 3. Similar to the low-pressure column, the distillate contains an azeotropic mixture or an azeotropic-like mixture. This mixture may be recirculated and mixed with the low-pressure column feed following flow 22 in Figure 3.

[0092] In this way, the azeotrope barrier is addressed using the composition's sensitivity to column conditions, producing two streams, each enriched with one of the components. It is important to note that the details of this embodiment are intended for illustrative purposes only. Depending on the context of the mixture, the column conditions and configuration can be designed to support almost any desired purity of HFC-143 and / or CFC-113.

[0093] Example 4: Extractive Distillation The azeotropic or azeotropic-like compositions of 1,1,2-trifluoroethane (HFC-143) and 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) are separated by extractive distillation. First, a stream containing the azeotropic or azeotropic-like compositions of 1,1,2-trifluoroethane (HFC-143) and 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) is fed into a first distillation column along with an adsorbent fluid. The extraction column is operated at appropriate temperature and pressure. The first distillation column functions as an extraction column, and one of the components of the azeotropic or azeotropic composition (e.g., component A) and the adsorbent fluid are recovered in the bottom product from the extraction column, while the other component of the azeotropic or azeotropic composition (e.g., component B) is recovered. Here, the adjunct fluid is selected based on various thermodynamic properties, including the difference in affinity between component A and component B that dissolve in the adjunct fluid, so that substantially all of component A dissolves in the adjunct fluid, while component B is hardly soluble or not soluble at all. The column is operated based on the thermodynamic difference between the adjunct / component A and component B, as described in relation to "Example 3: Pressure Swing Distillation". The extraction column is operated so that the distillate contains substantially all of component B and the bottom product contains substantially all of the adjunct fluid and dissolved component A.

[0094] The recovered adjunct fluid and dissolved component A are fed into a second recovery column operated at appropriate temperature and pressure. The recovery column separates the adjunct fluid from component A based on thermodynamic difference, as described in relation to "Example 3: Pressure Swing Distillation." Here, substantially all of the adjunct fluid is recovered in the bottom product from the recovery column, and substantially all of component A is recovered in the distillate. The recovered adjunct fluid is then recycled to the extraction column.

[0095] Example 5: A process for separating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) from 1,1,2-trifluoroethane (HFC-143) in a process for producing 1,1,2-trifluoroethane (HFC-143). A reagent stream containing CFCl2-CF2Cl (CFC-113) and hydrogen (H2) is supplied to the hydrogenation reactor. The hydrogenation reactor is operated at a temperature of 200°C to 300°C, a pressure of 10 psig to 200 psig, and a contact time of 1 second to 60 seconds. The hydrogenation reactor contains a platinum-containing catalyst on a carbon support. After the reaction, the product stream from the reaction is analyzed by an everometer, as in Examples 1 to 4 above. The product stream has been found to contain at least HCl and an azeotropic or azeotropic-like composition of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143). Specifically, azeotropic or azeotropic-like compositions of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) have been found to contain approximately 12.0% to 1.1% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and approximately 88.0% to 98.9% by weight of 1,1,2-trifluoroethane (HFC-143). The product stream is then separated, “decomposing” the azeotropic or azeotropic composition of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) into individual components, thereby further separating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) from each other. For example, the azeotropic or azeotropic composition of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) is “decomposed” and separated by either pressure swing distillation or extractive distillation, as described with reference to Examples 3 and 4 above. 1,1,2-Trichloro-1,2,2-trifluoroethane (CFC-113) is removed during the separation process, and the resulting product stream contains HCl and 1,1,2-trifluoroethane (HFC-143). HCl is then removed. The final recovered product is found to contain 90 mol% to 99.5 mol% 1,1,2-trifluoroethane (HFC-143).

[0096] manner Embodiment 1 is an azeotropic or azeotropic-like composition essentially consisting of effective amounts of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143).

[0097] Embodiment 2 is an azeotropic or azeotropic-like composition according to either the preceding or subsequent embodiment, essentially consisting of about 77.6% to about 99.9% by weight of 1,1,2-trifluoroethane (HFC-143) and about 0.1% to about 22.4% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113).

[0098] Embodiment 3 is an azeotropic or azeotropic-like composition according to either the preceding or subsequent embodiment, essentially consisting of about 83.7% to about 96.1% by weight of 1,1,2-trifluoroethane (HFC-143) and about 3.9% to about 16.3% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113).

[0099] Embodiment 4 is an azeotropic or azeotropic-like composition according to either the preceding or subsequent embodiment, essentially consisting of about 85.8% to about 94.8% by weight of 1,1,2-trifluoroethane (HFC-143) and about 5.2% to about 14.2% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113).

[0100] Embodiment 5 is an azeotropic or azeotropic-like composition according to either the preceding or subsequent embodiment, essentially consisting of about 12.0% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 88.0% by weight of 1,1,2-trifluoroethane (HFC-143).

[0101] Embodiment 6 is an azeotropic or azeotropic composition according to either the preceding or subsequent embodiment, wherein the azeotropic or azeotropic-like composition has a boiling point ranging from 3.7°C at a pressure of about 14.7 psia to about 79.7°C at a pressure of about 165.2 psia.

[0102] Embodiment 7 is a method for producing 1,1,2-trifluoroethane (HFC-143), comprising: hydrogenating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) with hydrogen (H2) to form a product mixture, wherein the product mixture contains an azeotropic or azeotropic-like composition essentially consisting of an effective amount of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143); and separating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143) to provide a product composition containing 1,1,2-trifluoroethane (HFC-143).

[0103] Embodiment 8 is a method according to any of the preceding or subsequent embodiments, further comprising recirculating 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to a hydrogenation step.

[0104] Embodiment 9 is a method according to any of the preceding or subsequent embodiments, wherein the separation step comprises transporting a product mixture to a first column having a first pressure; collecting a first bottom product from the first column; and transporting a first distillate from the first column to a second column having a second pressure to provide a second distillate and a second bottom product, wherein the second distillate contains an azeotropic or azeotropic composition.

[0105] Embodiment 10 is a method according to any of the preceding or subsequent embodiments, wherein the pressure in the first column is lower than the pressure in the second column, the first column bottom product consists essentially of 1,1,2-trifluoroethane (HFC-143), and the second column bottom product consists essentially of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113).

[0106] Embodiment 11 is a method according to either the earlier or later embodiment, wherein the pressure in the first column is higher than the pressure in the second column, the first column bottom product consists essentially of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), and the second column bottom product consists essentially of 1,1,2-trifluoroethane (HFC-143).

[0107] Embodiment 12 is a method according to any of the preceding or subsequent embodiments, which includes an additional step of recirculating the second distillate to the first column.

[0108] Embodiment 13 is a method according to any of the preceding or subsequent embodiments, wherein the separation step includes transporting the product mixture and the conjugate fluid to a first column; collecting a first distillate from a first column containing a first component of an azeotropic or azeotropic-like composition; collecting a first bottom product from a first column containing a mixture of the conjugate and a second component of an azeotropic or azeotropic-like composition; transporting the first bottom product to a second column to separate the conjugate from the second component of an azeotropic or azeotropic-like composition; and removing the composition containing the second component of an azeotropic or azeotropic-like composition as a second distillate from a second column.

[0109] Embodiment 14 is a method according to either the earlier or later embodiment, wherein the first component of the azeotropic or azeotropic-like composition essentially consists of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), and the second component of the azeotropic or azeotropic-like composition essentially consists of 1,1,2-trifluoroethane (HFC-143).

[0110] Embodiment 15 is a method according to either the earlier or later embodiment, wherein the first component of the azeotropic or azeotropic-like composition essentially consists of 1,1,2-trifluoroethane (HFC-143), and the second component of the azeotropic or azeotropic-like composition essentially consists of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113).

[0111] Embodiment 16 is an azeotropic or azeotropic-like composition produced by any one of the methods of Embodiments 7 to 15.

[0112] Embodiment 17 is a composition comprising an azeotropic or azeotropic-like composition that is essentially derived from any of Embodiments 1 to 6, or obtained from any of Embodiments 7 to 15.

[0113] Embodiment 18 is a composition comprising 1,1,2-trifluoroethane (HFC-143) produced by any of the methods of Embodiments 7 to 15.

Claims

1. An azeotropic or azeotropic-like composition essentially consisting of effective amounts of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143).

2. The azeotropic or azeotropic-like composition according to claim 1, comprising essentially about 77.6% to about 99.9% by weight of 1,1,2-trifluoroethane (HFC-143) and about 0.1% to about 22.4% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113).

3. The azeotropic or azeotropic-like composition according to claim 1, comprising essentially about 83.7% to about 96.1% by weight of 1,1,2-trifluoroethane (HFC-143) and about 3.9% to about 16.3% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113).

4. The azeotropic or azeotropic-like composition according to claim 1, comprising essentially about 85.8% to about 94.8% by weight of 1,1,2-trifluoroethane (HFC-143) and about 5.2% to about 14.2% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113).

5. The azeotropic or azeotropic-like composition according to claim 1, comprising essentially about 12.0% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and about 88.0% by weight of 1,1,2-trifluoroethane (HFC-143).

6. The azeotropic or azeotropic composition according to claim 1, wherein the azeotropic or azeotropic-like composition has a boiling point ranging from about 3.7°C at a pressure of about 14.7 psia to about 79.7°C at a pressure of about 165.2 psia.

7. A method for producing 1,1,2-trifluoroethane (HFC-143), 1,1,2-Trichloro-1,2,2-trifluoroethane (CFC-113) is converted to hydrogen (H ２ Hydrogenation involves hydrogenating with a product mixture, wherein the product mixture contains an azeotropic or azeotropic-like composition essentially consisting of an effective amount of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and 1,1,2-trifluoroethane (HFC-143), A method comprising separating the 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) and the 1,1,2-trifluoroethane (HFC-143) to provide a product composition containing the 1,1,2-trifluoroethane (HFC-143).

8. The method according to claim 7, further comprising recirculating the 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) to the hydrogenation step.

9. The aforementioned separation step is The product mixture is transported to a first tower having a first pressure, Collecting the first column base product from the first column, The first distillate is transported from the first column to a second column having a second pressure to provide a second distillate and a second column bottom product, wherein the second distillate contains the azeotropic or azeotropic-like composition, and the transport is carried out accordingly. The method according to claim 7, comprising collecting a second column bottom product from the second column.

10. The method according to claim 9, wherein the pressure in the first column is lower than the pressure in the second column, the first column bottom product consists essentially of 1,1,2-trifluoroethane (HFC-143), and the second column bottom product consists essentially of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113).

11. The method according to claim 9, wherein the pressure in the first column is higher than the pressure in the second column, the first column bottom product is essentially composed of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), and the second column bottom product is essentially composed of 1,1,2-trifluoroethane (HFC-143).

12. The method according to claim 9, further comprising the additional step of recirculating the second distillate to the first column.

13. The aforementioned separation step is The product mixture and the accompanying fluid are transported to the first column. The first distillate is collected from the first column containing the first component of the azeotropic or azeotropic-like composition, The first column bottom product is collected from the first column containing a mixture of the adjuvant and the second component of the azeotropic or azeotropic-like composition, In order to separate the adjuvant from the second component of the azeotropic or azeotropic-like composition, the first column bottom product is transported to the second column, The method according to claim 7, comprising removing a composition containing the second component of the azeotropic or azeotropic-like composition from the second column as a second distillate.

14. The method according to claim 13, wherein the first component of the azeotropic or azeotropic-like composition essentially consists of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), and the second component of the azeotropic or azeotropic-like composition essentially consists of 1,1,2-trifluoroethane (HFC-143).

15. The method according to claim 13, wherein the first component of the azeotropic or azeotropic-like composition essentially consists of 1,1,2-trifluoroethane (HFC-143), and the second component of the azeotropic or azeotropic-like composition essentially consists of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113).

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