Composition comprising 1,1,1,2 - tetrafluoroethane, and method for storing same

Abstract

To provide a composition in which a decrease in the concentration of 1,1,1,2 - tetrafluoroethane is suppressed during storage.SOLUTION: A composition comprising 1,1,1,2 - tetrafluoroethane and a fluorocarbon-based compound having one or more double bonds, wherein the oxygen concentration is 5.0 ppm by volume or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to compositions containing 1,1,1,2-tetrafluoroethane and methods for storing same. [Background technology]

[0002] 1,1,1,2-tetrafluoroethane may contain fluorocarbon compounds having double bonds as impurities. Summary of the Invention [Problem to be solved by the invention]

[0003] It has been found that fluorocarbon compounds having double bonds contained in compositions containing 1,1,1,2-tetrafluoroethane may convert to other compounds during storage, which may reduce the purity of the 1,1,1,2-tetrafluoroethane.

[0004] An object of the present disclosure is to provide a composition in which the decrease in the concentration of 1,1,1,2-tetrafluoroethane during storage is suppressed. [Means for solving the problem]

[0005] The present disclosure includes the following aspects. [Section 1] A composition comprising 1,1,1,2-tetrafluoroethane and a fluorocarbon compound having one or more double bonds, wherein the oxygen concentration, hydrogen fluoride concentration, or hydrogen chloride concentration is 5.0 ppm by volume or less. [Section 2] Item 1. The composition according to item 1, wherein the oxygen concentration is 5.0 ppm by volume or less. [Section 3] Item 1. The composition according to item 1, wherein the hydrogen fluoride concentration is 5.0 ppm by volume or less. [Section 4] Item 1. The composition according to item 1, wherein the hydrogen chloride concentration is 5.0 ppm by volume or less. [Section 5] Item 5. The composition according to any one of items 1 to 4, wherein the fluorocarbon compound having a double bond has one double bond. [Section 6] Item 6. The composition according to any one of Items 1 to 5, wherein the fluorocarbon compound having a double bond has 2 or 3 carbon atoms. [Section 7] Item 7. The composition according to any one of items 1 to 6, wherein the fluorocarbon compound having a double bond comprises at least one compound selected from the group consisting of (E / Z)1-chloro-1,2-difluoroethene, (E / Z)1-chloro-2-fluoroethene, and 3,3,3-trifluoropropene. [Section 8] 8. The composition according to any one of items 1 to 7, wherein the oxygen concentration is 0.1 ppm by volume or more and 5.0 ppm by volume or less. [Section 9] Item 9. The composition according to any one of items 1 to 8, wherein the oxygen concentration is 0.1 ppm by volume or more and 1.0 ppm by volume or less. [Section 10] Item 10. The composition according to any one of items 1 to 9, wherein the concentration of the fluorocarbon compound having one or more double bonds is 0.1 ppm by volume or more and 50 ppm by volume or less. [Section 11] Item 11. The composition according to any one of Items 1 to 10, wherein the concentration of the fluorocarbon compound having one or more double bonds is 0.1 ppm by volume or more and 2.0 ppm by volume or less. [Section 12] 12. The composition according to any one of items 1 to 11, wherein the concentration of 1,1,1,2-tetrafluoroethane is 99.9999% by volume or more. [Section 13] A method for storing a composition containing 1,1,1,2-tetrafluoroethane and a fluorocarbon compound having one or more double bonds, the method comprising adjusting the oxygen concentration, hydrogen fluoride concentration, or hydrogen chloride concentration to 5.0 ppm by volume or less. [Section 14] Item 14. The method for preserving according to Item 13, wherein the oxygen concentration, hydrogen fluoride concentration, or hydrogen chloride concentration is 0.1 ppm by volume or more and 5.0 ppm by volume or less. [Section 15] Item 15. The method for storage according to Item 13 or 14, wherein the storage temperature is 50°C or lower. [Section 16] Item 16. The storage method according to any one of Items 13 to 15, wherein the storage temperature is 0°C or higher and 50°C or lower. [Effects of the Invention]

[0006] According to the composition of the present disclosure, the decrease in the concentration of 1,1,1,2-tetrafluoroethane is suppressed. DETAILED DESCRIPTION OF THE INVENTION

[0007] The composition of the present disclosure contains 1,1,1,2-tetrafluoroethane and a fluorocarbon-based compound having one or more double bonds, and has an oxygen concentration, hydrogen fluoride concentration, or hydrogen chloride concentration of 5.0 ppm by volume or less.

[0008] In one embodiment, the oxygen concentration is 5.0 ppm by volume or less.

[0009] In another embodiment, the hydrogen fluoride concentration is 5.0 ppm by volume or less.

[0010] In another embodiment, the hydrogen chloride concentration is 5.0 ppm by volume or less.

[0011] In a preferred embodiment, the concentrations of two of the oxygen concentration, hydrogen fluoride concentration, and hydrogen chloride concentration are 5.0 ppm by volume or less. For example, the hydrogen fluoride concentration and hydrogen chloride concentration are 5.0 ppm by volume or less, or the oxygen concentration and hydrogen chloride concentration are 5.0 ppm by volume or less, or the oxygen concentration and hydrogen fluoride concentration are 5.0 ppm by volume or less.

[0012] In a more preferred embodiment, the oxygen concentration, hydrogen fluoride concentration, and hydrogen chloride concentration are 5.0 ppm by volume or less.

[0013] A mixed gas containing 1,1,1,2-tetrafluoroethane may contain fluorocarbon compounds having double bonds. Such fluorocarbon compounds may be converted into other compounds during storage, resulting in a decrease in the concentration of 1,1,1,2-tetrafluoroethane. The composition containing 1,1,1,2-tetrafluoroethane of the present disclosure has an oxygen concentration of 5.0 ppm by volume or less, which can inhibit the decomposition and / or polymerization of fluorocarbon compounds having double bonds into other compounds.

[0014] The fluorocarbon compound having a double bond is typically a hydrofluoroolefin (HFO).

[0015] Examples of hydrofluoroolefins (HFOs) include 2-chloro-1,1-difluoroethene (HFO-1122), (E / Z)1-chloro-1,2-difluoroethene (HFO-1122a), trifluoroethene (HFO-1123), (E / Z)1-chloro-2-fluoroethene (HFO-1131), 2,3,3,3-tetrafluoropropene (HFO-1234yf), 3,3,3-trifluoropropene (HFO-1243zf), trans-1,3,3,3-tetrafluoropropene (HFO-1234ze), and 1,3,3,3-tetrafluoropropene (HFO-1234zd).

[0016] In one embodiment, the fluorocarbon compound having a double bond has one double bond.

[0017] In one embodiment, the fluorocarbon compound having a double bond has 2 or 3 carbon atoms.

[0018] In a preferred embodiment, the fluorocarbon compound having a double bond includes at least one compound selected from the group consisting of (E / Z)1-chloro-1,2-difluoroethene, (E / Z)1-chloro-2-fluoroethene, and 3,3,3-trifluoropropene. The fluorocarbon compound having a double bond is preferably 1-chloro-1,2-difluoroethene, (E / Z)1-chloro-2-fluoroethene, or 3,3,3-trifluoropropene.

[0019] The oxygen concentration in the composition is 5.0 ppm by volume or less, preferably 3.0 ppm by volume or less, and more preferably 1.0 ppm by volume or less. By keeping the oxygen concentration at 5.0 ppm by volume or less, conversion of fluorocarbon compounds having double bonds to other compounds can be suppressed. The oxygen concentration is preferably 0.1 ppm by volume or more, for example, 0.2 ppm by volume or more or 0.3 ppm by volume or more. The oxygen concentration can be 0.1 to 5.0 ppm by volume, preferably 0.1 to 3.0 ppm by volume, more preferably 0.1 to 1.0 ppm by volume, for example, 0.2 to 3.0 ppm by volume, 0.3 to 3.0 ppm by volume, 0.2 to 1.0 ppm by volume, or 0.3 to 1.0 ppm by volume.

[0020] In the composition, the hydrogen fluoride concentration is 5.0 ppm by volume or less, preferably 3.0 ppm by volume or less, and more preferably 1.0 ppm by volume or less. By setting the hydrogen fluoride concentration to 5.0 ppm by volume or less, it is possible to prevent fluorocarbon compounds having double bonds from being converted to other compounds. Furthermore, the hydrogen fluoride concentration is preferably 0.1 ppm by volume or more, for example, 0.2 ppm by volume or more or 0.3 ppm by volume or more. By setting the hydrogen fluoride concentration to 0.1 ppm by volume or more, it is possible to prevent the decomposition of 1,1,1,2-tetrafluoroethane during storage. Without being limited by theory, this is thought to be because 1,1,1,2-tetrafluoroethane decomposes to trifluoroethene, and this decomposition reaction is an equilibrium reaction, and the presence of hydrogen fluoride can shift the equilibrium point toward 1,1,1,2-tetrafluoroethane. The hydrogen fluoride concentration can be 0.1 to 5.0 ppm by volume, preferably 0.1 to 3.0 ppm by volume, more preferably 0.1 to 1.0 ppm by volume, for example, 0.2 to 3.0 ppm by volume, 0.3 to 3.0 ppm by volume, 0.2 to 1.0 ppm by volume, or 0.3 to 1.0 ppm by volume.

[0021] The hydrogen chloride concentration in the composition is 5.0 ppm by volume or less, preferably 3.0 ppm by volume or less, and more preferably 1.0 ppm by volume or less. By maintaining the hydrogen chloride concentration at 5.0 ppm by volume or less, conversion of fluorocarbon compounds having double bonds to other compounds can be suppressed. Furthermore, the hydrogen chloride concentration can be preferably 0.1 ppm by volume or more, for example, 0.2 ppm by volume or more or 0.3 ppm by volume or more. By maintaining the hydrogen chloride concentration at 0.1 ppm by volume or more, a passivation film can be formed inside the container, improving the storage stability of the composition. The hydrogen chloride concentration can be 0.1 to 5.0 ppm by volume, preferably 0.1 to 3.0 ppm by volume, more preferably 0.1 to 1.0 ppm by volume, for example, 0.2 to 3.0 ppm by volume, 0.3 to 3.0 ppm by volume, 0.2 to 1.0 ppm by volume, or 0.3 to 1.0 ppm by volume.

[0022] The concentration of the fluorocarbon compound having a double bond is preferably 50 ppm by volume or less, more preferably 20 ppm by volume or less, even more preferably 10 ppm by volume or less, for example, 5.0 ppm by volume or less or 1.0 ppm by volume or less. The concentration of the fluorocarbon compound having a double bond is preferably 0.1 ppm by volume or more, for example, 0.2 ppm by volume or more or 0.2 ppm by volume or more. The concentration of the fluorocarbon compound having a double bond is preferably 0.1 to 50 ppm by volume, preferably 0.1 to 20 ppm by volume, more preferably 0.1 to 10 ppm by volume, even more preferably 0.1 to 5.0 ppm by volume.

[0023] The concentration of 1,1,1,2-tetrafluoroethane is preferably 99.9990% by volume or more, and more preferably 99.9999% by volume or more.

[0024] The present disclosure also provides a method for storing a composition containing 1,1,1,2-tetrafluoroethane and a fluorocarbon compound having one or more double bonds, the method comprising maintaining an oxygen concentration of 5.0 ppm by volume or less.

[0025] The storage temperature may be preferably 60°C or lower, more preferably 50°C or lower, and even more preferably 40°C or lower. By setting the storage temperature to 60°C or lower, conversion of the fluorocarbon compound having a double bond to other compounds can be suppressed. Furthermore, the storage temperature may be preferably 0°C or higher, for example, 10°C or higher, 15°C or higher, or 20°C or higher. The storage method of the present disclosure can sufficiently suppress conversion of the fluorocarbon compound having a double bond to other compounds even at temperatures above 0°C, so excessive cooling is not necessary. For example, room temperature may be used. The storage temperature may be preferably 0 to 60°C, preferably 0 to 50°C, for example, 10 to 50°C, or 20 to 50°C.

[0026] In a preferred embodiment, the storage is carried out in a dark place. The container may be a light-blocking container, and the storage location may be a dark place. [Example]

[0027] The purification method of the present disclosure will be explained in more detail below through the following examples, but the present disclosure is not limited to these examples.

[0028] (Initial composition 1) Compositions 1 to 9 containing 1,1,1,2-tetrafluoroethane (HFC-134a), (E / Z)1-chloro-1,2-difluoroethene (HFO-1122a), (E / Z)1-chloro-2-fluoroethene (HFO-1131), and 3,3,3-trifluoropropene (HFO-1243zf) in the proportions shown in Table 1 below were prepared.

[0029] [Table 1]

[0030] (Example) For each of the above compositions 1 to 9, the oxygen concentration was adjusted to 100 ppm by volume, 10 ppm by volume, 5 ppm by volume, and 1 ppm by volume, and the gas compositions were stored at 20°C and 50°C. 30, 90, and 180 days after the start of storage, the gas compositions were analyzed by chromatography. The contents of components not contained in the initial compositions were calculated, and the results at 20°C are shown in Table 2, and the results at 50°C are shown in Table 3. ND indicates below the detection limit (0.1 ppm by volume or less).

[0031] [Table 2]

[0032] [Table 3]

[0033] Example 2 For each of the above compositions 1 to 9, the hydrogen fluoride concentrations were adjusted to 100 ppm by volume, 10 ppm by volume, 5 ppm by volume, and 1 ppm by volume, and the samples were stored at 20°C and 50°C. After 30, 90, and 180 days of storage, the gas compositions were analyzed by chromatography. The contents of components not contained in the initial compositions were calculated, and the results at 20°C are shown in Table 4, and the results at 50°C are shown in Table 5. ND indicates below the detection limit (0.1 ppm by volume or less).

[0034] [Table 4]

[0035] [Table 5]

[0036] Example 3 For each of the above compositions 1 to 9, the hydrogen chloride concentrations were adjusted to 100 ppm by volume, 10 ppm by volume, 5 ppm by volume, and 1 ppm by volume, and the compositions were stored at 20°C and 50°C. After 30, 90, and 180 days of storage, the gas compositions were analyzed by chromatography. The contents of components not contained in the initial compositions were calculated, and the results at 20°C are shown in Table 6, and the results at 50°C are shown in Table 7. ND indicates below the detection limit (0.1 ppm by volume or less).

[0037] [Table 6]

[0038] [Table 7]

[0039] Example 4 (E / Z)1-chloro-1,2-difluoroethene (HFO-1122a), (E / Z)1-chloro-2-fluoroethene (HFO-1131), and 3,3,3-trifluoropropene (HFO-1243zf) were adjusted to oxygen concentrations of 0.1 ppm by volume and 0.01 ppm by volume, respectively, and stored at 20°C and 50°C. After 30, 90, and 180 days of storage, the gas compositions were analyzed by chromatography. The contents of components not contained in the initial compositions were calculated, and the results at 20°C and 50°C are shown in Table 9 and Table 10, respectively.

[0040] [Table 8]

[0041] [Table 9]

[0042] [Table 10]

[0043] Examples 5 and 6 1,1,1,2-Tetrafluoroethane (HFC-134a) was purified to obtain high-purity HFC-134a in which no components other than HFC-134a were detected by gas chromatography. To this was added hydrogen fluoride to a concentration of 0.1 ppm by volume. The mixture was stored at 20°C and 50°C. The gas composition was analyzed by chromatography 30, 90, and 180 days after storage. The results for 20°C and 50°C are shown in Table 11 and Table 12, respectively.

[0044] (Comparative Examples 1 and 2) High-purity HFC-134a was stored at 20°C and 50°C without added hydrogen fluoride. The gas composition was analyzed by chromatography after 30, 90, and 180 days of storage. The results for 20°C and 50°C are shown in Table 4 and Table 5, respectively.

[0045] [Table 11]

[0046] [Table 12] [Industrial Applicability]

[0047] Compositions containing 1,1,1,2-tetrafluoroethane of the present disclosure are suitable for long-term storage.

Claims

1. A composition comprising 1,1,1,2-tetrafluoroethane and a fluorocarbon compound having one or more double bonds, wherein the composition has an oxygen concentration, a hydrogen fluoride concentration, or a hydrogen chloride concentration of 5.0 ppm by volume or less.

2. 10. The composition of claim 1, wherein the oxygen concentration is 5.0 ppm by volume or less.

3. 2. The composition of claim 1, wherein the hydrogen fluoride concentration is 5.0 ppm by volume or less.

4. 10. The composition of claim 1, wherein the hydrogen chloride concentration is 5.0 ppm by volume or less.

5. The composition according to claim 1 , wherein the fluorocarbon compound having a double bond has one double bond.

6. 2. The composition according to claim 1, wherein the fluorocarbon compound having a double bond has 2 or 3 carbon atoms.

7. 2. The composition according to claim 1, wherein the fluorocarbon compound having a double bond comprises at least one compound selected from the group consisting of (E / Z)1-chloro-1,2-difluoroethene, (E / Z)1-chloro-2-fluoroethene, and 3,3,3-trifluoropropene.

8. 2. The composition according to claim 1, wherein the oxygen concentration, hydrogen fluoride concentration, or hydrogen chloride concentration is 0.1 ppm by volume or more and 5.0 ppm by volume or less.

9. The composition according to claim 1 , wherein the oxygen concentration, hydrogen fluoride concentration, or hydrogen chloride concentration is 0.1 ppm by volume or more and 1.0 ppm by volume or less.

10. 2. The composition according to claim 1, wherein the concentration of the fluorocarbon compound having one or more double bonds is 0.1 ppm by volume or more and 50 ppm by volume or less.

11. 2. The composition according to claim 1, wherein the concentration of the fluorocarbon compound having one or more double bonds is 0.1 ppm by volume or more and 2.0 ppm by volume or less.

12. 2. The composition of claim 1, wherein the concentration of 1,1,1,2-tetrafluoroethane is 99.9999% by volume or greater.

13. A method for storing a composition containing 1,1,1,2-tetrafluoroethane and a fluorocarbon compound having one or more double bonds, the method comprising adjusting the oxygen concentration, hydrogen fluoride concentration, or hydrogen chloride concentration to 5.0 ppm by volume or less.

14. 14. The method for preservation according to claim 13, wherein the oxygen concentration, hydrogen fluoride concentration, or hydrogen chloride concentration is 0.1 ppm by volume or more and 5.0 ppm by volume or less.

15. The storage method according to claim 13, wherein the storage temperature is 50°C or lower.

16. The storage method according to claim 13, wherein the storage temperature is 0°C or higher and 50°C or lower.

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