Composition

Abstract

To provide a composition in which hydrogen fluoride from fluoroethylene is suppressed.SOLUTION: Provided is a composition that comprises fluoroethylene and epoxide having 6 or less carbon atoms.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to compositions. [Background technology]

[0002] Fluoroethylene is used in a variety of applications, including as a heat transfer medium, and demand for it is expected to continue to grow in the future.

[0003] On the other hand, when oxygen is mixed into fluoroethylene, it may gradually decompose to produce hydrogen fluoride. The produced hydrogen fluoride may cause deterioration of the refrigeration oil, which may in turn cause corrosion or damage to the equipment or container. To prevent this, efforts have been made to suppress oxygen contamination and to add acid scavengers to the refrigeration oil added to fluoroethylene.

[0004] Patent Document 1 discloses a fluoroethylene-containing composition containing a polymerization inhibitor, and Patent Document 2 discloses an embodiment in which an antioxidant is contained in a refrigerating machine oil. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-14594 [Patent Document 2] International Publication No. 2020 / 017522 Summary of the Invention [Problem to be solved by the invention]

[0006] In view of the above circumstances, an object of the present disclosure is to provide a composition in which the production of hydrogen fluoride from fluoroethylene is suppressed. [Means for solving the problem]

[0007] As a result of intensive research aimed at solving the above problems, the present inventors have found that the production of hydrogen fluoride can be suppressed by allowing fluoroethylene to coexist with an epoxide having 6 or less carbon atoms. Based on this finding, the present inventors have conducted further research and have completed the present disclosure.

[0008] That is, the present disclosure provides the following compositions: Section 1. A composition comprising fluoroethylene and an epoxide having 6 or less carbon atoms. Section 2. Item 2. The composition according to Item 1, wherein the content of the epoxide is 1 to 50,000 ppm by mass based on the mass of the fluoroethylene. Section 3. Item 3. The composition according to item 1 or 2, wherein the fluoroethylene has two or more fluorine atoms. Section 4. 4. The composition according to any one of items 1 to 3, further comprising oxygen, the oxygen content being 1 to 5000 mole ppm based on the number of moles of the fluoroethylene. Section 5. 5. The composition according to any one of items 1 to 4, further comprising water, the content of which is 0.1 to 100 ppm by mass based on the mass of the fluoroethylene. Section 6. Item 6. The composition according to any one of Items 1 to 5, which is a heat transfer medium, a foaming agent, or a propellant. [Effects of the Invention]

[0009] The compositions of the present disclosure inhibit the production of hydrogen fluoride. DETAILED DESCRIPTION OF THE INVENTION

[0010] In this specification, the term "containing" is a concept that encompasses all of "comprise," "consist essentially of," and "consist only of." Furthermore, in this specification, when a numerical range is expressed as "A to B," it means A or more and B or less.

[0011] The composition of the present disclosure includes fluoroethylene and an epoxide having up to 6 carbon atoms.

[0012] The fluoroethylene contained in the composition of the present disclosure is not particularly limited. The number of fluorines in the fluoroethylene is preferably 2 or more, more preferably 2 or 3, and particularly preferably 2.

[0013] From the viewpoint of easier improvement in stability, the fluoroethylene is preferably one or more selected from the group consisting of 1,2-difluoroethylene and trifluoroethylene, and more preferably 1,2-difluoroethylene.

[0014] Here, 1,2-difluoroethylene exists as two isomers (E isomer and Z isomer); specifically, there are two types: trans-1,2-difluoroethylene (HFO-1132(E)) and cis-1,2-difluoroethylene (HFO-1132(Z)). In the fluoroethylene composition of the present disclosure, when the fluoroethylene is 1,2-difluoroethylene, it may be either one of the isomers alone, or a mixture of both isomers. That is, when the fluoroethylene is 1,2-difluoroethylene in the composition of the present disclosure, the 1,2-difluoroethylene can be trans-1,2-difluoroethylene (HFO-1132(E)) and / or cis-1,2-difluoroethylene (HFO-1132(Z)).

[0015] When the fluoroethylene is 1,2-difluoroethylene, the 1,2-difluoroethylene is preferably the E-isomer. Specifically, the 1,2-difluoroethylene preferably contains 50% by mass or more of the E-isomer, more preferably 55% by mass or more, even more preferably 60% by mass or more, and particularly preferably 70% by mass or more.

[0016] In this specification, the term "1,2-difluoroethylene" or "HFO-1132" encompasses all of E-isomers of 1,2-difluoroethylene, Z-isomers of 1,2-difluoroethylene, and a mixture of E- and Z-isomers of 1,2-difluoroethylene. In this specification, where necessary, E-isomers of 1,2-difluoroethylene will be expressed as "1,2-difluoroethylene (E)" or "HFO-1132(E)," Z-isomers of 1,2-difluoroethylene will be expressed as "1,2-difluoroethylene (Z)" or "HFO-1132(Z)," and a mixture of E- and Z-isomers of 1,2-difluoroethylene will be expressed as "1,2-difluoroethylene (E,Z)" or "HFO-1132(E,Z)."

[0017] In the composition of the present disclosure, the method for producing fluoroethylene is not particularly limited, and fluoroethylene can be produced, for example, by a known production method. When the fluoroethylene contained in the composition of the present disclosure is 1,2-difluoroethylene, 1,2-difluoroethylene can be produced by the dehydrofluorination reaction of 1,1,2-trifluoroethane, the hydrogenation reaction of 1,2-dichloro-1,2-difluoroethylene, the hydrogenolysis of 1,2-dichlorodifluoroethylene, or the dehydrochlorination reaction of 1-chloro-1,2-difluoroethane.

[0018] The epoxide contained in the composition of the present disclosure has 6 or less carbon atoms, preferably 3 or less carbon atoms, and more preferably an epoxide with 2 carbon atoms. The content of the epoxide is preferably 1 ppm by mass or more, more preferably 5 ppm by mass or more, and even more preferably 50 ppm by mass or more, based on the mass of fluoroethylene. This makes it easier to obtain the effect of suppressing the generation of hydrogen fluoride, and can effectively suppress deterioration of equipment and the composition due to the generation of hydrogen fluoride.

[0019] The content of the epoxide is preferably 50,000 ppm by mass or less, more preferably 5,000 ppm by mass or less, and even more preferably 500 ppm by mass or less, based on the mass of fluoroethylene.

[0020] By setting the epoxide content to 50,000 ppm by mass or less based on the mass of fluoroethylene, it is possible to suppress deterioration of the composition due to side reactions caused by the epoxide and to prevent changes in the physical properties of the fluoroethylene.

[0021] The content of fluoroethylene and its epoxide in the composition of the present disclosure can be determined by a known analytical method such as gas chromatography.

[0022] The method for producing the fluoroethylene epoxide contained in the composition of the present disclosure is not particularly limited, and a wide variety of known methods can be used. For example, the fluoroethylene epoxide can be obtained by contacting the fluoroethylene with an oxidizing agent in a liquid or gas phase.

[0023] The oxidizing agent is not particularly limited and may be any known oxidizing agent used in the art, specifically, chlorine compounds such as chlorate, chlorite, and hypochlorite, bromine compounds such as bromate, bromite, and hypobromite, oxygen, etc.

[0024] When oxygen is contained in the composition of the present disclosure, the oxygen content is preferably 1 molar ppm or more, more preferably 3 molar ppm or more, and even more preferably 5 molar ppm or more, based on the number of moles of fluoroethylene. By making the oxygen content 1 molar ppm or more based on the number of moles of fluoroethylene, there is an advantage that an epoxide can be produced from the fluoroethylene.

[0025] The oxygen content of the composition of the present disclosure is preferably 5000 mol ppm or less, more preferably 3000 mol ppm or less, and even more preferably 1000 mol ppm or less, based on the number of moles of fluoroethylene. By setting the oxygen content to 5000 mol ppm or less, based on the number of moles of fluoroethylene, there is an advantage in that undesired side reactions other than the production of epoxide, such as decomposition reactions and polymerization reactions, can be suppressed.

[0026] The oxygen content in the composition of the present disclosure can be quantified by measuring the oxygen content in the gas phase using a commercially available gas chromatograph or oxygen concentration meter and converting this measurement value into the oxygen content in the liquid phase.

[0027] When the composition of the present disclosure contains water, the water content is preferably 0.1 ppm by mass or more, more preferably 1 ppm by mass or more, and even more preferably 2 ppm by mass or more, based on the mass of fluoroethylene.

[0028] Furthermore, the content of water in the composition of the present disclosure is preferably 100 ppm by mass or less, more preferably 50 ppm by mass or less, and even more preferably 20 ppm by mass or less, based on the mass of fluoroethylene. By setting the water content to 100 ppm by mass or less, based on the mass of fluoroethylene, it is possible to suppress the generation of acids or solids due to side reactions, etc., and ensure the stability of the composition.

[0029] The water content in the composition of the present disclosure can be measured by known methods such as titration using a commercially available Karl Fischer water content analyzer.

[0030] In the composition of the present disclosure, the above-mentioned epoxide having 6 or less carbon atoms captures hydrogen fluoride, thereby suppressing the generation of hydrogen fluoride. Furthermore, in the composition of the present disclosure, when the epoxide contained in the composition of the present disclosure is an epoxide of fluoroethylene contained in the composition of the present disclosure, the fluoroethylene and epoxide have similar structures and therefore have close boiling points, resulting in excellent handleability of the composition.

[0031] The composition of the present disclosure may contain substances other than those described above, as long as the effects or purposes of the composition are not impaired. For example, it may contain impurities that may be mixed in during the production of fluoroethylene. Such impurities, for example, when the fluoroethylene is 1,2-difluoroethylene, include fluoroethylene, trifluoroethylene, 1,1,1-trifluoroethane, propylene, acetylene, difluoromethane, trifluoromethane, fluoromethane, 1,1,2-trifluoroethylene (HFO-1123), 1,1-difluoroethane (HFC-152a), fluoroethane (HFC-161), 1,1,2-trifluoroethane (HFC-143), 2-chloro-1,1,1-trifluoroethane (HCFC-133b), 1-chloro-1,1,2-trifluoroethane (HCFC-133), 1,1-dichloro-2,2,2-trifluoroethane (HCFC-123), 1-chloro-1,2-difluoroethane (HCFC-142a), 1,2-difluoroethane (HFC-152), chloro Difluoromethane (HCFC-22), 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,2,2-tetrafluoroethane (HFC-134), pentafluoroethane (HFC-125), 2,3,3,3-tetrafluoropropene (HFO-1234yf), 1,2,3,3,3-pentafluoropropene (HFO-1225ye), 1,3,3,3-tetrafluoropropene (H At least one selected from the group consisting of 1-chloro-2,2-difluoroethylene (HCFO-1122), 1-chloro-1,2-difluoroethylene (HCFO-1122a), 1-chloro-1,2-difluoroethylene (HCFO-1122a), ethylene, and the like can be mentioned.

[0032] When the composition of the present disclosure contains the impurities, the content thereof is not particularly limited, and may be, for example, 0.1 ppm by mass or more based on the mass of fluoroethylene. Preferably, the content of the impurities is 10,000 ppm by mass or less.

[0033] The compositions of the present disclosure may contain other components besides fluoroethylene that function as refrigerants, such as 2,3,3,3-tetrafluoropropene (HFO-1234yf), 1,3,3,3-tetrafluoropropene (HFO-1234ze), 1,1,2-trifluoroethylene (HFO-1123), 1,1-difluoroethylene (HFO-1132a), 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,1-trifluoroethane (HFC-143a), 1,1-difluoroethane (HFC-152a), difluoromethane (HFC-32), iodotrifluoromethane, carbon dioxide, propane, butane, and isobutane. When the composition of the present disclosure contains these components, the total amount of the components having refrigerant function is taken as 100% by mass, and the content of the other components in total is preferably 3 to 97% by mass, and more preferably 30 to 90% by mass.

[0034] When the composition of the present disclosure is used as a heat transfer medium, it may further contain a lubricating oil within a range that does not impair the effects of the composition of the present disclosure. The lubricating oil is not particularly limited, and for example, a wide range of known lubricating oils used for refrigerants, etc. may be used.

[0035] In this specification, the term "refrigerant" includes at least compounds assigned a refrigerant number (ASHRAE number) beginning with the letter R, which indicates the type of refrigerant, as defined by ISO 817 (International Organization for Standardization), and also includes compounds that have equivalent refrigerant properties even if they have not yet been assigned a refrigerant number. Refrigerants are broadly classified into "fluorocarbon compounds" and "non-fluorocarbon compounds" based on their chemical structure. "Fluorocarbon compounds" include chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and hydrofluorocarbons (HFCs).

[0036] The content of the refrigerant in the composition of the present disclosure is preferably 50% by mass or more. There is no particular upper limit to the amount of the refrigerant in the composition, and it can be, for example, 100% by mass.

[0037] Furthermore, the content of fluoroethylene in the refrigerant contained in the composition of the present disclosure is preferably 3 to 100 mass% of fluoroethylene per 100 mass% of the refrigerant, more preferably 5 to 70 mass%, and even more preferably 10 to 50 mass%.

[0038] Specific examples of lubricating oils include one or more selected from the group consisting of polyalkylene glycols, polyol esters, and polyvinyl ethers. Examples of polyalkylene glycols (PAGs) include "SUNICEP56" manufactured by Nippon Sun Oil Co., Ltd. Examples of polyol esters (POEs) include "Ze-GLESRB series" manufactured by ENEOS Corporation. Examples of polyvinyl ethers (PVEs) include "Daphne Hermetic Oil FVC-D series" manufactured by Idemitsu Kosan Co., Ltd.

[0039] The lubricating oil may be contained in an amount of preferably 1 to 50 mass %, more preferably 10 to 40 mass %, when the total amount of the composition of the present disclosure is taken as 100 mass %. However, since this amount varies depending on the specifications of the oil tank of the refrigerator, it is not particularly limited to this range.

[0040] The composition of the present disclosure may contain the above-mentioned lubricating oil antioxidants to the extent that the effects and purposes of the composition are not impaired. Specific examples of such antioxidants include 2,6-di-tert-butyl-p-cresol, 4-hydroxy-3-t-butylanisole, triethylamine, 4-t-butylpyrocatechol, α-methylstyrene, and potassium hydrogen phthalate. These may be used alone or in combination. The content of the antioxidant may be appropriately determined depending on the amount of lubricating oil used.

[0041] The composition of the present disclosure may further contain other additives in addition to those described above. When the composition of the present disclosure contains other additives, the content of the other additives may be 5% by mass or less, preferably 1% by mass or less, more preferably 0.1% by mass or less, and particularly preferably 0.05% by mass or less, based on the mass of the component having a refrigerant function.

[0042] The method for preparing the composition of the present disclosure is not particularly limited. For example, a fluoroethylene composition can be prepared by mixing fluoroethylene, its epoxide, and water in a predetermined mixing ratio. In this mixing, the aforementioned lubricating oil and / or other additives can also be added as appropriate. Furthermore, the oxygen content in the composition can be adjusted to a desired range by blowing air or oxygen into the composition.

[0043] In the production of fluoroethylene or its epoxide, the above-mentioned impurities may be present in the fluoroethylene or its epoxide. These impurities may be removed in advance by an appropriate method before preparing the composition, or the fluoroethylene or its epoxide may be used as is in the composition without removing the impurities.

[0044] The composition of the present disclosure can be used in a variety of applications, including as a heat transfer medium, a blowing agent, a propellant, etc. Such heat transfer mediums, blowing agents, propellants, etc. can maintain their quality over a long period of time because the generation of hydrogen fluoride is suppressed and deterioration is minimized.

[0045] Although the embodiments of the present invention have been described above, the present invention is not limited to these examples, and it goes without saying that the present invention can be embodied in various forms without departing from the spirit of the present invention. [Example]

[0046] Hereinafter, the embodiments of the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

[0047] <Evaluation method> (Fluoroethylene stability test) The stability test was performed as follows. 1,2-difluoroethylene was added to a glass tube (ID 8 mm Φ × OD 12 mm Φ × L 300 mm) with one end heat-sealed, so that the amount added was 8.9 mmol. 1,2-difluoroethylene epoxide, oxygen, and water were added in advance in predetermined amounts. The tube was then heat-sealed to a sealed state. The tube was then placed in a thermostatic chamber under an atmosphere of 175°C and maintained in this state for two weeks. The tube was then removed from the thermostatic chamber and allowed to cool. The appearance was inspected and the acid content of the gas inside the tube was analyzed to evaluate the stability of the fluoroethylene.

[0048] In the stability test of fluoroethylene, the analysis of the acid content in the gas was carried out as follows. After the cooling, the tube was filled with liquid nitrogen to completely solidify the gas remaining in the tube. The tube was then opened and gradually thawed, and the gas was collected in a Tedlar bag. 5 g of pure water was poured into the Tedlar bag, and the acid content was extracted into the pure water while being in close contact with the collected gas. The extracted solution was detected by ion chromatography to detect fluoride ions (F - The amount of fluoride ions obtained by measuring the content (ppm by mass) of hydrogen fluoride was taken as the amount of hydrogen fluoride produced.

[0049] Example 1 A stability test of the above fluoroethylene was carried out by adding 125 ppm by mass of 1,2-difluoroethylene epoxide and 100 ppm by mole of oxygen to the 1,2-difluoroethylene. When the tube was removed from the thermostatic chamber and the gas was analyzed, no hydrogen fluoride was found to be produced.

[0050] Example 2 Evaluation was carried out in the same manner as in Example 1, except that 125 ppm by mass of 1,2-difluoroethylene epoxide and 500 ppm by mole of oxygen were added in advance relative to the 1,2-difluoroethylene. The tube was removed from the thermostatic chamber and the gas was analyzed, revealing that 35 ppm by mass of hydrogen fluoride relative to the 1,2-difluoroethylene had been produced.

[0051] Example 3 Evaluation was carried out in the same manner as in Example 1, except that 70 ppm by mass of 1,2-difluoroethylene epoxide and 500 ppm by mole of oxygen were added in advance relative to the 1,2-difluoroethylene. The tube was removed from the thermostatic chamber and the gas was analyzed, revealing that 49 ppm by mass of hydrogen fluoride relative to the 1,2-difluoroethylene had been produced.

[0052] (Comparative Example 1) Evaluation was carried out in the same manner as in Example 1, except that no epoxide of 1,2-difluoroethylene was added and only 500 mol ppm of oxygen was added in advance to 1,2-difluoroethylene. The tube was removed from the thermostatic chamber and the gas was analyzed, revealing that 67 ppm by mass of hydrogen fluoride relative to 1,2-difluoroethylene had been produced.

[0053] Example 4 Evaluation was carried out in the same manner as in Example 1, except that 125 ppm by mass of 1,2-difluoroethylene epoxide, 500 ppm by mole of oxygen, and 200 ppm by mass of water were added in advance relative to the 1,2-difluoroethylene. The tube was removed from the thermostatic chamber and the gas was analyzed, revealing that 56 ppm by mass of hydrogen fluoride relative to the 1,2-difluoroethylene had been produced.

[0054] Example 5 Evaluation was carried out in the same manner as in Example 1, except that 1,1,2-trifluoroethylene was used instead of 1,2-difluoroethylene, and 50 ppm by mass of 1,1,2-trifluoroethylene epoxide and 100 ppm by mole of oxygen were added in advance relative to the 1,1,2-trifluoroethylene. The tube was removed from the thermostatic chamber and the gas was analyzed, revealing that 5 ppm by mass of hydrogen fluoride relative to the 1,1,2-trifluoroethylene had been produced.

[0055] (Comparative Example 2) An evaluation was carried out in the same manner as in Example 1, except that a mixed refrigerant consisting of 23 mass% of 1,2-difluoroethylene and 77 mass% of 2,3,3,3-tetrafluoropropene was used instead of 1,2-difluoroethylene, and 500 mol ppm of oxygen was added beforehand. The tube was removed from the thermostatic bath and the gas was analyzed, revealing that 200 mass ppm of hydrogen fluoride had been produced relative to the mixed refrigerant of 1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene.

[0056] Example 6 Evaluation was carried out in the same manner as in Example 1, except that 125 ppm by mass of 1,2-difluoroethylene epoxide, 100 ppm by mass of potassium hydrogen phthalate, and 500 ppm by mole of oxygen were added in advance relative to the 1,2-difluoroethylene. The tube was removed from the thermostatic chamber and the gas was analyzed, revealing that 32 ppm by mass of hydrogen fluoride relative to the 1,2-difluoroethylene had been produced.

[0057] Example 7 An evaluation was carried out in the same manner as in Example 1, except that a mixed refrigerant consisting of 23 mass% of 1,2-difluoroethylene and 77 mass% of 2,3,3,3-tetrafluoropropene was used instead of 1,2-difluoroethylene, and 30 mass ppm of 1,2-difluoroethylene epoxide and 500 mol ppm of oxygen were added beforehand to the mixed refrigerant. The tube was removed from the thermostatic bath and the gas was analyzed, revealing that 160 mass ppm of hydrogen fluoride had been produced in the mixed refrigerant of 1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene.

[0058] Example 8 An evaluation was performed in the same manner as in Example 1, except that a mixed refrigerant consisting of 23 mass% of 1,2-difluoroethylene and 77 mass% of 2,3,3,3-tetrafluoropropene was used instead of 1,2-difluoroethylene, and 30 mass ppm of 1,2-difluoroethylene epoxide, 100 mass ppm of potassium hydrogen phthalate, and 500 mol ppm of oxygen were added beforehand to the mixed refrigerant. The tube was removed from the thermostatic bath and the gas was analyzed, revealing that 5 mass ppm of hydrogen fluoride had been generated in the mixed refrigerant of 1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene.

[0059] [Table 1]

Claims

1. It contains fluoroethylene and an epoxide of the fluoroethylene having 2 carbon atoms, The composition, wherein the content of the epoxide is 70 ppm by mass or more and 50,000 ppm by mass or less based on the mass of the fluoroethylene.

2. 2. The composition of claim 1, wherein the fluoroethylene has two or more fluorine atoms.

3. 3. The composition according to claim 1, wherein the oxygen content is 1 to 5000 mole ppm based on the mass of the fluoroethylene.

4. 3. The composition according to claim 1, wherein the water content is 0.1 to 100 ppm by mass based on the mass of the fluoroethylene.

5. 3. The composition of claim 1 or 2, which is a heat transfer medium, a blowing agent, or a propellant.

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