Refrigerator oil and heat pump comprising same

Abstract

A refrigerator oil according to exemplary embodiments of the present disclosure includes an amine-based phosphate compound. A heat pump according to exemplary embodiments of the present disclosure includes a refrigerant including trifluoroiodomethane (R-131I1) and the refrigerator oil.

Description

Refrigerant oil and heat pump containing the same

[0001] The present disclosure relates to refrigerant oil and a heat pump including the same.

[0002]

[0003] Recently, the types of heat pumps used indoors and outdoors have diversified, and the development of electric vehicles and other technologies has led to a demand for miniaturized heat pumps. Heat pumps are equipped with a refrigerant circulation system that includes a compressor, condenser, expansion device, and evaporator. A refrigerant circulation system utilizes the phenomenon of heat being taken from the surroundings when a liquid vaporizes. The cycle repeats, including compression and temperature increase of the vaporized refrigerant in the compressor, liquefaction of the refrigerant through heat-radiating condensation in the condenser, depressurization and expansion in the expansion device, and vaporization of the refrigerant in the evaporator.

[0004] In addition to refrigerant, the refrigerant circulation system is filled with refrigerant oil to lubricate the compressor's sliding parts. Refrigerant oil is designed to achieve the desired performance when charged to the refrigerant circulation system. However, compatibility with the refrigerant becomes crucial. For example, refrigerant oil with poor compatibility with the refrigerant may not be compatible with the refrigerant when circulated within the refrigerant circulation system, potentially preventing it from reaching the compressor's sliding parts, leading to concerns about deterioration in lubrication.

[0005] To better meet these performance requirements, refrigerating lubricants primarily composed of oxygen-containing organic compounds, such as vinyl ether compounds and polyoxyalkylene glycols, are commonly used for HFC refrigerants. To further enhance the stability and lubricating performance of refrigerating lubricants primarily composed of oxygen-containing organic compounds, various additives are typically added.

[0006]

[0007] An object of the present disclosure is to provide a refrigerant oil having improved chemical stability at high temperatures and / or high pressures.

[0008] One object of the present disclosure is to provide a heat pump including a refrigerant oil having improved chemical stability at high temperatures and / or high pressures.

[0009]

[0010] Refrigerating oil according to exemplary embodiments of the present disclosure comprises an amine phosphate compound represented by the following chemical formula 1.

[0011] [Chemical Formula 1]

[0012]

[0013] In chemical formula 1, R 1 An alkyl group having 10 to 30 carbon atoms, R 2 and R 3 are each independently hydrogen or an alkyl group having 1 to 20 carbon atoms, and x is 1 or 2.

[0014] In exemplary embodiments, R 1 It may be an alkyl group having 10 to 20 carbon atoms.

[0015] In exemplary embodiments, R 2 and R 3 Each may independently be hydrogen or an alkyl group having 1 to 10 carbon atoms.

[0016] In exemplary embodiments, R 1 is a branched alkyl group having 10 to 15 carbon atoms, and R 2 and R 3 Each may independently be hydrogen or an alkyl group having 5 to 10 carbon atoms.

[0017] In exemplary embodiments, R 1 is a tertiary alkyl group having 10 to 15 carbon atoms, and R 2 and R 3Each may independently be hydrogen or an alkyl group having 1 to 5 carbon atoms.

[0018] In exemplary embodiments, the refrigerant oil may further comprise an epoxy-based acid scavenger.

[0019] In exemplary embodiments, the acid scavenger may comprise 2-ethylhexyl glycidyl ether.

[0020] In exemplary embodiments, the refrigerant oil may further include a lubricant.

[0021] In exemplary embodiments, the lubricant may comprise a polyol ester.

[0022] A heat pump according to exemplary embodiments of the present disclosure includes a refrigerant comprising trifluoroiodomethane (R-13I1) and the refrigerating oil.

[0023]

[0024] Refrigerating oil according to exemplary embodiments of the present disclosure may have improved chemical stability at high temperatures and / or high pressures.

[0025] Heat pumps according to exemplary embodiments of the present disclosure may have improved chemical stability at high temperatures and / or high pressures.

[0026] The refrigerant oil of the present disclosure can be used in eco-friendly heat pumps and the like that use a refrigerant including trifluoroiodomethane (R-13I1) to suppress air pollution and greenhouse gas emissions and prevent climate change.

[0027]

[0028] Figures 1 and 2 are schematic diagrams showing the flow of refrigerant for heat exchange in a cooling mode or a heating mode of a heat exchanger according to one embodiment, respectively.

[0029] Figures 3 to 7 are photographs showing the ASHRAE 97 evaluation of Experimental Example 2 performed on the refrigeration oils of Example 1, Example 4, and Comparative Examples 1 to 3, respectively.

[0030]

[0031] According to embodiments of the present disclosure, a refrigerant oil comprising an amine-based phosphate compound is provided.

[0032] As the above refrigerant oil contains an amine-based phosphate compound, the chemical stability of the refrigerant at high temperature and / or high pressure can be improved.

[0033] Below, the present disclosure will be described in detail. However, this is merely exemplary and the present disclosure is not limited to the specific embodiments described as examples.

[0034] The term "organic group" as used herein may be a substituent containing only carbon and hydrogen, or containing one or more heteroatoms and containing carbon and hydrogen.

[0035] The term "heteroatom" as used herein may be an atom other than carbon and / or hydrogen. For example, the heteroatom may be nitrogen (N), oxygen (O), phosphorus (P), sulfur (S), etc.

[0036] The term "substituted" as used in the present disclosure may mean that at least one of the hydrogen atoms of the compound is substituted with a substituent such as a halogen group, a hydroxy group, a heteroalkyl group, a heterocycloalkyl group, a heteroaryl group, an amine group, a nitrile group, a nitro group, or a silyl group.

[0037] The term “unsubstituted” as used herein may mean that all hydrogen atoms of a compound are unsubstituted.

[0038] The term “alkyl group” as used in this disclosure may mean a straight or branched chain alkyl group having 1 to 10 carbon atoms, unless otherwise defined in the relevant part.

[0039] The term "cycloalkyl group" as used in this disclosure may mean a functional group in which one hydrogen atom is removed from a cycloalkane having 3 to 10 carbon atoms, unless otherwise defined in the relevant part.

[0040] The term "aryl group" used in the present disclosure may mean a functional group in which one hydrogen atom is removed from an aromatic hydrocarbon having 6 to 10 carbon atoms, unless otherwise defined in the relevant part.

[0041] Refrigerating oil according to exemplary embodiments of the present disclosure comprises an amine phosphate compound. The amine phosphate compound comprises a compound represented by the following chemical formula 1.

[0042] [Chemical Formula 1]

[0043]

[0044] In chemical formula 1, R 1 It may be an alkyl group having 10 to 30 carbon atoms, or an alkyl group having 10 to 25 carbon atoms, or an alkyl group having 10 to 20 carbon atoms.

[0045] In chemical formula 1, R 2 and R 3 Each of them can independently be hydrogen or an alkyl group having 1 to 20 carbon atoms. The alkyl group can be an alkyl group having 1 to 15 carbon atoms or an alkyl group having 1 to 10 carbon atoms.

[0046] In chemical formula 1, x can be 1 or 2.

[0047] In exemplary embodiments, the amine-based phosphate compound may function as a stabilizer. Refrigerating oil may be used with a refrigerant in a heat exchange system (e.g., a heat pump), and the amine-based phosphate compound may prevent metal corrosion due to decomposition of the refrigerant or refrigerating oil during system operation. Since the refrigerating oil includes an amine-based phosphate compound having at least 10 carbon atoms, its chemical stability at high temperatures and / or high pressures may be improved.

[0048] In exemplary embodiments, the refrigerant oil may be used with a refrigerant including trifluoroiodomethane (R-13I1). Trifluoroiodomethane (R-13I1) is a type of hydrofluorocarbon (HFC) refrigerant, has an ozone depletion potential (ODP) of 0, and a global warming potential (GWP) of less than 5. By including trifluoroiodomethane (R-13I1) in the refrigerant, environmental friendliness may be improved.

[0049] Due to its reactivity, trifluoroiodomethane (R-13I1) can react with moisture to produce acid. This can lead to oxidation of the refrigerant or refrigeration oil, discoloration of the refrigeration oil, sludge formation, and metal corrosion. Furthermore, the formation of acid can accelerate the decomposition of trifluoroiodomethane (R-13I1).

[0050] To prevent corrosion of metals due to decomposition of trifluoroiodomethane (R-13I1), the refrigerating oil may contain a stabilizer.

[0051] In exemplary embodiments, the amine phosphate compound may be present in an amount of 0.5 wt% to 3 wt%, or 0.5 wt% to 2 wt%, or 1 wt% to 2 wt% of the total weight of the refrigerating oil. When the amine phosphate compound is present in an amount of 3 wt% or less of the total weight of the refrigerating oil, the initial total acid number (TAN) of the refrigerating oil may be prevented from becoming excessively high, thereby further improving the chemical stability of the refrigerating oil.

[0052] In exemplary embodiments, R 1 It may be a branched alkyl group having 10 to 30 carbon atoms, a branched alkyl group having 10 to 25 carbon atoms, or a branched alkyl group having 10 to 20 carbon atoms. Accordingly, the chemical stability at high temperature and / or high pressure may be further improved.

[0053] In exemplary embodiments, R in formula 1 1 is a branched alkyl group having 10 to 15 carbon atoms, and R 2 and R 3 Each of which may independently be hydrogen or an alkyl group having 5 to 10 carbon atoms. However, R 2 and R 3 It can't all be hydrogen.

[0054] For example, in chemical formula 1, R 1 is a branched alkyl group having 11 to 14 carbon atoms, and R 2 and R 3 Each can independently be a hydrogen or a hexyl group. However, R 2 and R 3 It can't all be hydrogen.

[0055] In exemplary embodiments, R in formula 1 1 is a tertiary alkyl group having 10 to 15 carbon atoms, and R 2 and R3 Each may independently be hydrogen or an alkyl group having 1 to 5 carbon atoms.

[0056] In exemplary embodiments, R in formula 1 1 is a tertiary alkyl group having 12 to 14 carbon atoms, and R 2 and R 3 may be a butyl group.

[0057] In exemplary embodiments, the refrigerating oil may further include an acid scavenger. This can prevent discoloration of the refrigerating oil, sludge formation, metal corrosion, and other problems caused by oxidation of the refrigerant or refrigerating oil by removing the acid generated by the decomposition of trifluoroiodomethane (R-13I1). This can further improve chemical stability at high temperatures and / or high pressures.

[0058] In exemplary embodiments, the acid scavenger may include a phenyl glycidyl ether, an alkyl glycidyl ether, an alkylene glycol glycidyl ether, a phenyl glycidyl ester, an alkyl glycidyl ester, an alkenyl glycidyl ester, a cyclohexene oxide, an α-olefin oxide, an epoxy compound, a silane compound, or the like.

[0059] In exemplary embodiments, the acid scavenger may comprise an epoxy-based acid scavenger.

[0060] For example, the epoxy acid scavenger may include 2-ethylhexyl glycidyl ether. As the epoxy acid scavenger further includes a glycidyl functional group, the acid scavenging ability may be further improved.

[0061] In exemplary embodiments, the refrigerating oil may further include a lubricant. For example, the lubricant may include paraffin, naphthene, aromatic hydrocarbon, benzene or naphthalene substituted or unsubstituted with linear and branched alkyl groups, polyester, polyol ester, polyvinyl ether, and the like. For example, the lubricant may include alkylated naphthalene. The alkylated naphthalene may be monoalkyl naphthalene, dialkyl naphthalene, trialkyl naphthalene, tetraalkyl naphthalene, or a mixture thereof.

[0062] For example, the lubricant may comprise a polyol ester.

[0063] The lubricant may be from 70 wt% to 99 wt%, or from 80 wt% to 98.5 wt%, or from 90 wt% to 98 wt%, or from 91 wt% to 97.5 wt% of the total weight of the refrigerating oil.

[0064] Refrigerating oil according to exemplary embodiments may further include an antioxidant, an anti-foaming agent, a load-bearing additive, a chlorine scavenger, a detergent dispersant, a viscosity index improver, an oiliness agent, a rust inhibitor, a pour point depressant, an extreme pressure additive, and the like.

[0065] For example, the antioxidant may be a phenolic or amineic antioxidant. The phenolic antioxidant may be 2,6-di-tert-butyl-4-methylphenol (DBPC), 2,6-di-tert-butyl-4-ethylphenol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,4-dimethyl-6-tert-butylphenol, 2,6-di-tert-butylphenol, etc. The above amine antioxidant may be N,N'-diisopropyl-p-phenylenediamine, N,N'-di-sec-butyl-p-phenylenediamine, phenyl-α-naphthylamine, N,N'-diphenyl-p-phenylenediamine, etc.

[0066] For example, the foaming agent may be a homopolymer or copolymer of acrylic ester.

[0067] For example, the extreme pressure additive may be an extreme pressure additive of an organosulfur compound, an extreme pressure additive of a phosphorothioate ester, an ester-based extreme pressure additive, an organochlorine-based extreme pressure additive, an organofluorine-based extreme pressure additive, an alcohol-based extreme pressure additive, an extreme pressure additive of a metal compound, etc. The extreme pressure additive of the organosulfur compound may be a monosulfide, a polysulfide, a sulfoxide, a sulfone, a thiosulfinate, a sulfurized oil, a thiocarbonate, a thiophene, a thiazole, a methanesulfonate, etc. The ester-based extreme pressure additive may be a higher fatty acid, a hydroxyaryl fatty acid, a polyol ester, an acrylate, etc. The extreme pressure additive of the organochlorine-based may be a chlorinated hydrocarbon or a chlorinated carboxylic acid derivative, etc. The above-mentioned organic fluorine-based extreme pressure additive may be a fluorinated aliphatic carboxylic acid, a fluoroethylene resin, a fluoroalkyl polysiloxane, a fluorinated graphite, etc. The above-mentioned extreme pressure additive of the metal compound may be a naphthenate (such as lead naphthenic acid), a fatty acid salt (such as lead fatty acid salt), a thiophosphate (such as zinc dialkyldithiophosphate), a thiocarbamate, an organic molybdenum compound, an organic tin compound, an organic germanium compound, etc.

[0068] Figures 1 and 2 are schematic diagrams showing the flow of refrigerant for heat exchange in a cooling mode or a heating mode of a heat exchanger according to one embodiment, respectively.

[0069] The direction of the arrows in Figures 1 and 2 is intended to indicate the flow of refrigerant.

[0070] Referring to Figure 1, in cooling mode, the refrigerant is compressed through the compressor, bypasses the internal condenser and expansion valve (heating) in sequence, releases heat from the external condenser, then expands in the expansion valve (cooling) and reabsorbs heat through the evaporator.

[0071] Referring to Figure 2, in heating mode, the refrigerant is compressed through the compressor, releases heat from the internal condenser, expands in the expansion valve (heating), absorbs heat from the external condenser, and then absorbs additional heat through the cooler.

[0072] A heat pump according to exemplary embodiments of the present disclosure includes a refrigerant comprising trifluoroiodomethane (R-13I1) and the refrigerating oil. Accordingly, the heat pump can have improved refrigeration performance while being environmentally friendly and stable.

[0073] The above heat pump may include a compressor, a condenser, an expansion valve, and an evaporator. In the compressor, the above-described refrigerant may be compressed to a high temperature and high pressure state, and in the expansion valve, the above-described refrigerant may be expanded to a low temperature and low pressure state.

[0074] For example, the refrigerant described above can release or absorb heat while circulating through a compressor, a condenser, an expansion valve, and an evaporator within the heat pump. The refrigerant can be maintained in a high-temperature and high-pressure gaseous state in the compressor. The refrigerant can be liquefied into a liquid state by releasing heat in the condenser. The refrigerant can be maintained in a low-temperature and low-pressure liquid, or a liquid and gas mixture state, in the expansion valve. The refrigerant can absorb heat in the evaporator and vaporize into a gaseous state.

[0075] In some embodiments, the coefficient of performance (COP) of the heat pump may be 1 to 10. The coefficient of performance (COP) refers to the ratio of the amount of heat effectively obtained to the amount of work input when operating the heat pump.

[0076] A high-efficiency heat pump having a performance coefficient within the above range can be provided using the above-described refrigerant.

[0077] According to exemplary embodiments, the refrigerant including trifluoroiodomethane (R-13I1) may further include a natural refrigerant, a hydrofluorocarbon (HFC) refrigerant, a hydrofluoroolefin (HFO) refrigerant, a hydrochlorofluorocarbon (HCFC) refrigerant, etc.

[0078] The above natural refrigerants may include methane (R-50), ammonia (R-717), carbon dioxide (R-744), ethane (R-170), propane (R-290), propylene (R-1270), isobutane (R-600a), dimethyl ether, isopentane, pentane, etc.

[0079] The above hydrofluorocarbon (HFC) refrigerants include difluoromethane (R-32), 1,1-difluoroethane (R-152a), pentafluoroethane (R-125), 1,1,1,2-tetrafluoroethane (R-134a), 1,1,1-trifluoroethane (R-143a), trifluoromethyl methyl ether (RE143a), trifluoromethane (R-23), fluoroethane (R-161), octafluoropropane (R-218), 1,1,1,2,3,3,3-heptafluoropropane (R-227ea), 1,1,1,2,3,3-hexafluoropropane (R-236ea), 1,1,1,3,3,3-hexafluoropropane (R-236fa), It may include 1,1,1,3,3-pentafluoropropane (R-245fa), octafluorocyclobutane (RC318), 1,1,1,3,3-pentafluorobutane (R-365mfc), etc.

[0080] The above hydrofluoroolefin (HFO) refrigerant may include 1,1,2-trifluoroethylene (R-1123), 1-chloro-2,3,3,3-tetrafluoropropene (R1224yd(Z)), 2,3,3,3-tetrafluoropropene (R-1234yf), 1,3,3,3-tetrafluoropropene (R-1234ze), 1,2,3,3-tetrafluoropropene (R-1234ye), 3,3,3-trifluoropropene (R-1243zf), 1,1-difluoroethylene (R-1132a), 1,2,3,3,3-pentafluoropropene (R-1225ye), etc.

[0081] The above hydrochlorofluorocarbon (HCFC) refrigerants may include difluorochloromethane (R-22), chlorotetrafluoroethane (R-124), 1-chloro-1,1-difluoroethane (R-142b), etc.

[0082] Hereinafter, examples are presented to help understand the present disclosure, but these examples are only illustrative of the present disclosure and do not limit the scope of the appended claims. It will be apparent to those skilled in the art that various changes and modifications to the examples are possible within the scope and technical idea of ​​the present disclosure, and it is also natural that such changes and modifications fall within the scope of the appended claims.

[0083] The refrigerating oil according to the first aspect of the present disclosure comprises an amine-based phosphate compound represented by the following chemical formula 1.

[0084] [Chemical Formula 1]

[0085]

[0086] In chemical formula 1, R 1 An alkyl group having 10 to 30 carbon atoms, R 2 and R 3 are each independently hydrogen or an alkyl group having 1 to 20 carbon atoms, and x is 1 or 2.

[0087] In the first aspect above, according to the second aspect R 1It may be an alkyl group having 10 to 20 carbon atoms.

[0088] In the first aspect or the second aspect, according to the third aspect, R 2 and R 3 Each may independently be hydrogen or an alkyl group having 1 to 10 carbon atoms.

[0089] In any one of the first to third aspects, according to the fourth aspect, R 1 is a branched alkyl group having 10 to 15 carbon atoms, and R 2 and R 3 Each may independently be hydrogen or an alkyl group having 5 to 10 carbon atoms.

[0090] In any one of the first to fourth aspects, according to the fifth aspect, R 1 is a tertiary alkyl group having 10 to 15 carbon atoms, and R 2 and R 3 Each may independently be hydrogen or an alkyl group having 1 to 5 carbon atoms.

[0091] In any one of the first to fifth aspects, the sixth aspect may further include an epoxy-based acid scavenger.

[0092] In any one of the first to sixth aspects, according to the seventh aspect, the acid scavenger may include 2-ethylhexyl glycidyl ether.

[0093] In any one of the first to seventh aspects, a lubricant may be further included according to the eighth aspect.

[0094] In the eighth aspect, according to the ninth aspect, the lubricant may include a polyol ester.

[0095] A heat pump according to a tenth aspect of the present disclosure comprises a refrigerant comprising trifluoroiodomethane (R-13I1) and a refrigerating oil according to any one of the first to ninth aspects.

[0096] Examples and Comparative Examples

[0097] Refrigerating oils of examples and comparative examples were manufactured with the compositions described in Table 1 below.

[0098] Classification POE (wt%) Alkylated naphthalene (wt%) Acid scavenger (wt%) Stabilizer component content (wt%) Example 19521.5A11.5 Example 29621.5A10.5 Example 391.521.5A15 Example 49521.5A21.5 Example 59621.5A20.5 Example 691.521.5A25 Comparative Example 196.521.5--Comparative Example 29521.5B11.5 Comparative Example 39521.5B21.5

[0099] * POE: (Synative ES 4068, BASF)

[0100] * alkylated naphthalene (Synesstic 5, Exxon mobil company)

[0101] * Acid scavenger: 2-ethylhexyl glycidyl ether (CAS 2461-15-6)

[0102] * A1: Amines, C11-14-branched alkyl, monohexyl and dihexyl phosphates Phenol (CAS 80939-62-4, Lanxess)

[0103] * A2: Amines, C12-14-tert-alkyl, di-Bu phosphatesisopropylated (CAS 103213-64-5, Lanxess)

[0104] * B1: Octylamine (CAS 111-86-4, Aldrich)

[0105] * B2: Dioctylamine (CAS 1120-48-5, Aldrich)

[0106]

[0107] Experimental Example 1: Load-bearing capacity (FALEX LOAD) evaluation

[0108] The load-bearing capacity of the refrigerating oils of the examples and comparative examples was evaluated using the ASTM D3233 method using Falex Pin & Vee Block (FALEX).

[0109] Experimental Example 2: ASHRAE 97 Evaluation

[0110] Refrigerating oil, CF3I, copper (Cu) catalyst, aluminum (Al) catalyst, and iron (Fe) catalyst of the examples and comparative examples were placed in a sealed tube, and the following evaluation was performed after exposure to an environment of 150°C for 14 days.

[0111] 1) ASTM color measurement

[0112] LICO 500 - Color was measured using the ASTM D1500 method using a spectral colorimeter (HACH LANGE).

[0113] Figures 3 to 7 are photographs showing the ASHRAE 97 evaluation of Experimental Example 2 performed on the refrigeration oils of Example 1, Example 4, and Comparative Examples 1 to 3, respectively.

[0114] The evaluation results of Experimental Examples 1 and 2 for the refrigerating oils of Examples 1 to 6 and Comparative Examples 1 to 3 are shown in Table 2 below.

[0115] Refrigerant Oil FALEX LOAD (lbf) ASTM color after ASHRAE 97 evaluation Example 115006 Example 212505 Example 315007.5 Example 415004 Example 512503 Example 615006 Comparative Example 17508 Comparative Example 27508 Comparative Example 37508

[0116] Referring to FIGS. 3 to 7, the refrigerating oils of Examples 1 and 4 showed less color change and thus had better chemical stability at high temperatures than the refrigerating oils of the comparative examples.

[0117] Referring to Table 2, the FALEX LOAD of the refrigeration oils of Examples 1 to 6 was 1250 lbf or more, while the FALEX LOAD of the refrigeration oils of Comparative Examples 1 to 3 was 750 lbf, indicating that the load-bearing properties of the refrigeration oils of the Examples containing amine-based phosphate compounds were better.

[0118] In the case of the refrigerating oils of the examples, the ASTM color was 7.5 or lower, whereas in the case of the refrigerating oils of the comparative examples, the ASTM color was 8, which was the darkest.

[0119] Accordingly, the examples using amine phosphates having 10 or more carbon atoms as stabilizers had better chemical stability at high temperatures.

Claims

1. Refrigerating oil comprising an amine phosphate compound represented by the following chemical formula 1: [Chemical Formula 1] (In chemical formula 1, R 1 An alkyl group having 10 to 30 carbon atoms, R 2 and R 3 are each independently hydrogen or an alkyl group having 1 to 20 carbon atoms, and x is 1 or 2).

2. In claim 1, R 1 Refrigerating oil, which is an alkyl group having 10 to 20 carbon atoms.

3. In claim 1, R 2 and R 3 Refrigerating oil, each independently hydrogen or an alkyl group having 1 to 10 carbon atoms.

4. In claim 1, R 1 is a branched alkyl group having 10 to 15 carbon atoms, and R 2 and R 3 Refrigerating oil, each independently hydrogen or an alkyl group having 5 to 10 carbon atoms.

5. In claim 1, R 1 is a tertiary alkyl group having 10 to 15 carbon atoms, and R 2 and R 3 Refrigerating oil, each independently hydrogen or an alkyl group having 1 to 5 carbon atoms.

6. A refrigerating oil according to claim 1, further comprising an epoxy acid scavenger.

7. A refrigerating oil according to claim 1, wherein the acid scavenger comprises 2-ethylhexyl glycidyl ether.

8. Refrigerating oil according to claim 1, further comprising a lubricant.

9. In claim 8, the lubricant is a refrigerating oil comprising a polyol ester.

10. Refrigerants containing trifluoroiodomethane (R-13I1); and A heat pump comprising the refrigerant oil of claim 1.

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