Compositions containing difluoromethane, tetrafluoropropene, and carbon dioxide, and uses thereof

Abstract

To provide lower-GWP replacement refrigerants.SOLUTION: In the present invention, refrigerant compositions are disclosed. The compositions comprise a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2. The compositions are useful in processes to produce cooling and heating, in methods for replacing refrigerant R-410A, and in refrigeration, air-conditioning or heat pump systems. These inventive compositions match cooling capacity for R-410A within ±10% with GWP less than 400 or less than 300.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present disclosure relates to compositions for use in refrigeration, air conditioning and heat pump systems. The compositions of the present invention are useful in methods of producing cooling and heating and in methods of replacing refrigerants, as well as in refrigeration, air conditioning and heat pump equipment. [Background technology]

[0002] The refrigeration industry has been working for the past few decades to find replacements for the ozone-depleting chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) that are being phased out as a result of the Montreal Protocol. The solution for most refrigerant producers has been the commercialization of hydrofluorocarbon (HFC) refrigerants. These HFC refrigerants in widespread use today, including HFC-134a, R-32, and R-410A among others, are not subject to the current regulatory phase-out as a result of the original Montreal Protocol because they have zero ozone depletion potential. With the implementation of the Kigali Amendment to the Montreal Protocol, there is a demand for alternative refrigerants with lower GWP. Summary of the Invention [Means for solving the problem]

[0003] It has been found that certain compositions containing difluoromethane, tetrafluoropropene and carbon dioxide have favorable properties that allow them to be used as replacements for currently available commercial refrigerants, particularly R-410A, which have relatively high GWPs. Thus, the inventors have discovered a refrigerant gas that is non-ozone depleting, has a significantly lower direct global warming potential, matches the performance of R-410A, and is therefore an environmentally sustainable replacement.

[0004] In accordance with the present invention, a composition is disclosed that includes a refrigerant composition, the refrigerant mixture consisting essentially of difluoromethane, tetrafluoropropene, and carbon dioxide.

[0005] The refrigerant compositions are useful in processes that produce cooling or heating, in methods of replacing the refrigerant R-410A, particularly in air conditioning and heat pump systems, as components of compositions that also contain non-refrigerant components (e.g., lubricants). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0006] Before going into the details of the embodiments described below, some terms will be defined or clarified.

[0007] definition As used herein, the term heat transfer fluid (also called heat transfer medium) refers to a composition used to transport heat from a heat source to a heat sink.

[0008] A heat source is defined as any space, location, object, or body to which it is desirable to add, transfer, move, or remove heat. Examples of heat sources are spaces (open or enclosed) that require refrigeration or cooling, such as supermarket refrigerators or freezer cases, refrigerated containers for transport, building spaces requiring air conditioning, industrial water coolers, or automobile passenger compartments requiring air conditioning. In some embodiments, the heat transfer composition may remain constant (i.e., do not evaporate or condense) throughout the transfer process. In other embodiments, the heat transfer composition may also be used in evaporative cooling processes.

[0009] A heat sink is defined as any space, place, thing or object that can absorb heat. A vapor compression refrigeration system is one example of such a heat sink.

[0010] A refrigerant is defined as a heat transfer fluid that undergoes a phase change from liquid to gas and back again during the cycle used to transfer heat.

[0011] A heat transfer system is a system (or equipment) used to create a heating or cooling effect in a particular space. Heat transfer systems can be mobile or stationary systems.

[0012] Examples of heat transfer systems include any type of cooling and air conditioning system, including, but not limited to, stationary heat transfer systems, air conditioners, freezers, refrigerators, heat pumps, water chillers, flooded evaporator chillers, direct expansion chillers, walk-in coolers, mobile refrigerators, mobile heat transfer systems, mobile air conditioning units, dehumidifiers, and combinations thereof.

[0013] Refrigeration capacity (also called cooling capacity) is a term that defines the change in enthalpy of the refrigerant in the evaporator per pound of refrigerant circulating, or the heat removed by the refrigerant in the evaporator per unit volume of refrigerant vapor leaving the evaporator. Cooling capacity is a measure of the ability of a refrigerant or heat transfer composition to produce cooling. Thus, the higher this capacity, the more cooling is produced. Cooling rate refers to the amount of heat removed per unit time by the refrigerant in the evaporator.

[0014] The Coefficient of Performance (COP) is the amount of heat removed divided by the energy input required to run the cycle. The higher the COP, the more energy efficient it is. COP is directly related to the Energy Efficiency Ratio (EER), which is a rating of the efficiency of a cooling or air conditioning system at a specific set of internal and external temperatures.

[0015] The term "subcooling" refers to lowering the temperature of a liquid below the saturation point of that liquid for a given pressure. The saturation point is the temperature at which the vapor is completely condensed into a liquid, whereas subcooling continues to cool the liquid to a lower temperature liquid at a given pressure. Cooling a liquid below its saturation temperature (or boiling point temperature) can increase the net cooling capacity. Subcooling thereby increases the cooling capacity and energy efficiency of the system. The amount of subcooling is the amount of cooling below the saturation temperature (in degrees).

[0016] Superheat is a term that defines how much a vapor composition is heated above its saturated vapor temperature (the temperature at which the first drop of liquid forms when the composition is cooled, also called the "dew point").

[0017] Temperature gradient (sometimes simply called "gradient") is the absolute value of the difference between the start and end temperatures of a phase change process by a refrigerant in a component of a refrigerant system, excluding any subcooling or superheating. The term can be used to describe the condensation or evaporation of a near-azeotropic or non-azeotropic composition. When referring to the temperature gradient of a refrigeration, air conditioning, or heat pump system, it is common to provide the average temperature gradient, which is the average of the temperature gradient in the evaporator and the temperature gradient in the condenser.

[0018] Net cooling effect is the amount of heat absorbed by 1 kg of refrigerant in the evaporator to produce useful cooling.

[0019] Mass flow is the amount of refrigerant (in kilograms) circulating through a cooling, heat pump, or air conditioning system at a given time.

[0020] As used herein, the term "lubricant" means any material added to a composition or compressor (and in contact with any heat transfer composition in use in any heat transfer system) that provides lubrication to the compressor to help prevent parts from seizing.

[0021] As used herein, a compatibilizer is a compound that improves the solubility of the hydrofluorocarbon of the disclosed composition in a heat transfer system lubricant. In some embodiments, the compatibilizer improves oil return to the compressor. In some embodiments, the composition is used with a system lubricant to reduce the viscosity of the oil-rich phase.

[0022] As used herein, oil return refers to the ability of a heat transfer composition to carry lubricant through a heat transfer system and return the lubricant to the compressor. That is, during use, it is not uncommon for some of the compressor lubricant to be carried away by the heat transfer composition from the compressor to other parts of the system. In such a system, if the lubricant is not efficiently returned to the compressor, the compressor will eventually fail due to lack of lubrication.

[0023] As used herein, an "ultraviolet" dye is defined as an ultraviolet fluorescent or phosphorescent composition that absorbs light in the ultraviolet or "near" ultraviolet region of the electromagnetic spectrum. The fluorescence produced by an ultraviolet fluorescent dye can be detected under ultraviolet illumination that emits at least some radiation having a wavelength in the range of 10 nanometers to about 775 nanometers.

[0024] Flammability is a term used to mean the ability of a composition to ignite and / or propagate a flame. For refrigerants and other heat transfer compositions, the lower flammability limit ("LFL") is the lowest concentration of the heat transfer composition in air that can propagate a flame through a homogeneous mixture of the composition and air under the test conditions described in ASTM (American Society of Testing and Material) E681. The upper flammability limit ("UFL") is the highest concentration of the heat transfer composition in air that can propagate a flame through a homogeneous mixture of the composition and air under the same test conditions. Also, testing under the conditions of ASTM-681 determines whether a refrigerant compound or mixture is flammable or non-flammable.

[0025] During a refrigerant leak, the lower boiling components of the mixture may leak preferentially. This may cause the composition of the system as well as the vapor leak to change over the time of the leak. This may cause a non-flammable mixture to become flammable under potential leak conditions. Also, to be classified as non-flammable by ASHRAE (American Society of Heating, Refrigeration and Air-conditioning Engineers), a refrigerant or heat transfer composition must be non-flammable not only as formulated but also under leak conditions.

[0026] Global Warming Potential (GWP) is an index for estimating the relative global warming contribution due to the atmospheric emission of one kilogram of a particular greenhouse gas compared to the emission of one kilogram of carbon dioxide. GWP can be calculated for various time horizons and indicates the effect of the atmospheric lifetime of a given gas. The GWP for a 100-year time horizon is the commonly referenced value. For mixtures, a weighted average can be calculated based on the individual GWPs for each component.

[0027] Ozone depletion potential (ODP) is a number that indicates the degree of ozone destruction caused by a substance. ODP is the ratio of a chemical's effect on the ozone compared to the effect of a similar mass of CFC-11 (fluorotrichloromethane). For this reason, CFC-11 is defined as having an ODP of 1.0. Other CFCs and HCFCs have ODPs in the range of 0.01 to 1.0. HFCs and HFOs have an ODP of 0 because they do not contain chlorine or other ozone-depleting halogens.

[0028] As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," or any other variation thereof, are intended to cover non-exclusive inclusions. For example, a composition, process, method, article, or device that includes recited elements is not necessarily limited to only those elements, but may include other elements not expressly recited or that are inherent in such composition, process, method, article, device, etc.

[0029] The transitional phrase "consisting of" excludes any unspecified element, step, or ingredient. When in a claim, such a phrase will complete the claim to include materials other than those recited, except for impurities normally accompanying the materials. When the phrase "consisting of" appears within a clause in the body of a claim rather than immediately following the preamble, the phrase is intended to limit only the elements set forth in that clause and does not exclude other elements from the claim as a whole.

[0030] The transitional phrase "consisting essentially of" is used to define a composition, method, or apparatus that includes materials, steps, features, components, or elements in addition to those literally disclosed, provided that these additionally included materials, steps, features, components, or elements do not materially affect the basic and novel characteristics of the claimed invention. The term "consisting essentially of" occupies a middle ground between "comprising" and "consisting of." Typically, the components of the refrigerant mixture and the refrigerant mixture itself may contain small amounts (e.g., less than about 0.5 weight percent in total) of impurities and / or by-products (e.g., from production of the refrigerant components or recycling of refrigerant components from other systems) that do not materially affect the novel and basic characteristics of the refrigerant mixture.

[0031] It should be readily understood that where an applicant defines an invention or a portion thereof with open-ended terms such as "comprising," the description should also be construed as describing such invention using the terms "consisting essentially of" or "consisting of" (unless otherwise expressly stated).

[0032] Additionally, the use of "a" or "an" is used to describe elements and components described herein. This is merely for convenience and to give a general sense of the scope of the invention. This description should be interpreted to include one or at least one, and the singular also includes the plural unless it is clear that a different meaning is intended.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs. Although methods and materials similar or equivalent to those described herein can be used in carrying out or testing the disclosed composition embodiments, suitable methods and materials are described below. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety, unless a specific passage is cited. In case of conflict, the present specification, including definitions, will take precedence. Furthermore, the materials, methods, and examples are merely illustrative and are not intended to be limiting.

[0034] 2,3,3,3-Tetrafluoropropene may also be referred to as HFO-1234yf, HFC-1234yf, or R-1234yf. HFO-1234yf may be made by methods known in the art, such as by dehydrofluorination of 1,1,1,2,3-pentafluoropropane (HFC-245eb) or 1,1,1,2,2-pentafluoropropane (HFC-245cb).

[0035] Difluoromethane (HFC-32 or R-32) is commercially available or can be made by methods known in the art, such as, for example, the dechlorination of methylene chloride.

[0036] Carbon dioxide (CO2) is commercially available from a number of gas suppliers or can be produced by any of a number of well-known methods.

[0037] composition The refrigeration industry is struggling to develop new refrigerant products that provide acceptable performance and environmental sustainability. New global warming regulations may impose global warming potential (GWP) limits on new refrigerant compositions. Thus, the industry needs to find low GWP, low toxicity, low ozone depletion potential (ODP) components that also provide good cooling and heating performance. R-410A (a blend of 50 weight percent HFC-32 and 50 weight percent HFC-125) has been used in air conditioning and heat pumps as a replacement for R-22 for many years, but it needs to be replaced because its GWP is too high. The compositions described herein provide such a replacement with a lower GWP than previously proposed alternative refrigerants.

[0038] In one embodiment, the refrigerant mixture has a GWP of less than or equal to 400 based on AR4 data. In another embodiment, the refrigerant mixture has a GWP of less than or equal to 300 based on AR4 data.

[0039] The present inventors have identified non-flammable compositions that provide performance characteristics that function as a replacement for R-410A in refrigeration, air conditioning, and heat pump equipment. These compositions include refrigerant mixtures consisting essentially of difluoromethane, 2,3,3,3-tetrafluoropropene, and carbon dioxide. In one embodiment, the composition comprising the refrigerant mixture consists of difluoromethane, 2,3,3,3-tetrafluoropropene, and carbon dioxide.

[0040] Identifying an alternative refrigerant with the right balance of properties required for a particular application is not an easy task. The industry has struggled to find a high capacity refrigerant with reasonable temperature gradient. In particular, a refrigerant to replace R-410A that can match the cooling capacity of R-410A with an acceptable temperature gradient and a GWP of 400 or less, or even 300 or less, is desired.

[0041] Disclosed herein are compositions comprising a refrigerant mixture for replacing R-410A consisting essentially of about 42 to about 59 weight percent difluoromethane (HFC-32), about 33 to about 53 weight percent 2,3,3,3-tetrafluoropropene (HFO-1234yf), and about 1 to about 9 weight percent carbon dioxide (CO2).

[0042] In another embodiment, the refrigerant mixture consists essentially of from about 42 to about 59 weight percent HFC-32, from about 35 to about 51 weight percent 2,3,3,3-tetrafluoropropene, and from about 2 to about 9 weight percent CO2.

[0043] In another embodiment, the refrigerant mixture consists essentially of about 42-59 weight percent HFC-32, about 37-48 weight percent 2,3,3,3-tetrafluoropropene, and about 3-9 weight percent CO2.

[0044] In another embodiment, the refrigerant mixture consists essentially of about 42-47 weight percent HFC-32, about 40-49 weight percent 2,3,3,3-tetrafluoropropene, and about 3-9 weight percent CO2.

[0045] In another embodiment, the refrigerant mixture consists essentially of about 44-47 weight percent HFC-32, about 40-49 weight percent 2,3,3,3-tetrafluoropropene, and about 5-9 weight percent CO2.

[0046] In another embodiment, the refrigerant mixture consists essentially of about 42-45 weight percent difluoromethane, about 46-49 weight percent 2,3,3,3-tetrafluoropropene, and about 6-9 weight percent CO2.

[0047] In another embodiment, the refrigerant mixture consists essentially of about 42-44 weight percent HFC-32, about 48-51 weight percent 2,3,3,3-tetrafluoropropene, and about 7-9 weight percent CO2.

[0048] In another embodiment, the refrigerant mixture consists essentially of about 43-44 weight percent HFC-32, about 48-50 weight percent 2,3,3,3-tetrafluoropropene, and about 7-8 weight percent CO2.

[0049] In another embodiment, the refrigerant mixture consists essentially of about 44 weight percent HFC-32, about 49 weight percent 2,3,3,3-tetrafluoropropene, and about 7 weight percent CO2.

[0050] In another embodiment, the refrigerant mixture consists essentially of from about 47 to about 59 weight percent difluoromethane, from about 37 to about 49 weight percent 2,3,3,3-tetrafluoropropene, and from about 3 to about 8 weight percent carbon dioxide.

[0051] In another embodiment, the refrigerant mixture consists essentially of from about 52 to about 59 weight percent difluoromethane, from about 37 to about 42 weight percent 2,3,3,3-tetrafluoropropene, and from about 3 to about 6 weight percent carbon dioxide.

[0052] In another embodiment, the refrigerant mixture consists essentially of about 57 to about 59 weight percent difluoromethane, about 37 to about 39 weight percent 2,3,3,3-tetrafluoropropene, and about 3 to about 5 weight percent carbon dioxide.

[0053] In another embodiment, the refrigerant mixture consists essentially of about 58 weight percent difluoromethane, about 38 weight percent 2,3,3,3-tetrafluoropropene, and about 4 weight percent carbon dioxide.

[0054] In any of the above embodiments, the total of the refrigerant mixture must, of course, equal 100%.

[0055] In one embodiment, the refrigerant mixture provides a replacement for R-410A with a cooling capacity within 10% of that of R-410A. In another embodiment, the refrigerant mixture provides a replacement for R-410A with a cooling capacity within 5% of that of R-410A. In another embodiment, the refrigerant mixture provides a replacement for R-410A with a cooling capacity within 2% of that of R-410A. In another embodiment, the refrigerant mixture provides a replacement for R-410A with a cooling capacity that matches or improves on that of R-410A.

[0056] In one embodiment, the refrigerant mixture provides a replacement for R-410A with an average temperature gradient in the heat exchanger of less than 8.0° C. In one embodiment, the refrigerant mixture provides a replacement for R-410A with an average temperature gradient in the heat exchanger of less than 7.5° C.

[0057] Particularly interesting replacements for R-410A include compositions such as those shown in Table A.

[0058] [Table 1]

[0059] In some embodiments, the compositions of the present disclosure may optionally include non-refrigerant components in addition to difluoromethane, 2,3,3,3-tetrafluoropropene, and carbon dioxide. Thus, disclosed herein are compositions that include a refrigerant mixture consisting essentially of difluoromethane, 2,3,3,3-tetrafluoropropene, and carbon dioxide, further including one or more optional non-refrigerant components selected from the group consisting of lubricants, dyes (including UV dyes), solubilizers, compatibilizers, stabilizers, tracers, antiwear agents, extreme pressure additives, corrosion and oxidation inhibitors, metal surface energy reducers, metal surface deactivators, free radical scavengers, foam control agents, viscosity index improvers, pour point depressants, detergents, viscosity modifiers, and mixtures thereof. In some embodiments, the optional non-refrigerant components may also be referred to as additives. Indeed, many of these optional non-refrigerant components may fit one or more of these classifications and have qualities that themselves aid in achieving one or more performance characteristics.

[0060] In some embodiments, one or more non-refrigerant components are present in a small amount relative to the total composition. In some embodiments, the concentration of additive(s) in the disclosed compositions is from less than about 0.1 weight percent to as much as about 5 weight percent of the total composition. In some embodiments of the present invention, the additive is present in the compositions disclosed herein in an amount of about 0.1 weight percent to about 5 weight percent, or about 0.1 weight percent to about 3.5 weight percent, relative to the total composition. The additive component(s) selected for the compositions of the present disclosure are selected based on practicality and / or requirements of the individual equipment components or systems.

[0061] In one embodiment, the lubricant is selected from the group consisting of mineral oil, alkylbenzenes, polyol esters, polyalkylene glycols, polyvinyl ethers, polycarbonates, perfluoropolyethers, silicones, silicate esters, phosphate esters, paraffins, naphthenes, polyalpha-olefins, and combinations thereof.

[0062] The lubricant disclosed herein may be a commercially available lubricant. For example, the lubricant may be a paraffinic mineral oil sold by BVA Oil under the trade name BVM 100N, naphthenic mineral oil sold by Crompton Co. under the trade name Suniso® 1GS, Suniso® 3GS, and Suniso® 5GS, naphthenic mineral oil sold by Pennzoil under the trade name Sontex® 372LT, naphthenic mineral oil sold by Calumet Lubricants under the trade name Calumet® RO-30, linear alkyl benzene sold by Shrieve Chemicals under the trade name Zerol® 75, Zerol® 150, and Zerol® 500, branched alkyl benzene sold by Nippon Oil under the trade name HAB22, polyol ester (POE) sold by Castrol, United Kingdom under the trade name Castrol® 100, Dow (Dow Oil), or similar lubricant. and polyalkylene glycols (PAGs), such as RL-488A manufactured by Epson Corporation, Midland, Michigan, as well as mixtures thereof (meaning any mixture of the lubricants disclosed in this section).

[0063] In compositions of the present invention that include a lubricant, the lubricant is present in an amount less than 40.0 weight percent of the total composition. In other embodiments, the amount of lubricant is less than 20 weight percent of the total composition. In other embodiments, the amount of lubricant is less than 10 weight percent of the total composition. In other embodiments, the approximate amount of lubricant is between about 0.1 weight percent and 5.0 weight percent of the total composition.

[0064] Notwithstanding the above weight ratios of the compositions disclosed herein, it is understood that in some heat transfer systems, additional lubricant may be obtained from one or more equipment components of such heat transfer systems while the compositions are in use. For example, in some refrigeration, air conditioning and heat pump systems, lubricant may be filled into the compressor and / or compressor lubrication sump. Such lubricant is present in the refrigerant of such systems in addition to any lubricant additives. During use, when in the compressor, the refrigerant composition may pick up an amount of equipment lubricant, changing the refrigerant-lubricant composition from the starting ratio.

[0065] The non-refrigerant components used with the compositions of the present invention may include at least one dye. The dye may be at least one ultra-violet (UV) dye. The UV dye may be a fluorescent dye. The fluorescent dye may be selected from the group consisting of naphthalimide, perylene, coumarin, anthracene, phenanthracene, xanthene, thioxanthene, naphthoxanthene, fluorescein, and derivatives of such dyes, and combinations thereof (meaning any mixture of the dyes or derivatives thereof disclosed in this section).

[0066] In some embodiments, the disclosed compositions contain from about 0.001 weight percent to about 1.0 weight percent of a UV dye, in other embodiments the UV dye is present in an amount from about 0.005 weight percent to about 0.5 weight percent, and in other embodiments the UV dye is present in an amount from 0.01 weight percent to about 0.25 weight percent of the total composition.

[0067] UV dyes are useful components in detecting leaks of compositions because the fluorescence of the dye can be observed at or near the point of the leak in an appliance (e.g., a cooling unit, air conditioner, or heat pump). The UV emission (e.g., fluorescence from the dye) may be observed under UV light. Thus, if a composition containing such a UV dye leaks from a given point in the appliance, the fluorescence can be detected at or near the point of the leak.

[0068] Another non-refrigerant component that may be used with the compositions of the present invention may include at least one solubilizing agent selected to improve the solubility of one or more dyes in the compositions of the present disclosure. In some embodiments, the weight ratio of dye to solubilizing agent ranges from about 99:1 to about 1:1. The solubilizing agent may include at least one compound selected from the group consisting of hydrocarbons, hydrocarbon ethers, polyoxyalkylene glycol ethers (e.g., dipropylene glycol dimethyl ether), amides, nitriles, ketones, chlorocarbons (e.g., methylene chloride, trichloroethylene, chloroform, or mixtures thereof), esters, lactones, aromatic ethers, fluoroethers, and 1,1,1-trifluoroalkanes and mixtures thereof (meaning any mixture of solubilizing agents disclosed in this section).

[0069] In some embodiments, the non-refrigerant component includes at least one compatibilizer to improve compatibility of the disclosed composition with one or more lubricants. The compatibilizer may be selected from the group consisting of hydrocarbons, hydrocarbon ethers, polyoxyalkylene glycol ethers (e.g., dipropylene glycol dimethyl ether), amides, nitriles, ketones, chlorocarbons (e.g., methylene chloride, trichloroethylene, chloroform, or mixtures thereof), esters, lactones, aromatic ethers, fluoroethers, 1,1,1-trifluoroalkanes, and mixtures thereof (meaning any mixture of compatibilizers disclosed in this section).

[0070] The solubilizer and / or compatibilizer may be selected from the group consisting of hydrocarbon ethers consisting of ethers containing only carbon, hydrogen and oxygen, such as dimethyl ether (DME), and mixtures thereof (meaning any mixture of hydrocarbons disclosed in this section).

[0071] The compatibilizer may be a linear or cyclic aliphatic or aromatic hydrocarbon compatibilizer containing 3 to 15 carbon atoms. The compatibilizer may be at least one hydrocarbon selected from the group consisting of at least propane, including propylene and propane, butane, including n-butane and isobutene, pentane, including n-pentane, isopentane, neopentane and cyclopentane, hexane, octane, nonane, and decane, among others. Commercially available hydrocarbon compatibilizers include, but are not limited to, those sold under the trade name Isopar® H by Exxon Chemical (USA), undecane (C 11 ) and dodecane (C 12 ) and a mixture of high purity C 11 ~C 12 Iso-paraffin), Aromatic 150 (C9~C 11 aromatic), Aromatic200(C9~C 15 Aromatic) and Naptha 140 (C5-C 11 mixtures of paraffinic, naphthenic and aromatic hydrocarbons, and mixtures thereof, meaning mixtures of any of the hydrocarbons disclosed in this section.

[0072] The compatibilizer may alternatively be at least one polymeric compatibilizer. The polymeric compatibilizer may be a random copolymer of a fluorinated acrylate and a non-fluorinated acrylate, the polymer having the formula CH2=C(R 1 )CO2R 2 , CH2=C(R 3 )C6H4R 4 , and CH2=C(R 5 )C6H4XR 6 wherein X is oxygen or sulfur, and R 1, R 3 , and R 5 is independently selected from the group consisting of H and C1-C4 alkyl radicals; R 2 , R 4 , and R 6 are independently selected from the group consisting of carbon chain-based radicals containing C and F, which may further contain H, Cl, ether oxygen, or sulfur in the form of thioether, sulfoxide, or sulfone groups and mixtures thereof. Examples of such polymeric compatibilizers include those available commercially under the trade name Zonyl® PHS from EI du Pont de Nemours and Company (Wilmington, DE, 19898, USA). Zonyl® PHS is a 40 weight percent CH2=C(CH3)CO2CH2CH2(CF2CF2) m F (also called Zonyl® fluoromethacrylate or ZFM), where m is 1 to 12, primarily 2 to 8, 60 weight percent lauryl methacrylate (CH2=C(CH3)CO2(CH2) 11 It is a random copolymer made by polymerizing CH3 (also called LMA).

[0073] In some embodiments, the compatibilizer component contains about 0.01 to 30 weight percent (based on the total weight of the compatibilizer) of an additive that reduces the surface energy of metallic copper, aluminum, steel, or other metals and their alloys found in heat exchangers in a manner that reduces the adhesion of the lubricant to the metal. Examples of additives that reduce metal surface energy include those available from DuPont under the trade names Zonyl® FSA, Zonyl® FSP, and Zonyl® FSJ.

[0074] Another optional non-refrigerant component that may be used with the compositions of the present invention may be a metal surface passivator. The metal surface deactivators are selected from the group consisting of areoxalyl bis(benzylidene)hydrazide (CAS Registry Number 6629-10-3), N,N'-bis(3,5-di-tert-butyl-4-hydroxyhydrocinnamoylhydrazine (CAS Registry Number 32687-78-8), 2,2,'-oxamidobis-ethyl-(3,5-di-tert-butyl-4-hydroxyhydrocinnamate (CAS Registry Number 70331-94-1), N,N'-(disalicyclidene)-1,2-diaminopropane (CAS Registry Number 94-91-7), and ethylenediaminetetra-acetic acid (CAS Registry Number 60-00-4) and its salts, and mixtures thereof (meaning any mixture of metal surface deactivators disclosed in this chapter).

[0075] The optional non-refrigerant component used with the compositions of the present invention may alternatively be a stabilizer selected from the group consisting of hindered phenols, thiophosphates, butylated triphenyl phosphorothioates, organophosphates or phosphites, aryl alkyl ethers, terpenes, terpenoids, epoxides, fluorinated epoxides, oxetanes, ascorbic acid, thiols, lactones, thioethers, amines, nitromethane, alkyl silanes, benzophenone derivatives, aryl sulfides, divinyl terephthalic acid, diphenyl terephthalic acid, ionic liquids, and mixtures thereof (meaning any mixture of stabilizers disclosed in this section).

[0076] The stabilizer may be selected from the group consisting of tocopherol; hydroquinone; t-butylhydroquinone; monothiophosphates, and dithiophosphates (available from Ciba Specialty Chemicals, Basel, Switzerland (hereinafter "Ciba") under the trade name Irgalube® 63); dialkylthiophosphates (available from Ciba under the trade names Irgalube® 353 and Irgalube® 350, respectively); butylated triphenyl phosphorothioates (available from Ciba under the trade name Irgalube® 232); amine phosphates (available from Ciba under the trade name Irgalube® 349 (Ciba)). ba); hindered phosphite (commercially available as Irgafos® 168 from Ciba); and tris-(di-tert-butylphenyl) phosphite (commercially available as Irgafos® OPH from Ciba); (Di-n-octyl phosphite); and iso-decyl diphenyl phosphite (commercially available as Irgafos® DDPP from Ciba); trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate. trialkyl phosphates, such as tri(2-ethylhexyl) phosphate; triaryl phosphates, including triphenyl phosphate, tricresyl phosphate, and trixylenyl phosphate, and mixed alkylaryl phosphates, including isopropylphenyl phosphate (IPPP) and bis(t-butylphenyl)phenyl phosphate (TBPP); butylated triaryl phosphates, such as those commercially available under the trade name Syn-O-Ad®, such as Syn-O-Ad® 8784; Phenyl phosphate; tert-butylated triphenyl phosphate, such as that sold under the trade name Durad® 620; isopropylated triphenyl phosphate, such as that sold under the trade names Durad® 220 and Durad® 110; anisole; 1,4-dimethoxybenzene; 1,4-diethoxybenzene; 1,3,5-trimethoxybenzene; myrcene, alloocimene, limonene (especially d-limonene); retinal; pinene; menthol; geraniol;Farnesol; Phytol; Vitamin A; Terpinene; δ-3-carene; Terpinolene; Phellandrene; Fentane; Dipentene; Caratenoids such as lycopene, xanthophylls such as beta-carotene, and zeaxanthin; Retinoids such as hepaxanthin and isotretinoin; Bornane; 1,2-propylene oxide; 1,2-butylene oxide; n-butyl glycidyl ether; Trifluoromethyloxirane; 1,1-bis(trifluoromethyl)oxirane; 3-ethyl-3-hydroxymethyl-oxetane (e.g., OXT-101 (Toagosei Co., Ltd.)); 3-ethyl-3-((phenoxy)methyl)-oxetane (e.g., OXT-211 (Toagosei Co.,Ltd); 3-ethyl-3-((2-ethyl-hexyloxy)methyl)-oxetane (e.g., OXT-212 (Toagosei Co.,Ltd)); ascorbic acid; methanethiol (methyl mercaptan); ethanethiol (ethyl mercaptan); coenzyme A; dimercaptosuccinic acid (DMSA); grapefruit mercaptan ((R)-2-(4-methylcyclohex-3-enyl)propane-2-thiol); cysteine ​​((R)-2-amino-3-sulfanyl-propanoic acid); lipoamide (1,2-dithiolane-3-pentanamide); 5,7-bis(1,1-dimethylethyl)-3-[2,3(or 3,4)-dimethylphenyl]-2(3H)-benzofuranone (commercially available under the trade name Irganox® HP-136 from Ciba); benzyl phenyl sulfide; dif diisopropylamine; dioctadecyl 3,3'-thiodipropionate (available from Ciba under the trade name Irganox® PS802 (Ciba)); didodecyl 3,3'-thiopropionate (available from Ciba under the trade name Irganox® PS800); di-(2,2,6,6-tetramethyl-4-piperidyl)sebacate (available from Ciba under the trade name Tinuvin® 770); poly-(N-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxy-piperidyl succinate (available from Ciba under the trade name Tinuvin® 622LD (Ciba)); methylbistarylamine;Vistaroamine;phenol-α-naphthylamine;bis(dimethylamino)methylsilane (DMAMS);tris(trimethylsilyl)silane (TTMSS);vinyltriethoxysilane;vinyltrimethoxysilane;2,5-difluorobenzophenone;2',5'-dihydroxyacetophenone;2-aminobenzophenone;2-chlorobenzophenone;benzyl phenyl sulfide;diphenyl sulfide;dibenzyl sulfide;ionic liquids;and mixtures and combinations thereof.

[0077] The optional non-refrigerant component used with the composition of the present invention may alternatively be an ionic liquid stabilizer. The ionic liquid stabilizer may be selected from organic salts that are liquid at room temperature (approximately 25° C.), salts containing a cation selected from the group consisting of pyridinium, pyridazinium, pyrimidinium, pyrazinium, imidazolium, pyrazolium, thiazolium, oxazolium, and triazolium, and mixtures thereof; and an anion selected from the group consisting of [BF4]-, [PF6]-, [SbF6]-, [CF3SO3]-, [HCF2CF2SO3]-, [CF3HFCCF2SO3]-, [HCClFCF2SO3]-, [(CF3SO2)2N]-, [(CF3CF2SO2)2N]-, [(CF3SO2)3C]-, [CF3CO2]-, and F-, and mixtures thereof. In some embodiments, the ionic liquid stabilizer is selected from the group consisting of: emim BF4 (1-ethyl-3-methylimidazolium tetrafluoroborate), bmim BF4 (1-butyl-3-methylimidazolium tetraborate); emim PF6 (1-ethyl-3-methylimidazolium hexafluorophosphate); and bmim PF6 (1-butyl-3-methylimidazolium hexafluorophosphate), all of which are available from Fluka (Sigma-Aldrich).

[0078] In some embodiments, the stabilizer may be a hindered phenol, alkylated monophenols including 2,6-di-tert-butyl-4-methylphenol; 2,6-di-tert-butyl-4-ethylphenol; 2,4-dimethyl-6-tert-butylphenol; hydroquinone and alkylated hydroquinones including t-butylhydroquinone, other derivatives of hydroquinone, such as tocopherols, hydroxylated thiodiphenols including 4,4'-thio-bis(2-methyl-6-tert-butylphenol). alkylidene-bisphenols, including 4,4'-methylenebis(2,6-di-tert-butylphenol), such as 4,4'-thiobis(3-methyl-6-tert-butylphenol); 2,2'-thiobis(4-methyl-6-tert-butylphenol); 4,4'-bis(2,6-di-tert-butylphenol); 2,2- or 4,4-biphenoldiol derivatives; 2,2'-methylenebis(4-ethyl-6-tert-butylphenol); 2,2'-methylenebis(4-methyl-6- tert-butylphenol;4,4-butylidenebis(3-methyl-6-tert-butylphenol);4,4-isopropylidenebis(2,6-di-tert-butylphenol);2,2'-methylenebis(4-methyl-6-nonylphenol);2,2'-isobutylidenebis(4,6-dimethylphenol);2,2'-methylenebis(4-methyl-6-cyclohexylphenol, 2,2- or 4,4-biphenyldiol (2,2'-methylenebis(4-ethyl-6-tert-butylphenol) etc.); butylated hydroxytoluene (BHT, or 2,6-di-tert-butyl-4-methylphenol), bisphenols containing heteroatoms, including (2,6-di-tert-α-dimethylamino-p-cresol, 4,4-thiobis(6-tert-butyl-m-cresol); acylaminophenols, etc.; 2,6-di-tert-butyl-4(N,N'-dimethylaminomethylphenol); sulfides such as; bis(3-methyl-4-hydroxy-5-tert-butylbenzyl)sulfide;Any substituted phenolic compound, such as phenol containing one or more substituted or cyclic straight or branched chain aliphatic substituents, such as bis(3,5-di-tert-butyl-4-hydroxybenzyl) sulfide and mixtures thereof (meaning any mixture of phenols disclosed in this section);

[0079] In some embodiments, the stabilizer may be a single stabilizing compound as detailed above, while in other embodiments, the stabilizer may be a mixture of two or more stabilizing compounds, either from the same class of compounds or from different classes of compounds, this classification being detailed above.

[0080] The optional non-refrigerant component used with the compositions of the present invention may alternatively be a tracer. The tracer may be a single compound or two or more tracer compounds of the same class of compounds or different classes of compounds. In some embodiments, the tracer is present in the composition at a total concentration of about 1 parts per million (ppm) by weight to about 5000 ppm based on the weight of the total composition. In other embodiments, the tracer is present at a total concentration of about 10 ppm to about 1000 ppm. In other embodiments, the tracer is present at a total concentration of about 20 ppm to about 500 ppm. In other embodiments, the tracer is present at a total concentration of about 25 ppm to about 500 ppm. In other embodiments, the tracer is present at a total concentration of about 50 ppm to about 500 ppm. Alternatively, the tracer is present at a total concentration of about 100 ppm to about 300 ppm.

[0081] The tracer may be selected from the group consisting of hydrofluorocarbons (HFCs), deuterated hydrofluorocarbons, chlorofluorocarbons (CFCs), hydrofluorochlorocarbons (HCFCs), chlorocarbons, perfluorocarbons, fluoroethers, brominated compounds, iodinated compounds, alcohols, aldehydes and ketones, nitrous oxide, and combinations thereof. Alternatively, the tracer may be selected from the group consisting of trifluoromethane (HFC-23), dichlorodifluoromethane (CFC-12), chlorodifluoromethane (HCFC-22), methyl chloride (R-40), chlorofluoromethane (HCFC-31), fluoroethane (HFC-161), 1,1-difluoroethane (HFC-152a), 1,1,1-trifluoroethane (HFC-143a), chloropentafluoroethane (CFC-115), 1,2-dichloro-1,1,2 ,2-Tetrafluoroethane (CFC-114), 1,1-dichloro-1,2,2,2-tetrafluoroethane (CFC-114a), 2-chloro-1,1,1,2-tetrafluoroethane (HCFC-124), pentafluoroethane (HFC-125), 1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,1,3,3,3-hexafluoropropane (HFC-236fa), 1,1,1,2,3,3,3-Heptafluoropropane (HFC-227ea), 1,1,1,2,2,3,3-Heptafluoropropane (HFC-227ea), 1,1,1,3,3-Pentafluoropropane (HFC-245fa), 1,1,1,2,2-Pentafluoropropane (HFC-245cb), 1,1,1,2,3-Pentafluoropropane (HFC-245eb), 1,1,2,2-Tetrafluoropropane (HFC-254cb), 1,1 ,1,2-Tetrafluoropropane (HFC-254eb), 1,1,1-Trifluoropropane (HFC-263fb), 1,1-Difluoro-2-chloroethylene (HCFC-1122), 2-Chloro-1,1,2-trifluoroethylene (CFC-1113), 1,1,1,3,3-Pentafluorobutane (HFC-365mfc), 1,1,1,2,3,4,4,5,5,5-Decafluoropentane (HFC-43-10mee), 1,1,1,2,2,The tracer may be selected from the group consisting of 3,4,5,5,6,6,7,7,7-tetradecafluoroheptane, hexafluorobutadiene, 3,3,3-trifluoropropyne, iodotrifluoromethane, deuterated hydrocarbons, deuterated hydrofluorocarbons, perfluorocarbons, fluoroethers, brominated compounds, iodized compounds, alcohols, aldehydes, ketones, nitrous oxide (NO), and mixtures thereof. In some embodiments, the tracer is a blend containing two or more hydrofluorocarbons, or one hydrofluorocarbon combined with one or more perfluorocarbons. In other embodiments, the tracer is a blend of at least one CFC and at least one HCFC, HFC, or PFC.

[0082] Tracers may be added to the compositions of the present invention in a predetermined amount to allow for the detection of any dilution, contamination, or other alteration of the composition. Furthermore, tracers may allow for the detection of products that infringe existing patent rights by distinguishing the patentee's product from competing infringing products. Furthermore, in one embodiment, tracer compounds may allow for the detection of the manufacturing process by which the product is produced, thereby allowing for the detection of the infringement of patents against specific manufacturing process chemistries.

[0083] Additives that may be used with the compositions of the present invention may alternatively be perfluoropolyethers, as described in detail in U.S. Patent Application Publication No. 2007 / 0284555, which is incorporated herein by reference.

[0084] It will be appreciated that certain additives referenced above as suitable for the non-refrigerant components have been identified as potential refrigerants. However, in accordance with the present invention, these additives, if used, are not present in amounts that may affect the novel and fundamental properties of the refrigerant mixtures of the present invention. The refrigerant mixtures and compositions of the present invention containing the refrigerant mixtures preferably contain no more than about 0.5 weight percent of refrigerants other than HFC-32, HFO-1234yf, and CO2.

[0085] In one embodiment, the compositions disclosed herein may be prepared by any convenient method for combining the desired amounts of individual components. A preferred method is to measure the desired amounts of components and then mix the components in a suitable container. Agitation may be used if necessary.

[0086] The compositions of the present invention have zero ozone depletion potential and low global warming potential (GWP). Furthermore, the compositions of the present invention will have a global warming potential that is lower than many hydrofluorocarbon refrigerants currently in use, and even lower than many proposed alternatives.

[0087] Equipment and its use The compositions disclosed herein are useful as heat transfer compositions or refrigerants. In particular, compositions comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2 are useful as refrigerants. Also, compositions comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2 are useful as replacements for R-410A in refrigeration, air conditioning, or heat pump systems. In particular, compositions comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2 are useful as replacements for R-410A in air conditioning and heat pump systems and equipment. Alternatively, compositions comprising a refrigerant mixture consisting of HFC-32, HFO-1234yf, and CO2 are useful as replacements for R-410A in air conditioning and heat pump systems and equipment. Furthermore, compositions comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2 are useful as replacements for R-410A in refrigeration systems and equipment. Additionally, compositions comprising a refrigerant mixture of HFC-32, HFO-1234yf, and CO2 are useful as replacements for R-410A in refrigeration systems and equipment, and the use of the compositions of the present invention in refrigeration systems and equipment is applicable for low temperature and medium temperature refrigeration applications.

[0088] Thus, disclosed herein is a process for producing cooling comprising evaporating a composition comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2 in the vicinity of a body to be cooled, and then condensing said composition. Alternatively, the process for producing cooling comprises evaporating a composition comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2 in the vicinity of a body to be cooled, and then condensing said composition. The use of the method may be, in one embodiment, refrigeration, air conditioning, and heat pumps. In another embodiment, the use of the method for cooling may be refrigeration. In another embodiment, the use of the method for cooling may be low temperature refrigeration. In another embodiment, the use of the method for cooling may be medium temperature refrigeration. In another embodiment, the use of the method for cooling may be air conditioning. In another embodiment, the use of the method for cooling may be a heat pump.

[0089] In another embodiment, disclosed herein is a process for producing heat comprising evaporating a composition comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2, and then condensing said composition in the vicinity of a body to be heated. Alternatively, a process for producing heat comprises evaporating a composition comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2, and then condensing said composition in the vicinity of a body to be heated. The use of this method, in one embodiment, is a heat pump.

[0090] Vapor-compression refrigeration, air conditioning, and heat pump systems include an evaporator, a compressor, a condenser, and an expansion device. The refrigeration cycle reuses refrigerant in multiple steps, producing a cooling effect in one step and a heating effect in a different step. The cycle can be simply described as follows: Liquid refrigerant passes through an expansion device and enters an evaporator, where it boils and removes heat from the environment, forming a gas at a lower temperature and producing cooling. Often air or a heat transfer fluid flows over or around the evaporator to transfer the cooling effect created by the evaporation of the refrigerant in the evaporator to the object to be cooled. The low pressure gas enters a compressor, where the gas is compressed and its pressure and temperature are increased. The high pressure (compressed) gaseous refrigerant then enters a condenser, where the refrigerant condenses and releases its heat to the environment. The refrigerant returns to the expansion device, through which the liquid expands from the higher pressure level in the condenser to the lower pressure level in the evaporator, thus repeating the cycle.

[0091] An object to be cooled or heated may be defined as any space, location, thing, or object for which it is desirable to provide cooling or heating. Examples include spaces (open or enclosed) requiring air conditioning, cooling, or heating, such as rooms, apartments, or buildings, such as apartment buildings, college dormitories, houses or other accessory or single-family homes, hospitals, office buildings, supermarkets, classrooms or administrative buildings of a college or university, and passenger compartments of automobiles or trucks.

[0092] By "proximate" it is meant that the evaporator of the system containing the refrigerant composition is located either within or in close proximity to the object to be cooled, such that the air moved through the evaporator moves through or around the object to be cooled. In a process that produces heating, "proximate" means that the condenser of the system containing the refrigerant composition is located either within or in close proximity to the object to be heated, such that the air moved through the evaporator moves through or around the object to be heated.

[0093] A method for replacing R-410A in an air conditioning or heat pump system is provided, the method comprising substituting said R-410A in place of R-410A for said air conditioning or heat pump system with a composition comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2. Alternatively, the method for replacing R-410A in an air conditioning or heat pump system comprises substituting said R-410A in place of R-410A for said air conditioning or heat pump system with a composition comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2.

[0094] In many cases, replacement refrigerants are most useful if they can be used in cooling equipment originally designed for a different refrigerant. In addition, compositions as disclosed herein may be useful as replacements for R-410A in equipment designed for R-410A with minimal or no system modifications. Furthermore, the compositions may be useful in replacing R-410A in equipment specifically modified or manufactured entirely for these new compositions, including HFC-32, HFO-1234yf, and CO2.

[0095] In many applications, some embodiments of the disclosed compositions are useful as refrigerants, providing at least equivalent cooling performance (meaning cooling capacity) as the refrigerants for which replacements are sought.

[0096] In one embodiment, a method is provided for replacing R-410A, comprising charging an air conditioning or heat pump system with a composition comprising a refrigerant mixture consisting of HFC-32, HFO-1234yf, and CO2 as a replacement for R-410A.

[0097] In one embodiment of the method, the cooling capacity provided by the composition comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2 is within about ±10% of the cooling capacity provided by R-410A under the same operating conditions. In another embodiment of the method, the cooling capacity provided by the composition comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2 is within about ±5% of the cooling capacity provided by R-410A under the same operating conditions. In another embodiment of the method, the cooling capacity provided by the composition comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2 is within about ±2% of the cooling capacity provided by R-410A under the same operating conditions.

[0098] Further disclosed herein is an air conditioning or heat pump system including an evaporator, a compressor, a condenser, and an expansion device, characterized in that the system includes a composition including HFC-32, HFO-1234yf, and CO2.

[0099] In another embodiment, disclosed herein is a refrigeration system including an evaporator, a compressor, a condenser, and an expansion device, characterized in that the composition includes HFC-32, HFO-1234yf, and CO. The equipment can be intended for low temperature or medium temperature cooling.

[0100] The compositions of the present invention have been found to have some temperature gradients within the heat exchanger. This allows the system to operate more efficiently when the heat exchanger is operated in a countercurrent mode or cross-current with a countercurrent tendency. Countercurrent tendency means that the closer the heat exchanger is to a countercurrent mode as possible, the more efficient the heat transfer is. Thus, air conditioning heat exchangers, especially evaporators, are designed to provide some aspect of countercurrent tendency. Thus, an air conditioning or heat pump system is provided herein, which includes one or more heat exchangers (either evaporator, condenser, or both) operating in a countercurrent mode or cross-current with a countercurrent tendency.

[0101] Additionally, the compositions of the present invention may be used in systems with heat exchangers operating in cross-flow mode.

[0102] In another embodiment, a refrigeration, air conditioning or heat pump system is provided herein, the system including one or more heat exchangers (either an evaporator, a condenser, or both) operating in a counterflow mode, a crossflow mode, or a crossflow mode exhibiting counterflow characteristics.

[0103] In one embodiment, the cooling, air conditioning, or heat pump system is a stationary cooling, air conditioning, or heat pump system. In another embodiment, the cooling, air conditioning, or heat pump system is a mobile cooling, air conditioning, or heat pump system.

[0104] Additionally, in some embodiments, the disclosed compositions may function as the primary refrigerant in a secondary loop system that provides cooling to a remote location through the use of a secondary heat transfer fluid that may include water, aqueous saline solutions (e.g., calcium chloride), glycol, carbon dioxide, or fluorinated hydrocarbon fluids, where the secondary heat transfer fluid is adjacent to the evaporator and is the body to be cooled as it is cooled prior to being transferred to a second, remote body to be cooled.

[0105] Examples of air conditioning or heat pump systems include, but are not limited to, residential air conditioners, residential heat pumps, chillers including flooded evaporator chillers and direct expansion chillers, mobile air conditioning units, dehumidifiers, and combinations thereof.

[0106] As used herein, a mobile chiller, air conditioning, or heat pump system refers to any cooling, air conditioning, or heat pump equipment that is incorporated into a road, rail, sea, or air transportation unit. A mobile air conditioning or heat pump system may be used in an automobile, truck, train, or other transportation system. A mobile chiller may include a truck, plane, or train transportation chiller. Additionally, equipment meant to provide cooling to any mobile carrier-independent system, known as an "intermodal" system, is included in the present invention. Such intermodal systems include "containers" (sea / land intermodal) and "swap bodies" (road and rail intermodal).

[0107] As used herein, a stationary air conditioning or heat pump system is a system that is fixed in place during operation. Stationary air conditioning or heat pump systems may be associated with or attached to any of a variety of buildings. These stationary applications may be stationary air conditioning and heat pumps, including but not limited to chillers, heat pumps including high temperature residential heat pumps, residential, commercial, or industrial air conditioning systems, and may include window mounted packaged terminals and their exteriors that are connected to buildings such as rooftop systems, with or without ducts.

[0108] Examples of cooling systems in which the compositions of the present disclosure may be useful include commercial, industrial, or residential refrigerators and freezers, ice machines, self-contained coolers and freezers, flooded evaporator chillers, direct expansion chillers, walk-in and reach-in coolers and freezers, and combined systems. In some embodiments, the disclosed compositions may be used in supermarket cooling systems. Additionally, stationary applications may utilize a secondary loop system that uses a primary refrigerant to generate cooling in one location, which is then moved to a remote location via a secondary heat transfer fluid.

[0109] In the refrigeration, air conditioning, and heat pump systems of the present invention, the heat exchangers operate within certain temperature limits. In air conditioning, in one embodiment, the evaporator operates at a midpoint temperature of about 0° C. to about 20° C. In another embodiment, the evaporator operates at a midpoint temperature of about 0° C. to about 15° C. In yet another embodiment, the evaporator operates at a midpoint temperature of about 5° C. to about 10° C.

[0110] For mid-temperature cooling, in one embodiment, the evaporator operates at a midpoint temperature of about -25° C. to about 0° C. In another embodiment, the evaporator operates at a midpoint temperature of about -18° C. to about -1° C.

[0111] For low temperature cooling, in one embodiment, the evaporator operates at a midpoint temperature of about -45°C to about -10°C. In another embodiment, the evaporator operates at a midpoint temperature of about -40°C to about -18°C.

[0112] In one embodiment, the condenser operates at an average temperature between about 15° C. and about 60° C. In another embodiment, the condenser operates at a midpoint temperature between about 20° C. and about 60° C. In another embodiment, the condenser operates at a midpoint temperature between about 20° C. and about 50° C. EXAMPLES

[0113] The concepts disclosed herein are further illustrated in the following examples, which do not limit the scope of the invention as described in the claims.

[0114] (Example) Cooling performance The cooling performance of the compositions of the present invention was measured under typical conditions for air conditioning and heat pump equipment, and is shown in Table 1 in comparison with R-410A. The GWP values ​​are from the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report, Working Group I, 2007 (AR4). The average temperature gradient (average temperature gradient: average of the temperature gradient in the evaporator and the temperature gradient in the condenser), cooling capacity (capacity), and compressor discharge temperature (Compr Disch Temp) are calculated from the measurements of the physical properties of the compositions of the present invention under the following specific conditions: Evaporator temperature 50°F (10°C) Condenser temperature 115°F (46.1°C) Superheat amount 20°F (11.1K) Supercooling amount 15°F (8.3K) Compressor efficiency 70%

[0115] [Table 2]

[0116] All of the compositions of the present invention shown in Table 1 provide volumetric capacities within ±10% of that of R-410A while providing an average temperature gradient of less than 8° C. and having reasonable compressor discharge temperatures compared to R-410A. Many of the compositions in Table 1 provide volumetric capacities within ±5% of that of R-410A. Additionally, several of the compositions in Table 1 provide capacities within ±2% of that of R-410A. All of the compositions also exhibit excellent energy efficiency (as a COP relative to R-410A), with many of the compositions being improved over R-410A.

[0117] Selected Embodiments Embodiment A1: A composition comprising a refrigerant mixture for replacing R-410A consisting essentially of difluoromethane, 2,3,3,3-tetrafluoropropene, and carbon dioxide.

[0118] Embodiment A2: The composition of embodiment A1 comprising a refrigerant mixture for replacing R-410A consisting essentially of about 42 to about 59 weight percent difluoromethane, about 33 to about 53 weight percent 2,3,3,3-tetrafluoropropene, and about 1 to about 9 weight percent carbon dioxide.

[0119] Embodiment A3: The composition of any of embodiments A1 and A2, wherein the refrigerant mixture consists essentially of from about 42 to about 59 weight percent difluoromethane, from about 35 to about 51 weight percent 2,3,3,3-tetrafluoropropene, and from about 2 to about 9 weight percent carbon dioxide.

[0120] Embodiment A4: The composition of any of Embodiments A1-A3, wherein the refrigerant mixture consists essentially of about 42 to 59 weight percent difluoromethane, about 37 to 48 weight percent 2,3,3,3-tetrafluoropropene, and about 3 to 9 weight percent carbon dioxide.

[0121] Embodiment A5: The composition of any of Embodiments A1-A4, wherein the refrigerant mixture consists essentially of about 42 to 47 weight percent difluoromethane, about 40 to 49 weight percent 2,3,3,3-tetrafluoropropene, and about 3 to 9 weight percent carbon dioxide.

[0122] Embodiment A6: The composition of any of Embodiments A1-A5, wherein the refrigerant mixture consists essentially of about 44 to 47 weight percent HFC-32, about 40 to 49 weight percent 2,3,3,3-tetrafluoropropene, and about 5 to 9 weight percent CO2.

[0123] Embodiment A7: The composition of any of Embodiments A1-A6, wherein the refrigerant mixture consists essentially of about 42 to 45 weight percent difluoromethane, about 46 to 49 weight percent 2,3,3,3-tetrafluoropropene, and about 6 to 9 weight percent carbon dioxide.

[0124] Embodiment A8: The composition of any of Embodiments A1-A7, wherein the refrigerant mixture consists essentially of about 42 to 44 weight percent difluoromethane, about 48 to 51 weight percent 2,3,3,3-tetrafluoropropene, and about 7 to 9 weight percent carbon dioxide.

[0125] Embodiment A9: The composition of any of Embodiments A1-A8, wherein the refrigerant mixture consists essentially of about 44 weight percent difluoromethane, about 49 weight percent 2,3,3,3-tetrafluoropropene, and about 7 weight percent carbon dioxide.

[0126] Embodiment A10: The composition of any of Embodiment A1, wherein the refrigerant mixture consists essentially of from about 47 to about 59 weight percent difluoromethane, from about 37 to about 49 weight percent 2,3,3,3-tetrafluoropropene, and from about 3 to about 8 weight percent carbon dioxide.

[0127] Embodiment A11: The composition of any of Embodiments A1 and A10, wherein the refrigerant mixture consists essentially of from about 52 to about 59 weight percent difluoromethane, from about 37 to about 42 weight percent 2,3,3,3-tetrafluoropropene, and from about 3 to about 6 weight percent carbon dioxide.

[0128] Embodiment A12: The composition of any of Embodiments A1, A10, and A11, wherein the refrigerant mixture consists essentially of about 58 weight percent difluoromethane, about 38 weight percent 2,3,3,3-tetrafluoropropene, and about 4 weight percent carbon dioxide.

[0129] Embodiment A13: The composition of any of Embodiments A1 and A10-A12, wherein the refrigerant mixture consists essentially of about 58 weight percent difluoromethane, about 38 weight percent 2,3,3,3-tetrafluoropropene, and about 4 weight percent carbon dioxide.

[0130] Embodiment A14: The composition of any of Embodiments A1-A13, further comprising one or more components selected from the group consisting of lubricants, dyes, solubilizers, compatibilizers, stabilizers, tracers, antiwear agents, extreme pressure additives, corrosion and oxidation inhibitors, metal surface energy reducers, metal surface deactivators, free radical scavengers, foam control agents, viscosity index improvers, pour point depressants, detergents, viscosity modifiers, and mixtures thereof.

[0131] Embodiment A15: The composition of any of Embodiments A1-A13, further comprising a lubricant selected from the group consisting of mineral oil, alkylbenzene, polyol ester, polyalkylene glycol, polyvinyl ether, polycarbonate, perfluoropolyether, synthetic paraffin, synthetic naphthene, polyα-olefin, and combinations thereof.

[0132] Embodiment A16: The composition of embodiment A14, wherein the lubricant is selected from the group consisting of mineral oils, alkylbenzenes, polyol esters, polyalkylene glycols, polyvinyl ethers, polycarbonates, perfluoropolyethers, synthetic paraffins, synthetic naphthenes, polyα-olefins, and combinations thereof.

[0133] Embodiment B1: A process for producing cooling, comprising condensing a composition according to any of embodiments A1-A12 and then evaporating said composition in the vicinity of a body to be cooled.

[0134] Embodiment B2: A process for producing heating, comprising evaporating a composition according to any one of embodiments A1 to A12, and then condensing said composition in the vicinity of an object to be heated.

[0135] Embodiment C1: A method of replacing R-410A in an air conditioning or heat pump system comprising providing a composition according to any of embodiments A1-A12 to the system as a replacement for R-410A in the air conditioning or heat pump system.

[0136] Embodiment C2: A method of replacing R-410A in a refrigeration system comprising providing a composition according to any of embodiments A1-A12 to the system as a replacement for R-410A in the air conditioning or heat pump system.

[0137] Embodiment C3: The method of embodiment C1, wherein the system includes an evaporator, and the evaporator operates at a midpoint temperature of about 0°C to about 20°C.

[0138] Embodiment C4: The method of embodiment C2, wherein the system includes an evaporator, and the evaporator operates at a midpoint temperature of about -45°C to about -10°C.

[0139] Embodiment C5: The method of embodiment C2, wherein the system includes an evaporator, and the evaporator operates at a midpoint temperature of about -25°C to about 0°C.

[0140] Embodiment D1: An air conditioning or heat pump system comprising an evaporator, a compressor, a condenser, and an expansion device, characterized in that it comprises the composition according to any one of embodiments A1 to A12.

[0141] Embodiment D2: An air conditioning or heat pump system as described in embodiment D1, wherein the system includes one or more heat exchangers operating in counterflow mode, crossflow mode, or crossflow mode exhibiting counterflow characteristics.

[0142] Embodiment D3: A cooling system comprising an evaporator, a condenser, a compressor, and an expansion device, characterized in that it comprises the composition according to any one of embodiments A1 to A12.

[0143] Embodiment D4: The cooling system of embodiment D3, wherein the system includes one or more heat exchangers operating in counterflow mode, crossflow mode, or crossflow mode exhibiting counterflow characteristics.

[0144] Embodiment D5: The cooling system of embodiment D3 or D4, wherein the system includes a low-temperature cooling system and the evaporator operates at a midpoint temperature of about -45°C to about -10°C.

[0145] Embodiment D6: The cooling system of embodiment D3 or D4, wherein the system includes a mid-temperature cooling system and the evaporator operates at a midpoint temperature of about -25°C to about -0°C.

[0146] Embodiment D7: The air conditioning or heat pump system of embodiment D1 or D2, wherein the evaporator operates at a midpoint temperature of about 0°C to about 20°C.

[0147] Embodiment E1: The composition of any of embodiments A1-A12, the process of embodiment B1 or B2, the method of embodiment C1-C5, or the system of any of embodiments D1-D7, wherein the refrigerant mixture has a GWP of 400 or less.

[0148] Embodiment E2: The composition of any of embodiments A1-A12, the process of embodiment B1 or B2, the method of embodiment C1-C5, or the system of any of embodiments D1-D7, wherein the refrigerant mixture has a GWP of 300 or less.

Claims

1. 1. A method of replacing R-410A in an air conditioning or heat pump system, comprising providing a composition comprising a refrigerant mixture consisting essentially of 42 to 59 weight percent difluoromethane, 33 to 53 weight percent 2,3,3,3-tetrafluoropropene, and 1 to 9 weight percent carbon dioxide as a replacement for R-410A in said air conditioning or heat pump system.

2. 2. The method of claim 1, wherein the refrigerant mixture consists essentially of 42 to 59 weight percent difluoromethane, 35 to 51 weight percent 2,3,3,3-tetrafluoropropene, and 2 to 9 weight percent carbon dioxide.

3. The method of claim 1, wherein the refrigerant mixture consists essentially of 42 to 59 weight percent difluoromethane, 37 to 48 weight percent 2,3,3,3-tetrafluoropropene, and 3 to 9 weight percent carbon dioxide.

4. The method of claim 1, wherein the refrigerant mixture consists essentially of 42 to 47 weight percent difluoromethane, 40 to 49 weight percent 2,3,3,3-tetrafluoropropene, and 3 to 9 weight percent carbon dioxide.

5. The method of claim 1, wherein the refrigerant mixture consists essentially of 42 to 45 weight percent difluoromethane, 46 to 49 weight percent 2,3,3,3-tetrafluoropropene, and 6 to 9 weight percent carbon dioxide.

6. The method of claim 1, wherein the refrigerant mixture consists essentially of 42 to 44 weight percent difluoromethane, 48 to 51 weight percent 2,3,3,3-tetrafluoropropene, and 7 to 9 weight percent carbon dioxide.

7. The method of claim 1, wherein the refrigerant mixture consists essentially of 43 to 44 weight percent difluoromethane, 48 to 50 weight percent 2,3,3,3-tetrafluoropropene, and 7 to 8 weight percent carbon dioxide.

8. The method of claim 1, wherein the refrigerant mixture consists essentially of 44 weight percent difluoromethane, 49 weight percent 2,3,3,3-tetrafluoropropene, and 7 weight percent carbon dioxide.

9. The method of claim 1, wherein the refrigerant mixture consists essentially of 47 to 59 weight percent difluoromethane, 37 to 49 weight percent 2,3,3,3-tetrafluoropropene, and 3 to 8 weight percent carbon dioxide.

10. The method of claim 1, wherein the refrigerant mixture consists essentially of 52 to 59 weight percent difluoromethane, 37 to 42 weight percent 2,3,3,3-tetrafluoropropene, and 3 to 6 weight percent carbon dioxide.

11. The method of claim 1, wherein the refrigerant mixture consists essentially of 57 to 59 weight percent difluoromethane, 37 to 39 weight percent 2,3,3,3-tetrafluoropropene, and 3 to 5 weight percent carbon dioxide.

12. The method of claim 1, wherein the refrigerant mixture consists essentially of 58 weight percent difluoromethane, 38 weight percent 2,3,3,3-tetrafluoropropene, and 4 weight percent carbon dioxide.

13. 10. The method of claim 1, wherein the composition further comprises one or more components selected from the group consisting of lubricants, dyes, solubilizers, compatibilizers, stabilizers, tracers, antiwear agents, extreme pressure additives, corrosion and oxidation inhibitors, metal surface energy reducers, metal surface deactivators, free radical scavengers, foam control agents, viscosity index improvers, pour point depressants, detergents, viscosity modifiers, and mixtures thereof.

14. 14. The method of claim 13, wherein the lubricant is selected from the group consisting of mineral oils, alkylbenzenes, polyol esters, polyalkylene glycols, polyvinyl ethers, polycarbonates, perfluoropolyethers, synthetic paraffins, synthetic naphthenes, poly alpha-olefins, and combinations thereof.

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