BR112020008575B1 - COMPOSITION, PROCESS FOR PRODUCING COOLING, PROCESS FOR PRODUCING HEATING, R-32 REPLACEMENT METHOD AND SYSTEM - Google Patents

Abstract

According to 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 as refrigerants in processes for producing cooling and heating, in methods for replacing refrigerant R-32, and in refrigeration, air conditioning or heat pump systems. These compositions of the invention match the cooling capacity of R-32 with GWP less than 400 or less than 300.

Description

BACKGROUND 1. FIELD OF REVELATION.

[0001] The present disclosure relates to compositions for use in air conditioning or heat pump systems. Particularly, the compositions of the present invention are useful in methods for producing cooling and heating, and in methods for replacing R-32 and air conditioning and heat pump apparatus.

2. DESCRIPTION OF THE RELATED TECHNIQUE.

[0002] The refrigeration industry has worked over the past few decades to find replacement refrigerants for ozone-depleting chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) as a result of the Montreal Protocol. The solution for most soft drink producers has been to sell hydrofluorocarbon (HFC)-based refrigerants. These HFC refrigerants, including HFC-134a, R-32 and R-410A, among others, have zero ozone depletion potential and are therefore not affected by the current regulatory phase-out resulting from the Montreal Protocol. With the implementation of the Kigali amendment to the Montreal Protocol, replacement refrigerants with even lower GWP are being sought.

BRIEF SUMMARY

[0003] It has been discovered that certain compositions comprising difluoromethane, tetrafluoropropene and carbon dioxide have suitable properties to allow their use as replacements for currently available commercial refrigerants, in particular R-32, with relatively high GWP. Therefore, the present inventors have discovered refrigerant gases that are not ozone depleting, have significantly lower direct global warming potential, match the performance of R-32, and are thus environmentally sustainable alternatives.

[0004] According to the present invention, refrigerant compositions are disclosed. The compositions comprise refrigerant mixtures consisting essentially of difluoromethane, tetrafluoropropene and carbon dioxide.

[0005] Refrigerant mixtures are useful as components in compositions also containing non-refrigerant components (for example, lubricants and/or adhesives), in processes for producing cooling or heating, in methods for replacing R-32 refrigerant, and, in particular, in air conditioning and heat pump appliances.

DETAILED DESCRIPTION

[0006] Before dealing with the details of the modalities described below, some terms are defined or clarified.

DEFINITIONS

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

[0008] A heat source is defined as any space, location, object or body from which heat is desired to be added, transferred, moved or removed. Examples of heat sources are spaces (open or closed) that require refrigeration or cooling, such as display-style refrigerators or freezers in a supermarket, refrigerated shipping containers, building spaces that require air conditioning, industrial water coolers, or the passenger compartment of an automobile that requires air conditioning. In some embodiments, the heat transfer composition may remain in a constant state throughout the transfer process (i.e., not evaporate or condense). In other embodiments, evaporative cooling processes may also use heat transfer compositions.

[0009] A heat sink is defined as any space, location, object or body capable of absorbing heat. A vapor compression refrigeration system is an example of such a heat sink.

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

[0011] A heat transfer system is the system (or apparatus) used to produce a heating or cooling effect in a specific space. A heat transfer system can be a mobile system or a stationary system.

[0012] Examples of heat transfer systems are any type of refrigeration systems and air conditioning systems including, but not limited to, stationary heat transfer systems, air conditioners, freezers, refrigerators, heat pumps , water coolers, flooded evaporator coolers, direct expansion coolers, walk-in coolers, mobile coolers, 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 a refrigerant in an evaporator per pound-mass of refrigerant circulated, or the heat removed by the refrigerant in the evaporator per unit volume of vapor of refrigerant leaving the evaporator (volumetric capacity). Refrigeration capacity is a measure of the ability of a refrigerant or composition to transfer heat to produce cooling. Therefore, the higher the capacity, the greater the cooling that is produced. Cooling rate refers to the heat removed by the refrigerant in the evaporator per unit time.

[0014] Coefficient of performance ("COP") is the amount of heat removed divided by the energy required to operate the cycle. The higher the COP, the greater the energy efficiency. The COP is directly related to the Energy Efficiency Ratio ("EER"), which is the efficiency rating for refrigeration or air conditioning equipment at a specific indoor and outdoor temperature setting.

[0015] The term "subcooling" refers to reducing the temperature of a liquid below the saturation point of that liquid at a given pressure. Saturation point is the temperature at which vapor is completely condensed into liquid, but subcooling continues to cool the liquid to a lower temperature at the given pressure. By cooling a liquid below the saturation temperature (or bubble point temperature), the effective refrigeration capacity can be increased. Subcooling can therefore improve the cooling capacity and energy efficiency of a system. Subcooling amount is the amount of cooling below the saturation temperature (in degrees).

[0016] Superheat is a term that defines the extent to which a vapor composition is heated above its vapor saturation temperature (the temperature at which, when the composition is cooled, the first drop of liquid is formed, also called " Dew point").

[0017] Temperature slip (sometimes simply called "slip") is the absolute value of the difference between the initial temperature and the final temperature of a phase change process by a refrigerant within a component of a refrigerant system, without include any undercooling or superheating. This term can be used to describe the condensation or evaporation of a quasi-azeotrope or non-azeotropic composition. When referring to the temperature slip of a refrigeration, air conditioning or heat pump system, it is common to present the average temperature slip as being the average of the temperature slip in the evaporator and the temperature slip in the condenser.

[0018] Liquid refrigeration effect is the amount of heat that each kilogram of refrigerant absorbs in the evaporator to produce useful cooling.

[0019] Mass flow rate is the amount of refrigerant in kilograms circulating through the refrigeration, heat pump or air conditioning system during a given period of time.

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

[0021] As used herein, compatibilizers are compounds that improve the hydrofluorocarbon solubility of the compositions disclosed in heat transfer system lubricants. In some embodiments, compatibilizers improve 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, the term "oil return" refers to the ability of a heat transfer composition to transport lubricant through a heat transfer system and return it to the compressor. That is, in use, it is not uncommon for some portion of the compressor lubricant to be removed by the compressor heat transfer composition into other portions of the system. In such systems, if the lubricant does not return efficiently to the compressor, the compressor will eventually fail due to lack of lubrication.

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

[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 minimum concentration of the heat transfer composition in air that is capable of propagating a flame through a mixture homogeneous composition and air under the test conditions specified by the American Society of Testing and Materials ("ASTM") standard E-681. The upper flammability limit ("UFL") is the maximum concentration of the heat transfer composition in air that is capable of propagating a flame through a homogeneous mixture of the composition and air under the same heat transfer conditions. test. The determination of the flammability of a refrigerant compound or a refrigerant mixture is also made by testing under the conditions of ASTM-681.

[0025] During a refrigerant leak, the lower boiling components of a mixture may leak preferentially. Therefore, the composition in the system, and therefore the vapor leak, may vary over the time period of the leak. Therefore, a non-flammable mixture can become flammable under leak scenarios. And 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 when 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 specific greenhouse gas compared to the emission of one kilogram of carbon dioxide. GWP can be calculated for different time horizons, showing the effect of atmospheric lifetime for a given gas. GWP for a 100-year time horizon is commonly the reference 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 refers to the amount of ozone depletion caused by a substance. ODP is the ratio of the influence on ozone of a chemical compound compared to the influence on ozone of a similar mass of CFC-11 (fluorotrichloromethane). Therefore, the ODP of CFC-11 is defined as being equal to 1.0. Other CFCs and HCFCs have ODPs that are in the range of 0.01 to 1.0. HFCs and HFOs have zero ODP 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 encompass a non-exclusive inclusion. For example, a composition, process, method, article and/or apparatus comprising a list of elements is not necessarily limited to those elements only, but may include other elements not expressly listed or inherent in such composition, process, method. , article or device.

[0029] The transitional phrase "consisting of" excludes any unspecified element, step or ingredient. If used in the claim, such a phrase closes the claim to the inclusion of materials other than those cited, except impurities commonly associated with them. When the phrase "consists of" appears in a clause in the body of a claim, rather than immediately following the preamble, it limits only the element defined in that clause; other elements are not excluded from the claim as a whole.

[0030] The transitional phrase "consisting essentially of" is used to define a composition, method, article, or apparatus that includes materials, steps, aspects, components, or elements other than those literally disclosed, provided that these materials, steps , additional aspects, components, or elements do not significantly affect the basic and new feature(s) of the claimed invention. The term "consisting essentially of" occupies an intermediate meaning between "comprising" and "consisting of". Typically, the components of refrigerant mixtures, and the refrigerant mixtures themselves, may contain small amounts (e.g., less than about 0.5 percent by total weight) of impurities and/or by-products (e.g., from the manufacture of the refrigerant components or from recycling refrigerant components from other systems) that do not significantly affect the new and basic characteristics of the refrigerant mixture.

[0031] Where applicants have defined an invention or a part thereof with an unlimited term such as "comprising", it should be readily understood that (unless otherwise indicated) the description should be interpreted to also describe such an invention using the terms "consisting essentially of" or "consisting of".

[0032] Also, the use of "a" or "an" is used to describe elements and components described here. This is done merely for convenience and to give a general sense of the scope of the invention. This description should be read as including one or at least one and the singular also includes the plural, unless it is obvious that it is meant otherwise.

[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 this invention belongs. Although methods and materials similar or equivalent to those described herein may be used in practicing or testing embodiments of the disclosed compositions, suitable methods and materials are described below. All publications, patent applications and other references mentioned in this document are incorporated herein in their entirety by reference, unless a specific excerpt of text is cited. In case of conflict, this specification, including definitions, will prevail. Furthermore, the materials, methods, and examples are illustrative only and are not intended to be limiting.

[0034] 2,3,3,3-tetrafluoropropene can also be called HFO-1234yf, HFC-1234yf or R-1234yf. HFO-1234yf can be manufactured 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 manufactured by methods known in the art, such as dechlorofluorination of methylene chloride.

[0036] Carbon dioxide (CO2) is available for sale from many gas supply houses or can be produced by any of numerous well-known methods.

COMPOSITIONS

[0037] The refrigerant industry has strived to develop new refrigerant products that provide acceptable performance and environmental sustainability. New regulations related to global warming may impose an upper limit on the global warming potential (GWP) for new refrigerant compositions. Therefore, the industry needs to find low GWP, low toxicity, low ozone depletion potential (ODP) compositions that also provide good cooling and heating performance. Difluoromethane (HFC-32, or R-32) has been found to have desirable properties for a refrigerant or heat transfer composition, but has a moderately high GWP, 675, and therefore lower GWP substitutions for HFC-32 are also being sought.

[0038] In one embodiment, refrigerant mixtures have a GWP of 400 or less, based on AR4 data. In another embodiment, the refrigerant blends have a GWP of 300 or less, based on AR4 data.

[0039] The present inventors have identified refrigerant mixtures that provide performance properties to serve as replacements for R-32 in air conditioning and heat pump appliances. These compositions comprise refrigerant mixtures consisting essentially of difluoromethane, 2,3,3,3-tetrafluoropropene and carbon dioxide. In one embodiment, compositions comprising refrigerant mixtures consist of difluoromethane, 2,3,3,3-tetrafluoropropene and carbon dioxide.

[0040] Identifying substitute refrigerants with the right balance of properties required by certain applications is not a trivial task. The industry has struggled to find high-capacity refrigerants with reasonable temperature glide. In particular, a refrigerant to replace R-32 has been desired that can match the cooling capacity of R-32 with an acceptable temperature slip and with a GWP of 400 or less, or even 300 or less.

[0041] Disclosed in the present invention are compositions comprising refrigerant mixtures to replace R-32, said refrigerant mixtures consisting essentially of from about 42 to about 59 weight percent difluoromethane (HFC-32), about 28 to about from 53 weight percent 2,3,3,3-tetrafluoropropene (HFO-1234yf) and about 4 to about 17 weight percent carbon dioxide (CO2).

[0042] In another embodiment, said refrigerant mixture consists essentially of from about 42 to about 59 weight percent difluoromethane, about 31 to about 49 weight percent 2,3,3,3- tetrafluoropropene, and about 4 to about 17 weight percent carbon dioxide.

[0043] In another embodiment, said refrigerant mixture consists essentially of from about 42 to about 59 weight percent difluoromethane, about 33 to about 48 weight percent 2,3,3,3- tetrafluoropropene, and about 6 to about 15 weight percent carbon dioxide.

[0044] In another embodiment, said refrigerant mixture consists essentially of about 42 to 59 weight percent difluoromethane, about 33 to 46 weight percent 2,3,3,3-tetrafluoropropene and about 6 to 17 percent by weight carbon dioxide.

[0045] In another embodiment, said refrigerant mixture consists essentially of about 47 to 59 weight percent difluoromethane, about 32 to 47 weight percent 2,3,3,3-tetrafluoropropene and about 8 to 13 weight percent carbon dioxide.

[0046] In another embodiment, said refrigerant mixture consists essentially of about 47 to 59 weight percent difluoromethane, about 28 to 46 weight percent 2,3,3,3-tetrafluoropropene and about 4 to 16 percent by weight carbon dioxide.

[0047] In another embodiment, said refrigerant mixture consists essentially of about 47 to 59 weight percent difluoromethane, about 31 to 44 weight percent 2,3,3,3-tetrafluoropropene and about 6 to 13 weight percent carbon dioxide.

[0048] In another embodiment, said refrigerant mixture consists essentially of about 47 to 59 weight percent difluoromethane, about 32 to 42 weight percent 2,3,3,3-tetrafluoropropene and about 8 to 12 percent by weight carbon dioxide.

[0049] In another embodiment, said refrigerant mixture consists essentially of about 42 to 59 weight percent difluoromethane, about 32 to 45 weight percent 2,3,3,3-tetrafluoropropene and about 6 to 15 percent by weight carbon dioxide.

[0050] In another embodiment, said refrigerant mixture consists essentially of about 44 to 59 weight percent difluoromethane, about 32 to 45 weight percent 2,3,3,3-tetrafluoropropene and about 6 to 15 percent by weight carbon dioxide.

[0051] In another embodiment, said refrigerant mixture consists essentially of about 44 to 47 weight percent difluoromethane, about 45 to 50 weight percent 2,3,3,3-tetrafluoropropene and about 6 to 15 percent by weight carbon dioxide.

[0052] In another embodiment, said refrigerant mixture consists essentially of about 42 to 44 weight percent difluoromethane, about 45 to 50 weight percent 2,3,3,3-tetrafluoropropene and about 6 to 13 weight percent carbon dioxide.

[0053] In another embodiment, said refrigerant mixture consists essentially of about 42 to 44 weight percent difluoromethane, about 48 to 49 weight percent 2,3,3,3-tetrafluoropropene and about 7 to 10 percent by weight carbon dioxide.

[0054] In another embodiment, said refrigerant mixture consists essentially of about 43 to 44 weight percent difluoromethane, about 48 to 49 weight percent 2,3,3,3-tetrafluoropropene and about 6 to 8 percent by weight carbon dioxide.

[0055] In another embodiment, said refrigerant mixture consists essentially of about 44 weight percent difluoromethane, about 49 weight percent 2,3,3,3-tetrafluoropropene and about 7 weight percent of carbon dioxide.

[0056] In another embodiment, said refrigerant mixture consists essentially of about 43 to 45 weight percent difluoromethane, about 42 to 46 weight percent 2,3,3,3-tetrafluoropropene and about 9 to 13 weight percent carbon dioxide.

[0057] In another embodiment, said refrigerant mixture consists essentially of about 43 to 45 weight percent difluoromethane, about 43 to 45 weight percent 2,3,3,3-tetrafluoropropene and about 11 to 13 weight percent carbon dioxide.

[0058] In another embodiment, said refrigerant mixture consists essentially of about 44 weight percent difluoromethane, about 44 weight percent 2,3,3,3-tetrafluoropropene and about 12 weight percent of carbon dioxide.

[0059] In another embodiment, said refrigerant mixture consists essentially of about 44 weight percent difluoromethane, about 43 weight percent 2,3,3,3-tetrafluoropropene and about 13 weight percent of carbon dioxide.

[0060] In another embodiment, said refrigerant mixture consists essentially of about 55 to 59 weight percent difluoromethane, about 33 to 35 weight percent 2,3,3,3-tetrafluoropropene and about 7 to 12 percent by weight carbon dioxide.

[0061] In another embodiment, said refrigerant mixture consists essentially of about 57 to 59 weight percent difluoromethane, about 33 to 34 weight percent 2,3,3,3-tetrafluoropropene and about 7 to 9 percent by weight carbon dioxide.

[0062] In another embodiment, said refrigerant mixture consists essentially of about 58 weight percent difluoromethane, about 34 weight percent 2,3,3,3-tetrafluoropropene and about 8 weight percent of carbon dioxide.

[0063] In another embodiment, said refrigerant mixture consists essentially of about 58 weight percent difluoromethane, about 33 weight percent 2,3,3,3-tetrafluoropropene and about 9 weight percent of carbon dioxide.

[0064] In any of the above modalities, the total refrigerant mixture must add up to 100%.

[0065] In one embodiment, refrigerant mixtures provide substitutes for R-32 with cooling capacity within 10% of the cooling capacity of R-32. In another embodiment, the refrigerant mixtures provide substitutes for R-32 with cooling capacity within 5% of the cooling capacity of R-32. In another embodiment, the refrigerant mixtures provide substitutes for R-32 with cooling capacity within 2% of the cooling capacity of R-32. In another embodiment, the refrigerant mixtures provide substitutes for R-32 with cooling capacity that is equal to or better than the cooling capacity of R-32.

[0066] Of specific interest, as replacements for R-32, are the compositions mentioned in Table A. TABLE A

[0067] In some embodiments, in addition to difluoromethane, 2,3,3,3-tetrafluoropropene, and carbon dioxide, the disclosed compositions may comprise optional non-refrigerant components. Thus, disclosed in the present invention are compositions comprising a refrigerant mixture consisting essentially of difluoromethane, 2,3,3,3-tetrafluoropropene and carbon dioxide, further comprising one or more optional non-refrigerant components selected from the group consisting of lubricants, dyes (including UV dyes), solubilizing agents, compatibilizers, stabilizers, tracers, antiwear agents, extreme pressure agents, corrosion and oxidation inhibitors, metal surface energy reducers, metal surface deactivators, free radical scavengers , foam controlling agents, viscosity index improvers, pour point lowering agents, detergents, viscosity adjusters and mixtures thereof. In some embodiments, optional non-refrigerant components may be called additives. In fact, many of these optional non-refrigerant components fall into one or more of these categories and may have qualities that lend themselves to achieving one or more performance characteristics.

[0068] In some embodiments, one or more non-refrigerant components are present in small amounts in relation to the total composition. In some embodiments, the concentration amount 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 additives are present in the disclosed compositions in an amount between about 0.1 weight percent and about 5 weight percent of the total composition or in an amount between about 0.1 weight percent. by weight and about 3.5 percent by weight. The additive component(s) selected for the disclosed composition is/are selected based on utility and/or individual equipment components or system requirements.

[0069] In one embodiment, the lubricant is selected from the group consisting of mineral oil, alkylbenzene, polyol esters, poly(alkylene glycols), poly(vinyl ethers), polycarbonates, perfluoropolyethers, silicones, silicate esters, phosphate esters, paraffins, naphthenes, poly(alpha-olefins) and combinations thereof.

[0070] The lubricants, as disclosed herein, may be commercially available lubricants. For example, the lubricant may be paraffinic mineral oil, sold by BVA Oils as BVM 100 N, naphthenic mineral oils sold by Crompton Co. under the trademarks Suniso® 1GS, Suniso® 3GS and Suniso® 5GS, naphthenic mineral oil sold by Pennzoil under the trademark Sontex® 372LT, naphthenic mineral oil sold by Calumet Lubricants under the trademark Calumet® RO-30, linear alkylbenzenes sold by Shrieve Chemicals under the trademarks Zerol® 75, Zerol® 150 and Zerol® 500, and branched alkylbenzene sold by Nippon Oil as HAB 22, polyol esters (POEs) sold under the trademark Castrol® 100 by Castrol, United Kingdom, poly(alkylene glycols) (PAGs) as RL-488A together to Dow (Dow Chemical, of Midland, Michigan, USA), and mixtures thereof, meaning mixtures of any of the lubricants disclosed in this paragraph.

[0071] In the compositions of the present invention that include a lubricant, the lubricant is present in an amount of less than 40.0 percent by weight of the total composition. In other embodiments, the amount of lubricant is less than 20 percent by weight of the total composition. In other embodiments, the amount of lubricant is less than 10 percent by weight of the total composition. In other embodiments, the amount of lubricant is between about 0.1 weight percent and 5.0 weight percent of the total composition.

[0072] Notwithstanding the above weight reasons for the compositions disclosed herein, it is understood that in some heat transfer systems, while the composition is being used, it may acquire more lubricant from one or more equipment components of such heat transfer system. heat transfer. For example, in some refrigeration, air conditioning, and heat pump systems, lubricants may be loaded into the compressor and/or compressor lubricant reservoir. Such a lubricant could be in addition to any lubricant additive present in the refrigerant in such a system. In use, the refrigerant composition, when in the compressor, may accumulate a quantity of equipment lubricant to change the refrigerant-lubricant composition from the initial ratio.

[0073] The non-refrigerant component used with the compositions of the present invention may include at least one colorant. The dye may be at least one ultraviolet (UV) dye. The UV dye can be a fluorescent dye. The fluorescent dye may be selected from the group consisting of naphthalimides, perylenes, coumarins, anthracenes, phenanthracenes, xanthenes, thioxanthenes, naphthoxanthenes, fluoresceins and derivatives of said dye, and combinations thereof, meaning mixtures of any of the aforementioned dyes or their disclosed derivatives. in this paragraph.

[0074] In some embodiments, the disclosed compositions contain from about 0.001 weight percent to 1.0 weight percent UV dye. In other embodiments, the UV dye is present in an amount of about 0.005 weight percent to about 0.5 weight percent; and in other embodiments, the UV dye is present in an amount of about 0.01 weight percent to about 0.25 weight percent of the total composition.

[0075] The UV dye is a useful component for detecting composition leaks by allowing the fluorescence of the dye to be observed at or in the vicinity of a leak point in an appliance (e.g., refrigeration unit, air conditioner or heat pump) . UV emission, e.g. dye fluorescence, can be observed under ultraviolet light. Therefore, if a composition containing such a UV dye is leaking from a certain point in an apparatus, fluorescence can be detected at the point of leakage, or in the vicinity of the point of leakage.

[0076] Another non-refrigerant component that can be used with the compositions of the present invention can include at least one solubilizing agent selected to improve the solubility of one or more dyes in the disclosed compositions. In some embodiments, the ratio of the weight of dye to the weight of solubilizing agent is in the range of about 99:1 to about 1:1. Solubilizing agents include at least one compound selected from the group consisting of hydrocarbons, hydrocarbon ethers, poly(oxyalkylene glycol) ethers (e.g., dipropylene glycol dimethyl ether), amides, nitriles, ketones, chlorocarbons (such as methylene chloride, trichlorethylene , chloroform or mixtures thereof), esters, lactones, aromatic ethers, fluoroethers and 1,1,1-trifluoroalkanes, and mixtures thereof, meaning mixtures of any of the solubilizing agents disclosed in this paragraph.

[0077] In some embodiments, the non-refrigerant component comprises at least one compatibilizer to improve the compatibility of one or more lubricants with the disclosed compositions. The compatibilizer may be selected from the group consisting of hydrocarbons, hydrocarbon ethers, poly(oxyalkylene glycol) ethers (e.g. dipropylene glycol dimethyl ether), amides, nitriles, ketones, chlorocarbons (such as methylene chloride, trichloroethylene, chloroform or mixtures thereof). same), esters, lactones, aromatic ethers, fluoroethers and 1,1,1-trifluoroalkanes, and mixtures thereof, meaning mixtures of any of the compatibilizers disclosed in this paragraph.

[0078] The solubilizing agent 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, "DiMethyl Ether") and mixtures thereof, meaning mixtures of any of the hydrocarbon ethers disclosed in this paragraph.

[0079] The compatibilizer can be a linear or cyclic aliphatic hydrocarbon-based compatibilizer, or aromatic, containing from 3 to 15 carbon atoms. The compatibilizer may be at least one hydrocarbon, which may be selected from the group consisting of at least propanes, including propylene and propane, butanes, including n-butane and isobutene, pentane, including n-pentane, isopentane, neopentane and cyclopentane, hexanes, octanes, nonanes and decanes, among others. Commercially available hydrocarbon-based compatibilizers include, but are not limited to, those from Exxon Chemical (USA) sold under the trademarks Isopar® H, a mixture of undecane (C11) and dodecane (C12) (a C11 to high purity C12), Aromatic 150 (a C9 to C11 aromatic hydrocarbon), Aromatic 200 (a C9 to C15 aromatic hydrocarbon) and Naphtha 140 (a mixture of C5 to C11 aromatic hydrocarbons, naphthenes and paraffins) and mixtures thereof, meaning mixtures of any of the hydrocarbons disclosed in this paragraph.

[0080] The compatibilizer may, alternatively, be at least one polymeric compatibilizer. The polymeric compatibilizer may be a random copolymer of fluorinated and non-fluorinated acrylates, wherein the polymer comprises repeating units of at least one monomer represented by the formulas CH2=C(R1)CO2R2, CH2=C(R3)C6H4R4, and CH2= C(R5)C6H4XR6, where X is oxygen or sulfur; R1, R3 and R5 are independently selected from the group consisting of H and C1-C4 alkyl radicals; and R2, R4, and R6 are independently selected from the group consisting of carbon chain-based radicals containing C and F, and may additionally contain H, Cl, ether oxygen, or sulfur in the form of thioether, sulfoxide, or sulfone and mixtures thereof. Examples of such polymeric compatibilizers include those available for sale from E. I. du Pont de Nemours and Company (Wilmington, DE, 19898, USA) under the trademark Zonyl® PHS. Zonyl® PHS is a random copolymer prepared by the polymerization of 40 weight percent CH2=C(CH3)CO2CH2CH2(CF2CF2)mF (also called Zonyl® fluoromethacrylate or ZFM) where m is 1 to 12, predominantly 2 to 8, and 60 weight percent lauryl methacrylate (CH2=C(CH3)CO2(CH2)11CH3, also called LMA).

[0081] In some embodiments, the compatibilizer component contains from about 0.01 to 30 weight percent (based on the total amount of compatibilizer) of an additive that reduces the surface energy of metallic copper, metallic aluminum, steel, or other metals and metal alloys thereof found (found) in heat exchangers in a manner that reduces the adhesion of lubricants to the metal. Examples of metal surface energy reducing additives include those available for sale from DuPont under the trademarks Zonyl® FSA, Zonyl® FSP, and Zonyl® FSJ.

[0082] Another optional non-refrigerant component that can be used with the compositions of the present invention can be a metal surface deactivator. The metal surface deactivator is selected from the group consisting of oxalylbis(benzylidene)-hydrazide (CAS Reg. No. 6629-10-3), N,N'-bis(3,5-di-tert-butyl-4- hydroxyhydrocinnamoyl)-hydrazine (CAS Reg. No. 32687-78-8), 2,2'-oxamidobis-ethyl-(3,5-di-tert-butyl-4-hydroxyhydrocinnamate) (Reg. No. CAS Reg. 70331-94-1), N,N'-(dissalicyclidene)-1,2-diaminopropane (CAS Reg. No. 94-91-7) and ethylenediaminetetraacetic acid (CAS Reg. No. 60 -004) and their salts, and mixtures thereof, meaning mixtures of any of the metal surface deactivators disclosed in this paragraph.

[0083] 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 triphenylphosphorothionates, organophosphates, or phosphites, arylalkyl ethers, terpenes, terpenoids, epoxides, epoxides fluorinated compounds, oxetanes, ascorbic acid, thiols, lactones, thioethers, amines, nitromethane, alkylsilanes, benzophenone derivatives, aryl sulfides, divinyl terephthalic acid, diphenyl terephthalic acid, ionic liquids, and mixtures thereof, meaning mixtures of any of the stabilizers disclosed in this paragraph .

[0084] The stabilizer can be selected from the group consisting of tocopherol; hydroquinone; t-butylhydroquinone; monothiophosphates; and dithiophosphates, commercially available from Ciba Specialty Chemicals, Basel, Switzerland, hereinafter "Ciba", under the trademark Irgalube®63; dialkylthiophosphate esters, commercially available from Ciba under the registered trademarks Irgalube®353 and Irgalube® 350, respectively; butylated triphenylphosphorothionates, available for sale from Ciba under the registered trademark Irgalube® 232; amine phosphates, available for sale from Ciba under the registered trademark Irgalube® 349 (Ciba); hindered phosphites, commercially available from Ciba as Irgafos® 168 and tris-(di-tert-butylphenyl) phosphite, commercially available from Ciba under the trademark Irgafos® OPH; (di-n-octyl phosphite); and isodecyl and diphenyl phosphite, available for sale from Ciba under the registered trademark Irgafos® DDPP; trialkyl phosphates, such as trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate and tri(2-ethylhexyl phosphate); triaryl phosphates, including triphenyl phosphate, triclesyl phosphate and trixylenyl phosphate; mixed alkylaryl phosphates, including isopropylphenyl phosphate (IPPP) and bis(t-butylphenyl)phenyl phosphate (TBPP); butylated triphenyl phosphates, such as those available commercially under the trademark Syn-O-Ad® including Syn-O-Ad® 8784; tert-butylated triphenyl phosphates, such as those available commercially under the trademark Durad®620; isopropylated triphenyl phosphates, such as those available commercially under the trademarks Durad® 220 and Durad®110; anisole; 1,4-dimethoxybenzene; 1,4-diethoxybenzene; 1,3,5-trimethoxybenzene; myrcene, allo-ocimene, limonene (in particular, d-limonene); retinal; pinene; menthol; geraniol; farnesol; phytol; Vitamin A; terpinene; delta-3-carene; terpinolene; phellandrene; fenchene; dipentene; carotenoids, such as lycopene, beta-carotene and xanthophylls, such as zeaxanthin; retinoids, such as hepaxanthin and isotretinoin; bornane; 1,2-propylene oxide; 1,2-butylene oxide; n-butyl and glycidyl ether; trifluoromethyloxirane; 1,1-bis(trifluoromethyl)oxirane; 3-ethyl-3-hydroxymethyl-oxetane, such as OXT-101 (Toagosei Co., Ltd); 3-ethyl-3-((phenoxy)methyl)-oxetane, such as OXT-211 (Toagosei Co., Ltd); 3-ethyl-3-((2-ethylhexyloxy)methyl)-oxetane, such as 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-sulfanylpropanoic acid); lipoamide (1,2-dithiolane-3-pentanamide); 5,7-bis(1,1-dimethylethyl)-3- [2,3(or 3,4)-dimethylphenyl]-2(3H)-benzofuranone, available for sale from Ciba under the registered trademark Irganox® HP- 136; benzylphenyl sulfide; diphenyl sulfide; diisopropylamine; Dioctadecyl 3,3'-thiodipropionate, available for sale from Ciba under the registered trademark Irganox® PS 802 (Ciba); Didodecyl 3,3'-thiopropionate, available for sale from Ciba under the registered trademark Irganox® PS 800; di-(2,2,6,6-tetramethyl-4-piperidyl) sebacate, available for sale from Ciba under the registered trademark Tinuvin® 770; poly-(N-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxy-piperidyl succinate), available for sale from Ciba under the registered trademark Tinuvin® 622LD (Ciba); methyl bistallow amine; bis-tallow-amine; phenol-alpha-naphthylamine; bis(dimethylamino)methylsilane (DMAMS); tris(trimethylsilyl)silane (TTMSS); vinyltriethoxysilane; vinyltrimethoxysilane; 2,5-difluorobenzophenone; 2’,5’- dihydroxyacetophenone; 2-aminobenzophenone; 2-chlorobenzophenone; benzylphenyl sulfide; diphenyl sulfide; dibenzyl sulfide; ionic liquids; and their mixtures and combinations.

[0085] The optional non-refrigerant component used with the compositions of the present invention may alternatively be an ionic liquid stabilizer. The ionic liquid stabilizer may be selected from the group consisting of organic salts that are liquid at room temperature (approximately 25°C), those salts containing cations selected from the group consisting of pyridinium, pyridazinium, pyrimidinium, pyrazinium, imidazolium, pyrazolium, thiazolium, oxazolium and triazolium, and mixtures thereof; and anions 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 liquid stabilizers are 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).

[0086] In some embodiments, the stabilizer may be a hindered phenol, which is any substituted phenol compound, including phenols comprising one or more straight-chain, branched, cyclic or substituted aliphatic substituent groups, such as alkylated monophenols including 2, 6-di-tert-butyl-4-methylphenol; 2,6-di-tert-butyl-4-ethylphenol; 2,4-dimethyl-6-tert-butylphenol; tocopherol; and the like, hydroquinone and alkylated hydroquinones including t-butylhydroquinone, other hydroquinone derivatives; and the like, hydroxylated thiodiphenyl ethers, including 4,4'-thio-bis(2-methyl-6 tert-butyl-phenol); 4,4’-thiobis(3-methyl-6-tert-butylphenol); 2,2'-thiobis(4-methyl-6-tert-butylphenol); and the like, alkylidene bisphenols including: 4,4'-methylenebis(2,6-di-tert-butylphenol); 4,4’-bis(2,6-di-tert-butylphenol); derivatives of 2,2'- or 4,4'-biphenoldiols; 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-biphenyldiols including 2,2'-methylenebis(4-ethyl-6-tert-butylphenol); butylated hydroxytoluene (BHT, or 2,6-di-tert-butyl-4-methylphenol), bisphenols comprising heteroatoms including 2,6-di-tert-alpha-dimethylamino-p-cresol, 4,4-thiobis(6-tert -butyl-m-cresol); and the like; acylaminophenols; 2,6-di-tert-butyl-4-(N,N’-dimethylaminomethylphenol); sulfides including; bis(3-methyl-4-hydroxy-5-tert-butyl-benzyl) sulfide; bis(3,5-di-tert-butyl-4-hydroxybenzyl) sulfide and mixtures thereof, meaning mixtures of any of the phenols disclosed in this paragraph.

[0087] In some embodiments, a stabilizer may be a single stabilizing compound as described in detail above. In other embodiments, a stabilizer may be a mixture of two or more of the stabilizing compounds, either from the same class of compounds or from different classes of compounds, said classes being described in detail above.

[0088] The optional non-refrigerant component that is used with the compositions of the present invention may alternatively be a tracer. The tracer can be two or more marker compounds from the same class of compounds or from different classes of compounds. In some embodiments, the tracer is present in the compositions at a total concentration of about 1 part per million by weight (ppm) to about 5,000 ppm, based on the total weight of the composition. In other embodiments, the tracer is present in a total concentration of about 10 ppm to about 1,000 ppm. In other embodiments, the tracer is present in a total concentration of about 20 ppm to about 500 ppm. In other embodiments, the tracer is present in a total concentration of about 25 ppm to about 500 ppm. In other embodiments, the tracer is present in a total concentration of about 50 ppm to about 500 ppm. Alternatively, the tracer is present in a total concentration of about 100 ppm to about 300 ppm.

[0089] The tracer can 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-chloro ( 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), 1,1,1,2,2,3,4,5,5,6,6,7,7,7-tetradecafluoroheptane, hexafluorobutadiene, 3,3,3-trifluoropropyne, iodotrifluoromethane, deuterated hydrofluorocarbons, deuterated hydrofluorocarbons, perfluorocarbons, fluoroethers, brominated compounds, iodinated compounds, alcohols, aldehydes, ketones, nitrous oxide (N2O) and mixtures thereof. In some embodiments, the tracer is a blend containing two or more hydrofluorocarbons, or a hydrofluorocarbon in combination with one or more perfluorocarbons. In other embodiments, the tracer is a blend of at least one CFC and at least one HCFC.

[0090] The tracer can be added to the compositions of the present invention in predetermined amounts to allow detection of any dilution, contamination or other change in the composition. Additionally, tracers can enable the detection of a product that infringes existing patent rights, by identifying the patent owner's product versus the competing infringing product. Furthermore, in one embodiment, tracer compounds may allow detection of a manufacturing process by which a product is produced, thereby allowing detection of infringement of a patent relating to the chemistry of a specific manufacturing process.

[0091] The additive that can be used with the compositions of the present invention can alternatively be a perfluoropolyether, as described in detail in U.S. Publication No. 2007/0284555, incorporated herein by reference.

[0092] It will be recognized that some of the additives cited above as suitable for the non-refrigerant component have been identified as potential refrigerants. However, in accordance with this invention, when these additives are used, they are not present in an amount that would affect the new and basic characteristics of the refrigerant mixtures of this invention. Preferably, refrigerant mixtures and compositions of this invention containing them contain no more than about 0.5 percent by weight of refrigerants other than HFC-32, HFO-1234yf and CO2.

[0093] In one embodiment, the compositions disclosed herein can be manufactured by any convenient method to combine the desired amounts of the individual components. A preferred method is to weigh the desired quantities of components and then combine the components in a suitable container. Agitation may be used if desired.

[0094] The compositions of the present invention may have zero ozone depletion potential and low global warming potential (GWP). Furthermore, the compositions of the present invention may have global warming potentials that are lower than the global warming potentials of many hydrofluorocarbon-based refrigerants currently in use.

APPARATUS AND METHODS OF USE

[0095] The compositions disclosed herein are useful as heat transfer or refrigerant compositions. In particular, compositions comprising HFC-32, HFO-1234yf and CO2 are useful as refrigerants. Also, compositions comprising HFC-32, HFO-1234yf, and CO2 are useful as substitutes 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-32 in air conditioning and heat pump systems and apparatus. Alternatively, compositions comprising a refrigerant mixture consisting of HFC-32, HFO-1234yf and CO2 are useful as replacements for R-32 in air conditioning and heat pump systems and apparatus.

[0096] Thus, the present invention discloses 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 condense said composition. Alternatively, the process for producing cooling comprises evaporating a composition comprising a refrigerant mixture consisting of HFC-32, HFO-1234yf and CO2 in the vicinity of a body to be cooled and then condensing said composition.

[0097] In another embodiment, there is disclosed in the present invention a process for producing heating 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, the process for producing heating comprises evaporating a composition comprising a refrigerant mixture consisting of HFC-32, HFO-1234yf, and CO2 and then condensing said composition in the vicinity of a body to be heated.

[0098] Vapor compression refrigeration, air conditioning and heat pump systems include an evaporator, a compressor, a condenser and an expansion device. A refrigeration cycle reuses the refrigerant in multiple stages to produce a cooling effect in one stage and a heating effect in a different stage. A cycle can be described in a simplified way, as follows. Liquid refrigerant enters an evaporator through an expansion device, and the liquid refrigerant boils inside the evaporator, by removing heat from the environment, at a low temperature to form a gas and produce cooling. Often, air or a heat transfer fluid may flow over or around the evaporator to transfer the cooling effect caused by the evaporation of refrigerant within the evaporator to a body to be cooled. The low pressure gas enters a compressor where the gas is compressed to raise its pressure and temperature. The higher pressure gaseous refrigerant (compressed) then enters the condenser in which the refrigerant condenses and discharges its heat to the environment. The refrigerant returns to the expansion device through which the liquid expands from the higher pressure level inside the condenser to the lower pressure level inside the evaporator, thus repeating the cycle.

[0099] A body to be cooled or heated can be defined as any space, location, object or body for which it is desirable to provide cooling or heating. Examples include spaces (open or closed) that require air conditioning, cooling, or heating, such as a room, an apartment, or a building, such as an apartment building, university dormitory, terraced house, or other attached home. or single family home, hospitals, commercial buildings, supermarkets, classrooms of institutions of higher education or universities, or administration buildings and passenger compartments of automobiles or trucks.

[0100] By "in the vicinity of", it is meant that the evaporator of the system containing the refrigerant composition may be located either within or adjacent to the body to be cooled, such that air moving over the evaporator moves it would go into or around the body to be cooled. In the process for producing heating, "in the vicinity of" means that the condenser of the system containing the refrigerant composition is located either within or adjacent to the body to be heated, so that air moving over the evaporator will move went into or around the body to be heated.

[0101] A method for replacing R-32 in air conditioning or heat pump systems is provided, comprising replacing said R-32 with a composition comprising an air conditioning or heat pump system, in place of of R-32. Alternatively, the method for replacing R-32 in air conditioning or heat pump systems comprises replacing said R-32 with a composition comprising a refrigerant mixture consisting of HFC-32, HFO-1234yf and CO2 in said refrigeration system. air conditioning or heat pump instead of R-32.

[0102] Often, replacement refrigerants are more useful if capable of being used in the original refrigeration equipment designed for a different refrigerant. Additionally, the compositions as disclosed in the present invention may be useful as replacements for R-32 in equipment designed for R-32 with minimal to no modifications to the system. Furthermore, the compositions may be useful for replacing R-32 in equipment specifically modified or produced entirely for these new compositions comprising HFC-32, HFO-1234yf and CO2.

[0103] In many applications, some embodiments of the disclosed compositions are useful as refrigerants and provide cooling performance (meaning cooling capacity) at least comparable to that of the refrigerant for which a substitute is being sought.

[0104] In one embodiment, a method for replacing R-32 is provided, which comprises charging an air conditioning or heat pump system with a composition comprising HFC-32, HFO-1234yf and CO2 as a replacement for the said R-32.

[0105] In one embodiment of the method, the refrigeration capacity produced by the refrigerant composition comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2 is within about ±10% of that produced by R-32 under the same operating conditions. In another embodiment of the method, the refrigeration capacity produced by the composition comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2 is within about ±5% of that produced by R-32 under the same refrigeration conditions. operation. In another embodiment of the method, the refrigeration capacity produced by the composition comprising a refrigerant mixture consisting essentially of HFC-32, HFO-1234yf, and CO2 is within about ±2% of that produced by R-32 under the same refrigeration conditions. operation.

[0106] Additionally, there is disclosed in the present invention an air conditioning or heat pump system comprising an evaporator, a compressor, a condenser and an expansion device characterized by containing a composition comprising HFC-32, HFO-1234yf and CO2 .

[0107] It has been discovered that the compositions of the present invention will have some temperature slip in the heat exchangers. Therefore, systems will operate more efficiently if heat exchangers are operated in countercurrent mode or transverse current mode with countercurrent bias. The countercurrent tendency means that the closer the heat exchanger can achieve countercurrent mode, the more efficient the heat transfer will be. Thus, heat exchangers for air conditioning, in particular evaporators, are intended to provide some aspect of the countercurrent tendency. Therefore, an air conditioning or heat pump system is provided herein, said system including one or more heat exchangers (either evaporators, condensers or both) operating in countercurrent mode or crosscurrent mode with the countercurrent trend.

[0108] Additionally, the compositions of the present invention can be used in systems with heat exchangers operating in transverse current mode.

[0109] In another embodiment, a refrigeration system is provided herein, said system including one or more heat exchangers (either evaporators, condensers or both) that operate in countercurrent mode or transverse current mode, or in transverse current mode with countercurrent tendency.

[0110] In one embodiment, the refrigeration, air conditioning or heat pump system is a stationary refrigeration, air conditioning or heat pump system. In another embodiment, the refrigeration, air conditioning or heat pump system is a mobile refrigeration, air conditioning or heat pump system.

[0111] Additionally, in some embodiments, the disclosed compositions may function as primary refrigerants in secondary loop systems that provide cooling to remote locations through the use of a secondary heat transfer fluid, which may comprise water, an aqueous salt solution (e.g., calcium chloride), a glycol, carbon dioxide, or a fluorinated hydrocarbon fluid. In this case the secondary heat transfer fluid is the body to be cooled, because it is adjacent to the evaporator and is cooled before moving to a remote secondary body to be cooled.

[0112] Examples of air conditioning or heat pump systems include, but are not limited to, air conditioners, residential heat pumps, refrigerators, including flooded evaporator refrigerators and direct expansion refrigerators, mobile air conditioning units, dehumidifiers , and combinations thereof.

[0113] As used herein, "mobile refrigeration, air conditioning or heat pump systems" refers to any refrigeration apparatus, air conditioner or heat pump incorporated into a transport unit for road, rail, sea or air. Air conditioning systems or mobile heat pumps can be used in automobiles, trucks, railway cars or other transportation systems. Mobile refrigeration may include transport refrigeration in trucks, airplanes or railway cars. Furthermore, apparatus which are intended to provide refrigeration for a system independent of any moving vehicle, known as "intermodal" systems, are included in the present inventions. Such intermodal systems include "containers" (combined sea/land transport) and also "swap bodies" (combined road/rail transport).

[0114] As used herein, stationary air conditioning or heat pump systems are systems that are fixed in place during operation. An air conditioning system or stationary heat pump can be associated within or attached to buildings of any variety. These stationary applications may be stationary heat and air conditioning pumps including, but not limited to, refrigerators, heat pumps, including high temperature and residential heat pumps, residential, commercial or industrial air conditioning systems, and including window systems, ductless, ducted, terminal compacts, chillers, and those exterior but not connected to the building/building/building such as building/building/building exterior top cover systems.

[0115] Examples of refrigeration systems in which the disclosed compositions may be useful are equipment including commercial, industrial or residential refrigerators and freezers, ice makers, single-piece refrigerators and freezers, flooded evaporator refrigerators, direct expansion refrigerators , walk-in and reach-in refrigerators and freezers, and combination systems. In some embodiments, the disclosed compositions can be used in supermarket refrigeration systems. Additionally, stationary applications may utilize a secondary loop system that uses a primary refrigerant to produce cooling at one location that is transferred to a remote location via a secondary heat transfer fluid.

[0116] In the air conditioning and heat pump system of the present invention, the heat exchangers will operate within certain temperature limitations. For air conditioning, in one embodiment, the evaporator will operate at a midpoint temperature of about 0°C to about 20°C. In another embodiment, the evaporator will operate at a midpoint temperature of about 0°C to about 15°C. In yet another embodiment, the evaporator will operate at a midpoint temperature of about 5°C to about 10°C. In one embodiment, the condenser will operate at a midpoint temperature of about 15°C to about 60°C. In another embodiment, the condenser will operate at a midpoint temperature of about 20°C to about 60°C.

EXAMPLES

[0117] The concepts disclosed herein will be further described in the following examples, which do not limit the scope of the invention described in the claims.

EXAMPLE COOLING PERFORMANCE

[0118] Cooling performance under typical conditions for air conditioning and heat pump apparatus for the compositions of the present invention is determined and presented in table 1 in comparison to R-32. GWP values are from the "Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report, Working Group I, 2007 (AR4)". Average temperature slip (Average Temp Slip: the average of the evaporator temperature slip and the condenser temperature slip), cooling capacity (Capacity), and compressor discharge temperatures (Comp Desc Temp) are calculated from measurements of the physical properties for the compositions of the present invention under the following specific conditions: Evaporator temperature 50°F (10°C) Condenser temperature 115°F (46.1°C) Amount of superheat 20°F (11.1 K) Subcooling Amount 15°F (8.3 K) Compressor Efficiency 70% TABLE 1

[0119] All compositions of the present invention provided in Table 1 provide volumetric capacity within ±10% of that for R-32, while providing an average temperature slip of less than 8°C and having reasonable compressor discharge temperatures compared to R-32. Many of the compositions in Table 1 provide a volumetric capacity within ±5% of that for R-32. Additionally, some of the compositions in Table 1 provide volumetric capacity within ±2% of that for R-32. And all compositions show reasonable energy efficiency (as COP relative to R-32).

SELECTED MODALITIES

[0120] Modality A1: A composition comprising a refrigerant mixture to replace R-32, said refrigerant mixture consisting essentially of difluoromethane, 2,3,3,3-tetrafluoropropene and carbon dioxide.

[0121] Modality A2: The composition of modality A1 wherein said refrigerant mixture consisting essentially of from about 42 to about 59 weight percent difluoromethane, about 28 to about 53 weight percent of 2.3 ,3,3-tetrafluoropropene and about 4 to about 17 weight percent carbon dioxide.

[0122] Modality A3: The composition of any of modalities A1 and A2 wherein said refrigerant mixture consists essentially of from about 42 to about 59 weight percent difluoromethane, about 31 to about 49 weight percent of 2 ,3,3,3-tetrafluoropropene and about 4 to about 17 weight percent carbon dioxide.

[0123] Modality A4: The composition of any of modalities A1 to A3 wherein said refrigerant mixture consists essentially of from about 42 to about 59 weight percent difluoromethane, about 33 to about 48 weight percent of 2,3,3,3-tetrafluoropropene and about 6 to about 15 weight percent carbon dioxide.

[0124] Modality A5: The composition of any of modalities A1 to A4 wherein said refrigerant mixture consists essentially of about 42 to 59 weight percent difluoromethane, about 33 to 46 weight percent 2.3, 3,3-tetrafluoropropene and about 6 to 17 weight percent carbon dioxide.

[0125] Modality A6: The composition of any of modalities A1 to A5 wherein said refrigerant mixture consists essentially of about 47 to 59 weight percent difluoromethane, about 32 to 47 weight percent 2.3, 3,3-tetrafluoropropene and about 8 to 13 weight percent carbon dioxide.

[0126] Modality A7: The composition of any of modalities A1 to A6 wherein said refrigerant mixture consists essentially of about 47 to 59 weight percent difluoromethane, about 28 to 46 weight percent 2.3, 3,3-tetrafluoropropene and about 4 to 16 weight percent carbon dioxide.

[0127] Modality A8: The composition of any of modalities A1 to A7 wherein said refrigerant mixture consists essentially of about 47 to 59 weight percent difluoromethane, about 31 to 44 weight percent 2.3, 3,3-tetrafluoropropene and about 6 to 13 weight percent carbon dioxide.

[0128] Modality A9: The composition of any of modalities A1 to A8 wherein said refrigerant mixture consists essentially of about 47 to 59 weight percent difluoromethane, about 32 to 42 weight percent 2.3, 3,3-tetrafluoropropene and about 8 to 12 weight percent carbon dioxide.

[0129] Modality A10: The composition of any of modalities A1 to A7 wherein said refrigerant mixture consists essentially of about 42 to 59 weight percent difluoromethane, about 32 to 45 weight percent 2.3, 3,3-tetrafluoropropene and about 6 to 15 weight percent carbon dioxide.

[0130] Modality A11: The composition of any of modalities A1 to A2 wherein said refrigerant mixture consists essentially of about 44 to 47 weight percent difluoromethane, about 45 to 50 weight percent 2.3, 3,3-tetrafluoropropene and about 6 to 15 weight percent carbon dioxide.

[0131] Modality A12: The composition of any of modalities A1 to A2 wherein said refrigerant mixture consists essentially of about 42 to 44 weight percent difluoromethane, about 45 to 50 weight percent 2.3, 3,3-tetrafluoropropene and about 6 to 13 weight percent carbon dioxide.

[0132] Modality A13: The composition of any of modalities A1 to A2, A11 and A12 wherein said refrigerant mixture consists essentially of about 42 to 44 weight percent difluoromethane, about 45 to 50 weight percent of 2,3,3,3-tetrafluoropropene and about 6 to 13 weight percent carbon dioxide.

[0133] Modality A14: The composition of any of modalities A1 to A3 wherein said refrigerant mixture consists essentially of about 42 to 44 weight percent difluoromethane, about 48 to 49 weight percent 2.3, 3,3-tetrafluoropropene and about 7 to 10 weight percent carbon dioxide.

[0134] Modality A15: The composition of any of modalities A1 to A3 wherein said refrigerant mixture consists essentially of about 43 to 44 weight percent difluoromethane, about 48 to 49 weight percent 2.3, 3,3-tetrafluoropropene and about 6 to 8 weight percent carbon dioxide.

[0135] Modality A16: The composition of any of modalities A1 to A3 and A11 to A15 wherein said 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.

[0136] Modality A17: The composition of any of modalities A1 to A7 wherein said refrigerant mixture consists essentially of about 43 to 45 weight percent difluoromethane, about 42 to 46 weight percent 2.3, 3,3-tetrafluoropropene and about 9 to 13 weight percent carbon dioxide.

[0137] Modality A18: The composition of any of modalities A1 to A7 and A17 wherein said refrigerant mixture consists essentially of about 43 to 45 weight percent difluoromethane, about 43 to 45 weight percent of 2, 3,3,3-tetrafluoropropene and about 11 to 13 weight percent carbon dioxide.

[0138] Modality A19: The composition of any of modalities A1 to A7 and A17 to A18 wherein said refrigerant mixture consists essentially of about 44 weight percent difluoromethane, about 44 weight percent 2.3, 3,3-tetrafluoropropene and about 12 weight percent carbon dioxide.

[0139] Modality A20: The composition of any of modalities A1 to A7 and A17 to A18 wherein said refrigerant mixture consists essentially of about 44 weight percent difluoromethane, about 43 weight percent 2.3, 3,3-tetrafluoropropene and about 13 weight percent carbon dioxide.

[0140] Modality A21: The composition of any of modalities A1 to A10 wherein said refrigerant mixture consists essentially of about 55 to 59 weight percent difluoromethane, about 33 to 35 weight percent 2.3, 3,3-tetrafluoropropene and about 7 to 12 weight percent carbon dioxide.

[0141] Modality A22: The composition of any of modalities A1 to A10 and A21 wherein said refrigerant mixture consists essentially of about 57 to 59 weight percent difluoromethane, about 33 to 34 weight percent of 2, 3,3,3-tetrafluoropropene and about 7 to 9 weight percent carbon dioxide.

[0142] Modality A23: The composition of any of modalities A1 to A10 and A21 to A22 wherein said refrigerant mixture consists essentially of about 58 weight percent difluoromethane, about 34 weight percent 2.3, 3,3-tetrafluoropropene and about 8 weight percent carbon dioxide.

[0143] Modality A24: The composition of any of modalities A1 to A10 and A21 to A23 wherein said refrigerant mixture consists essentially of about 58 weight percent difluoromethane, about 33 weight percent 2.3, 3,3-tetrafluoropropene and about 9 weight percent carbon dioxide.

[0144] Modality A25: The composition of any of modalities A1 to A24 that additionally comprises one or more components selected from the group consisting of lubricants, dyes, solubilizing agents, compatibilizers, stabilizers, tracers, antiwear agents, extreme pressure, corrosion and oxidation inhibitors, metal surface energy reducers, metal surface deactivators, free radical scavengers, foam controlling agents, viscosity index improvers, pour point lowering agents, detergents, viscosity adjusters and mixtures thereof.

[0145] Modality A26: The composition of any of modalities A1 to A25 in which said lubricant is selected from the group consisting of mineral oil, alkylbenzene, polyol esters, poly(alkylene glycols), poly(vinyl ethers), polycarbonates, perfluoropolyethers , synthetic paraffins, synthetic naphthenes, poly(alpha-olefins), and combinations thereof.

[0146] Modality A27: The composition of any of modalities A1 to A24 that additionally comprises a lubricant selected from the group consisting of mineral oil, alkylbenzene, polyol esters, poly(alkylene glycols), poly(vinyl ethers), polycarbonates , perfluoropolyethers, synthetic paraffins, synthetic naphthenes, poly(alpha-olefins) and combinations thereof.

[0147] Modality B1: A process for producing cooling comprising condensing the composition of any of modalities A1 to A25 and then evaporating said composition in the vicinity of a body to be cooled.

[0148] Modality B2: A process for producing heating comprising evaporating the composition of any of modalities A1 to A12 and then condensing said composition in the vicinity of a body to be heated.

[0149] Mode B3: The process of any of modes B1 or B2 in which said evaporation is completed in an evaporator and said evaporator operates with temperatures at the midpoint between about 0°C and about 20°C.

[0150] Modality C1: A method for replacing R-32 in air conditioning or heat pump systems, which comprises providing the system with the composition of any of modalities A1 to A25, as a replacement for said R-32 in the said air conditioning or heat pump system.

[0151] Mode C2: The method of mode C1 in which said air conditioning and heat pump system comprises at least one evaporator and said evaporator operates with temperatures at the midpoint between about 0°C and about of 20°C.

[0152] Modality D1: An air conditioning or heat pump system comprising an evaporator, a compressor, a condenser and an expansion device, characterized by containing the composition of any of modalities A1 to A25.

[0153] Mode D2: The air conditioning or heat pump system of mode D1, said system including one or more heat exchangers that operate in countercurrent mode, transverse current mode, or in transverse current with the countercurrent tendency.

[0154] Mode D3: The air conditioning or heat pump system of mode D1 or D2, in which said evaporator operates with temperatures at the midpoint between about 0°C and about 20°C.

[0155] Modality E1: The compositions of any of modalities A1 to A25 in which the processes of modalities B1 to B3, the methods of modalities C1 or C2, or the systems of any of modalities D1 to D7, in which the refrigerant mixture has a GWP of 400 or less.

[0156] Modality E2: The compositions of any of modalities A1 to A25 in which the processes of modalities B1 to B3, the methods of modalities C1 or C2, or the systems of any of modalities D1 to D3 in which the refrigerant mixture has a GWP of 300 or less.

Claims (15)

1. COMPOSITION, characterized in that it comprises a refrigerant mixture to replace R-32, said refrigerant mixture consisting of 42 to 59 percent by weight of difluoromethane, 28 to 53 percent by weight of 2,3,3,3- tetrafluoropropene and 4 to 17 weight percent carbon dioxide. 2. COMPOSITION according to claim 1, characterized in that said refrigerant mixture consists of 42 to 59 percent by weight of difluoromethane, 33 to 48 percent by weight of 2,3,3,3-tetrafluoropropene and 6 to 15 percent by weight of percent by weight of carbon dioxide. 3. COMPOSITION according to claim 1, characterized in that said refrigerant mixture consists of 47 to 59 percent by weight of difluoromethane, 32 to 47 percent by weight of 2,3,3,3-tetrafluoropropene and 8 to 13 percent by weight of percent by weight of carbon dioxide. 4. COMPOSITION according to claim 1, characterized in that said refrigerant mixture consists of 47 to 59 percent by weight of difluoromethane, 28 to 46 percent by weight of 2,3,3,3-tetrafluoropropene and 4 to 16 percent by weight of percent by weight of carbon dioxide. 5. COMPOSITION, according to claim 1, characterized in that said refrigerant mixture consists of 47 to 59 percent by weight of difluoromethane, 31 to 44 percent by weight of 2,3,3,3-tetrafluoropropene and 6 to 13 percent by weight of percent by weight of carbon dioxide. 6. COMPOSITION according to claim 1, characterized in that said refrigerant mixture consists of 42 to 44 percent by weight of difluoromethane, 48 to 49 percent by weight of 2,3,3,3-tetrafluoropropene and 7 to 10 percent by weight of percent by weight of carbon dioxide. 7. COMPOSITION according to claim 1, characterized in that said refrigerant mixture consists of 43 to 44 percent by weight of difluoromethane, 48 to 49 percent by weight of 2,3,3,3-tetrafluoropropene and 6 to 8 percent by weight of percent by weight of carbon dioxide. 8. COMPOSITION, according to claim 1, characterized in that said refrigerant mixture consists of 55 to 59 percent by weight of difluoromethane, 33 to 35 percent by weight of 2,3,3,3-tetrafluoropropene and 7 to 12 percent by weight of percent by weight of carbon dioxide. 9. COMPOSITION according to claim 1, characterized in that said refrigerant mixture consists of 57 to 59 percent by weight of difluoromethane, 33 to 34 percent by weight of 2,3,3,3-tetrafluoropropene and 7 to 9 percent by weight of percent by weight of carbon dioxide. 10. COMPOSITION, according to claim 1, characterized by additionally comprising one or more components selected from the group consisting of lubricants, dyes, solubilizing agents, compatibilizers, stabilizers, tracers, antiwear agents, extreme pressure agents, inhibitors corrosion and oxidation agents, metal surface energy reducers, metal surface deactivators, free radical scavengers, foam controlling agents, viscosity index improvers, pour point lowering agents, detergents, viscosity adjusters and mixtures thereof . 11. COMPOSITION, according to claim 10, characterized in that said lubricant is selected from the group consisting of mineral oil, alkylbenzene, polyol esters, poly(alkylene glycols), poly(vinyl ethers), polycarbonates, perfluoropolyethers, synthetic paraffins, synthetic naphthenes, poly(alpha-olefins), and combinations thereof. 12. PROCESS FOR PRODUCING COOLING, characterized in that it comprises condensing the composition, as defined in claim 1, and then evaporating said composition in the vicinity of a body to be cooled. 13. PROCESS FOR PRODUCING HEATING, characterized in that it comprises evaporating the composition, as defined in claim 1, and then condensing said composition in the vicinity of a body to be heated. 14. METHOD OF REPLACING R-32 in refrigeration, air conditioning or heat pump systems, characterized in that it comprises providing the composition, as defined in claim 1, as a replacement for said R-32. 15. Air conditioning or heat pump SYSTEM, containing a composition, as defined in claim 1, characterized by comprising an evaporator, a compressor, a condenser and an expansion device.