HEAT TRANSFER COMPOSITIONS

Abstract

A composition comprising: (i) 1,1-difluoroethene (vinylidene fluoride, R-1132a); (ii) carbon dioxide (CO2, R-744); (iii) pentafluoroethane (R-125); and (iv) one or more of trifluoromethane (R-23) and hexafluoroethane (R-116).

Description

HEAT TRANSFER COMPOSITIONS The invention relates to compositions, preferably heat transfer compositions, and in particular to ultra-low temperature heat transfer compositions that may be suitable as replacements for existing refrigerants such as R-23, R-13B1, R-508A or R-508B. The inclusion or discussion of a previously published document or any background information in the description should not necessarily be taken as an acknowledgment that a document or background information is part of the state of the art or is common knowledge. Mechanical refrigeration systems and related heat transfer devices, such as heat pumps and air conditioning systems, are well known. In such systems, a refrigerant liquid evaporates at low pressure and absorbs heat from the surrounding area. The resulting vapor is compressed and passes to a condenser where it condenses and releases heat to a second area. The condensate returns to the evaporator through an expansion valve, thus completing the cycle. The mechanical energy required to compress the vapor and pump the liquid is provided, for example, by an electric motor or an internal combustion engine. Forced air freezer equipment is used for the rapid freezing of food or pharmaceutical products by contact of the product to be frozen inside a closed compartment with low temperature air recirculation. Conventional forced-air freezing of food uses a single-stage refrigeration system to generate rapid cooling to temperatures between approximately -18 and approximately -30 °C. A typical refrigerant used for this would be R404A (by weight, 44% pentafluoroethane (R-125), 52% 1,1,1-trifluoroethane (R-143a), and 4% 1,1,1,2-tetrafluoroethane (R-134a)). Using lower cooling temperatures has been found to enable the long-distance maritime transport of high-value seafood (e.g., sea urchin, swordfish, tuna). Several shipping companies offer refrigerated shipping container systems ('refrigerated container') capable of maintaining temperatures of approximately -60°C. In these cascade systems, a low-temperature refrigeration circuit using trifluoromethane (R-23) cools the container air to -60°C and then dissipates its heat to a second, higher-temperature refrigeration circuit (using R-134a or R-404A). The high-temperature stage then dissipates the heat to the ambient air. These systems work well, but the GWP of R-23 is very high at 14,800. Therefore, a low-flammability or non-flammable refrigerant with a lower GWP capable of replacing R-23 in this application would be desirable. IVIA / a / ZUZÓ / UI U4 / U The pharmaceutical industry also uses forced-air freezing at low temperatures to freeze and preserve active ingredients and other biologically derived materials, as discussed in the reference monograph “Freeze-Drying / Lyophilization of Pharmaceutical and Biological Products, Third Edition,” edited by Louis Rey and published by CRC Press, April 19, 2016, incorporated herein by reference. Specific examples include, but are not limited to, insulin, vaccines, and tissue samples. Traditional refrigerants used in these systems include bromotrifluoromethane (R-13B1), R-23, R-508A (39% R-23, 61% R-116), and R-508B (46% R-23, 56% R-116), where operating temperatures range from approximately -60°C to approximately -90°C. There are several refrigerant and application characteristics that must be considered when developing viable alternatives to R-23 (and other low-temperature refrigerants used in cascade systems), including: • Low flammability • Suitable operating temperature • Similar operating pressure to R-23 • Performance as a refrigerant (e.g., cooling capacity and energy efficiency) • Minimum refrigerant temperature glide • Low global warming potential (GWP) Therefore, designing a suitable refrigerant involves making multiple informed selections of composition and component to arrive at a feasible alternative. One way to assess non-flammability is to apply the flammability analysis methodology stipulated by ASHRAE Standard 34:2016, which prescribes a range of leak scenarios to be applied to refrigerant mixtures to identify potentially flammable compositions in the worst-case scenario. If the fluid is to be used as a retrofit or conversion fluid in existing equipment, or as an addition to new equipment (for example, using an essentially unchanged R-23 system design), then non-flammability is highly desirable, as the existing design will be based on the use of non-flammable fluids. In particular, for larger systems and marine (refrigerated container) applications, non-flammability under all circumstances (including leaks) is strongly preferred. It is also advantageous to have an acceptably low toxicity as a characteristic of the fluid. Volumetric capacity (a measure of the cooling power achievable by a given compressor size) and energy efficiency are important considerations for any system with heat transfer properties. This is especially true IVIA / a / ¿U¿ó / UI U4 / U in cascade operation since any inefficiency in the low temperature stage also increases the compressor's energy consumption in the upper cascade stage. R-170 (ethane) has a very low GWP, acceptable cooling performance, and low toxicity, but its high flammability limits its application. For example, safety regulations may restrict the maximum amount of refrigerant charged in household appliances. R-744 (carbon dioxide) is non-flammable, but it cannot be used alone in the lower stage of low-temperature cascade systems because the operating temperatures are below the triple point of R-744, which is -56.7 °C. This means that solid carbon dioxide (dry ice) could form in the low-pressure sections of the system, leading to blockages, poor control, and inefficient operation. R-1132a (1,1-difluoroethene, also known as vinylidene fluoride) also has a low GWP and acceptable toxicity. The flammability of R-1132a is reduced compared to ethane, but it is still classified as ASHRAE Class 2 (moderately flammable). The thermodynamic energy efficiency of pure R-1132a is close to that of R-508 and better than that of R-23, but its cooling capacity is lower compared to both R-508 and R-23. Therefore, there is a need to provide alternative refrigerants that have improved properties, such as a low GWP, while maintaining acceptable cooling performance, flammability characteristics, and toxicology. There is also a need to provide alternative refrigerants that can be used in existing devices, such as refrigeration units, with little or no modification. The present invention addresses the above and other deficiencies by providing a composition comprising: 1,1-difluoroethene (vinylidene fluoride, R-1132a); carbon dioxide (CO2, R-744); pentafluoroethane (R-125); and one or more of trifluoromethane (R-23) and hexafluoroethane (R-116). The invention also provides for the use of the compositions of the invention as refrigerants, preferably low-temperature refrigerants suitable for use in forced-air freezing equipment. The temperatures achieved using the compositions of the invention as refrigerants can be -60°C or lower, such as -70°C or lower, preferably -80°C or lower, or even -90°C or lower. Surprisingly, the compositions of the invention have been found to exhibit a combination of suitable flammability properties, an operating pressure similar to R-23, cooling performance comparable to or better than R-23, desirable temperature glide, and low GWP. The compositions of the invention may comprise from approximately 1 to approximately 90% by weight of R-1132a, such as from approximately 1 to IVIA / a / ZUZÓ / UI U4 / U approximately 80% by weight, from approximately 1 to approximately 70% by weight, or from approximately 1 to approximately 60% by weight. Preferably, the compositions comprise from approximately 1 to approximately 50% by weight of R-1132a, such as from approximately 5 to approximately 45% by weight, from approximately 10 to approximately 45% by weight, or from approximately 15 to approximately 40% by weight. Advantageously, the compositions may comprise from approximately 20 to approximately 40% by weight of R-1132a, preferably from approximately 25 to approximately 35% by weight of R-1132a. The compositions of the invention may comprise from approximately 1 to approximately 90% by weight of carbon dioxide, such as from approximately 1 to approximately 80% by weight, from approximately 5 to approximately 70% by weight, or from approximately 10 to approximately 60% by weight. Preferably, the compositions comprise from approximately 25 to approximately 60% by weight of carbon dioxide, such as from approximately 30 to approximately 55% by weight, or even more preferably, from approximately 35 to approximately 50% by weight. The compositions of the invention are surprisingly capable of operating below -56.7 °C (the triple point of carbon dioxide) without the formation of dry ice in the system. The compositions of the invention may comprise from approximately 1 to approximately 90% by weight of R-125, such as from approximately 1 to approximately 80% by weight, from approximately 1 to approximately 70% by weight, or from approximately 1 to approximately 60% by weight. Preferably, the compositions comprise from approximately 1 to approximately 50% by weight, such as from approximately 5 to approximately 45% by weight, from approximately 5 to approximately 30% by weight, or even from approximately 10 to approximately 25% by weight. The compositions of the invention may comprise from approximately 1 to approximately 90% by weight of the fourth component, such as from approximately 1 to approximately 80% by weight, from approximately 1 to approximately 70% by weight, or from approximately 1 to approximately 60% by weight. Preferably, the compositions of the invention may comprise from approximately 1 to approximately 50% by weight of the fourth component. In one embodiment, the fourth component comprises or is R-23. Therefore, a preferred composition of the invention comprises R-1132a, CO2, R-125, and R-23. In a preferred embodiment, a composition comprising approximately 20 to approximately 40 wt% of R-1132a, approximately 30 to approximately 60 wt% of carbon dioxide, and approximately 1 to IVIA / a / ¿U¿ó / UI U4 / U approximately 20% by weight of R-23 and from approximately 1 to approximately 35% by weight of R-125. Advantageously, a composition is provided comprising approximately 25 to approximately 35% by weight of R-1132a, approximately 35 to approximately 50% by weight of carbon dioxide, approximately 5 to approximately 15% by weight of R-23, and approximately 5 to approximately 30% by weight of R-125. In a preferred embodiment, a composition comprising approximately 25 to approximately 30 wt% of R-1132a, approximately 35 to approximately 50 wt% of carbon dioxide, approximately 10 to approximately 25 wt% of R-125, and approximately 5 to approximately 20 wt% of R-23 is provided. In an alternative embodiment, the fourth component comprises or is R-116. Therefore, a preferred composition of the invention comprises R-1132a, CO2, R-125, and R-116. In a preferred embodiment, a composition comprising approximately 30 to approximately 60% by weight of carbon dioxide, approximately 10 to approximately 40% by weight of R-1132a, approximately 5 to approximately 30% by weight of R-125, and approximately 1 to approximately 20% by weight of R-116 is provided. A preferred composition of the invention comprises approximately 35 to approximately 55% by weight of carbon dioxide, approximately 15 to approximately 35% by weight of R-1132a, approximately 10 to approximately 30% by weight of R-125, and approximately 1 to approximately 15% by weight of R-116. Advantageously, a composition is provided comprising approximately 25 to approximately 35% by weight of R-1132a (e.g., approximately 30%), approximately 40 to approximately 50% by weight of carbon dioxide (e.g., approximately 45%), approximately 15 to approximately 25% by weight of R-125 (e.g., approximately 20%), and approximately 1 to approximately 15% by weight of R-116 (e.g., approximately 5%). Preferably, R-1132a is present in an amount of less than 50 mol%. The ASHRAE fractionation analysis mentioned above requires an evaluation of the liquid and vapor compositions during vapor leakage from a cylinder and must be performed for two refrigerant charge levels (15% and 90% maximum fill) and over a temperature range of -40°C to +60°C. A composition comprising less than 50 mol% of R-1132a, preferably less than 30 mol%, will result in a weakly flammable or, preferably, non-flammable composition under fractionation analysis. IVIA / a / ¿U¿ó / UI U4 / U The ASHRAE fractionation analysis is conservative in nature. The mixtures of the invention, such as R-23, will typically have critical temperatures close to ambient temperature. This means that if the system is not in operation and warms to ambient temperature, the mixture may be above its critical temperature. In this case, it will exist as a homogeneous supercritical fluid. Therefore, leakage would be from the bulk composition, not from a fractionated vapor. Thus, if the total volume of the fluid is nonflammable, the composition could be used for various applications without a significant risk of creating a flammable atmosphere. In one embodiment, the compositions may consist essentially of the indicated components. The term "consist essentially of" means that the compositions of the invention do not contain substantially any other component, in particular any additional (hydro)(fluoro) compounds (e.g., (hydro)(fluoro)alkanes or (hydro)(fluoro)alkenes) known to be used in heat transfer compositions. The term "consist of" is included within the meaning of "consist essentially of." In one embodiment, the compositions of the invention are substantially free of any component having heat transfer properties (other than the specified components). For example, the compositions of the invention may be substantially free of any other hydrofluorocarbon compound. In substantially not and substantially free from, it is included that the compositions of the invention contain 0.5% by weight or less of the indicated component, preferably 0.1% or less, based on the total weight of the composition. The compositions of the invention can be azeotropic or almost azeotropic, preferably azeotropic. Azeotropic composition includes the meaning of a composition that, in vapor-liquid equilibrium, has the same composition in both phases and whose boiling point is lower than that of the pure components. All azeotropic compositions of the invention have been found to exhibit a positive deviation from the ideal. Near-azeotropic composition includes the meaning of liquid compositions whose vapor pressure is higher than that of the pure component with the lowest boiling point when measured at an equivalent temperature, but whose equilibrium vapor composition may differ from the liquid composition. All the chemicals described herein are commercially available. For example, fluorochemicals can be obtained from Apollo Scientific (UK) and carbon dioxide can be obtained from liquefied gas suppliers such as Linde AG. As used herein, all percentage quantities mentioned in the compositions herein, including in the claims, are by weight based on the total weight of the compositions, unless otherwise stated. The term approximately, as used in relation to numerical values ​​of component quantities in % by weight, includes the meaning of ± 0.5% by weight, for example ± 0.2% by weight or ± 0.1% by weight. For the avoidance of doubt, it should be understood that the upper and lower values ​​established for the component quantity ranges in the compositions of the invention described herein may be interchanged in any way, provided that the resulting ranges are within the broader scope of the invention. The compositions of the invention have zero ozone depletion potential. The goal is to have the GWP as low as possible, while respecting other restrictions on flammability, performance, and operating temperature range. The compositions have a GWP of less than 7400, such as less than 5000, less than 4000 or preferably less than 3700. The compositions advantageously have a GWP of less than 3000, less than 2500, less than 2000, less than 1500 or even less than 1000. Typically, the compositions of the present invention have a reduced risk of flammability compared to R-1132a. Flammability can be determined in accordance with ASHRAE Standard 34:2016, which incorporates ASTM Standard E-681 with the test methodology according to Annex 34p of 2004, the full content of which is incorporated herein by reference. In some embodiments, the compositions have one or more of (a) a higher lower flammability limit; (b) a higher ignition energy (sometimes referred to as auto-ignition energy or pyrolysis); or (c) a lower flame speed compared to R1132a alone. Preferably, the compositions of the invention are less flammable compared to R-1132a in one or more of the following respects: lower flammability limit at 23°C; lower flammability limit at 60°C; width of the flammability range at 23°C or 60°C; auto-ignition temperature (thermal decomposition temperature); minimum ignition energy in dry air; or flame speed. The flammability limits are determined in accordance with the methods specified in ASHRAE Standard 34:2016, and the auto-ignition temperature is determined in a 500 ml glass flask by the method of ASTM E659-78. In a preferred embodiment, the compositions of the invention are nonflammable. For example, the compositions of the invention are nonflammable at a test temperature of 60°C using the ASHRAE methodology. Advantageously, vapor mixtures existing in equilibrium with the compositions of the invention at any temperature between approximately -40°C and 60°C are also nonflammable. IVIA / a / ZUZÓ / UI U4 / U In some applications, it may not be necessary for the formulation to be classified as non-flammable by the ASHRAE methodology; it is possible to develop fluids whose flammability limits are reduced sufficiently in air to be safe for use in the application, for example, if it is not physically possible to prepare a flammable mixture due to leakage of the refrigeration equipment charge into the surroundings. In one embodiment, the compositions of the invention have a flammability classifiable as 1 or 2L according to the ASHRAE classification method, indicating non-flammability (class 1) or a weakly flammable fluid with a flame speed of less than 10 cm / s (class 2L). Temperature glide can be managed within a system, and glides of less than approximately 10 K are acceptable with only minor effects on performance. Slips greater than approximately 10 K can cause some degradation in expected performance unless the heat exchangers are designed to accommodate the glide effect. A composition of the invention preferably has a temperature glide in an evaporator or condenser of less than approximately 10 K, even more preferably less than approximately 7 K, such as less than approximately 5 K (for example, less than 3 K). “Temperature glide” is the term given to the temperature change experienced during the evaporation or condensation of a non-azeotropic refrigerant mixture. The critical temperature of a heat transfer mixture must be higher than the maximum expected condenser temperature. This is because cycle efficiency typically decreases as the critical temperature is approached. As this occurs, the latent heat of the refrigerant is reduced, and therefore more heat is dissipated in the condenser by cooling the gaseous refrigerant; this requires more surface area per unit of heat transferred. The critical temperature of R-508B is approximately 11°C, and the critical temperature of R-23 is approximately 26°C. In one aspect, the compositions of the invention have a critical temperature greater than approximately 0 °C, preferably greater than approximately 10 °C, more preferably greater than approximately 25 °C. The compositions of the invention typically have a volumetric cooling capacity that is at least 85% of that of R-23 under comparable cycle conditions. Preferably, the compositions of the invention have a volumetric cooling capacity that is at least 90% of that of R-23, for example, from approximately 95% to approximately 120% (for example, approximately 96% to approximately 115%) of that of R-23. IVIA / a / ZUZÓ / UI U4 / U The compositions of the invention, when used as refrigerants, are typically capable of achieving temperatures of -60 °C or lower, preferably -70 °C or lower, for example -80 °C or lower, while maintaining the evaporation pressure above atmospheric pressure. In one embodiment, the cycle efficiency (Coefficient of Performance, COP) of the compositions of the invention is at least 95% and / or within approximately 5% of the existing refrigerant it is replacing (e.g., R-23). Conveniently, the compressor discharge temperature of the compositions of the invention is within approximately 15 K of the existing refrigerant fluid it is replacing, preferably approximately 10 K or even approximately 5 K. The compositions of the invention are typically suitable for use in existing equipment designs, for example, low-temperature refrigeration equipment, and are compatible with all classes of lubricants currently used with established HFC refrigerants. They can optionally be stabilized or made compatible with mineral oils through the use of appropriate additives. Preferably, when used in heat transfer equipment, the composition of the invention is combined with a lubricant. Conveniently, the lubricant is selected from the group consisting of mineral oil, silicone oil, polyalkylbenzenes (PABs), polyol esters (POEs), polyalkylene glycols (PAGs), polyalkylene glycol esters (PAG esters), polyvinyl ethers (PVEs), poly(alpha-olefins), and combinations thereof. PAGs and POEs (particularly the latter) are currently preferred lubricants for the compositions of the invention. Advantageously, the lubricant further comprises a stabilizer. The lubricant may also preferably comprise pentane (e.g., n-pentane or isopentane). The pentane may be present in an amount of approximately 1 to approximately 10% by weight, such as approximately 2 to approximately 6% by weight of the refrigerant charge (e.g., a composition containing the pentane, the lubricant, and the heat transfer composition). Preferably, the stabilizer is selected from the group consisting of diene-based compounds, phosphates, phenolic compounds and epoxides and their mixtures. Conveniently, the composition of the invention can be combined with a flame retardant. Advantageously, the flame retardant is selected from the group consisting of tri-(2-chloroethyl)-phosphate, (chloropropyl)phosphate, tri-(2,3-dibromopropyl)-phosphate, tri-(1,3-dichloropropyl)-phosphate, diammonium phosphate, various halogenated aromatic compounds, antimony oxide, trihydrate IVIA / a / ZUZÓ / UI U4 / U of aluminum, polyvinyl chloride, a fluorinated iodocarbon, a fluorinated bromocarbon, trifluoroiodomethane, perfluoroalkyl amines, bromofluoroalkylamines and mixtures thereof. In one embodiment, the invention provides a heat transfer device comprising a composition of the invention. Preferably, the heat transfer device is a cooling device. Conveniently, the heat transfer device is an ultra-low temperature refrigeration system, like a forced-air freezer. Advantageously, the heat transfer device contains a cascade system. The invention also provides for the use of a composition of the invention in a heat transfer device as described herein. According to a further aspect of the invention, a method for cooling an article is provided comprising condensing a composition of the invention and then evaporating said composition in the vicinity of the article to be cooled. According to another aspect of the invention, a method for heating an article is provided comprising condensing a composition of the invention in the vicinity of the article to be heated and then evaporating said composition. According to another aspect of the invention, a method is provided for extracting a substance from biomass comprising contacting the biomass with a solvent comprising a composition of the invention and separating the substance from the solvent. According to another aspect of the invention, a method is provided for cleaning an article comprising contacting the article with a solvent comprising a composition of the invention. According to a further aspect of the invention, a method is provided for extracting a material from an aqueous solution comprising contacting the aqueous solution with a solvent comprising a composition of the invention, and separating the material from the solvent. According to another aspect of the invention, a method is provided for extracting a material from a particulate solid matrix comprising contacting the particulate solid matrix with a solvent comprising a composition of the invention and separating the material from the solvent. According to another aspect of the invention, a method is provided for retrofitting a heat transfer device comprising the step of removing an existing heat transfer fluid and introducing a composition of the invention. Preferably, the heat transfer device is a refrigeration device; more preferably, the device is an ultra-low temperature refrigeration system, such as a forced-air freezer. Preferably, the refrigeration system cools a compartment to less than IVIA / a / ZUZÓ / UI U4 / U of approximately -55 °C, preferably to less than approximately -60 °C, more preferably to less than approximately -85 °C, or even to less than -90 °C. Advantageously, the method also includes the step of obtaining an allocation of greenhouse gas emission credits (e.g., carbon dioxide). According to the retrofitting method described above, an existing heat transfer fluid can be completely removed from the heat transfer device before introducing a composition of the invention. Alternatively, an existing heat transfer fluid can be partially removed from a heat transfer device, followed by the introduction of a composition of the invention. The compositions of the invention can also be prepared simply by mixing R-1132a, carbon dioxide, R-125, and the fourth component (and additional components such as a lubricant, stabilizer, or flame retardant) in the desired proportions. The compositions can then be added to a heat transfer device (or used in any other manner as defined herein). In another aspect of the invention, a method is provided for reducing the environmental impact arising from the operation of a product comprising an existing compound or composition. The method comprises at least partially replacing the existing compound or composition with a composition of the invention. Preferably, this method includes the step of obtaining a greenhouse gas emission credit allocation. Environmental impact includes the generation and emission of greenhouse gases through the operation of the product. As mentioned earlier, this environmental impact can be considered to include not only emissions of compounds or compositions that have a significant environmental impact due to leaks or other losses, but also the carbon dioxide emissions resulting from the energy consumed by the device during its operational life. This environmental impact can be quantified using the measure known as Total Equivalent Warming Impact (TEWI). This measure has been used to quantify the environmental impact of certain stationary refrigeration and air conditioning equipment, including, for example, supermarket refrigeration systems (see, for example, http: / / en.wikipedia.org / wiki / Total equivalent warming impact). It can also be considered that the environmental impact includes greenhouse gas emissions arising from the synthesis and manufacturing of the compounds or compositions. In this case, manufacturing emissions are added to energy consumption and direct loss effects to produce the measure known as Life Cycle Production Carbon (LCCP; see, for example, http: / / www.sae.org / events / aars / presentations). IVIA / a / ¿U¿ó / UI U4 / U / 2007papasavva.pdf). The use of LCCP is common in the environmental impact assessment of automotive air conditioning systems. Emission credits are granted for reducing emissions of pollutants that contribute to global warming and can be deposited, traded, or sold. They are conventionally expressed as the equivalent amount of carbon dioxide. Therefore, if the emission of 1 kg of R-23 is avoided, an emission credit of 1 x 14,800 = 14,800 kg of CO2 equivalent can be granted. In another embodiment of the invention, a method is provided for generating greenhouse gas emission credit(s) comprising (i) replacing an existing compound or composition with a composition of the invention, wherein the composition of the invention has a lower GWP than the existing compound or composition; and (ii) obtaining greenhouse gas emission credit for such replacement step. In a preferred embodiment, the use of the composition of the invention results in the equipment having a lower total equivalent heating impact and / or lower carbon production life cycle than would be obtained by using the existing compound or composition. These methods can be applied to any suitable product, for example, in the fields of air conditioning, refrigeration (e.g., low and medium temperature refrigeration), heat transfer, gaseous dielectrics, flame suppression, solvents (e.g., vehicles for flavorings and fragrances), cleaners, topical anesthetics, and expansion applications. Preferably, the field is ultra-low temperature refrigeration. Examples of suitable products include heat transfer devices, solvents, and mechanical power generation devices. In a preferred embodiment, the product is a heat transfer device, such as a refrigeration device or an ultra-low temperature refrigeration system. The existing compound or composition has an environmental impact, as measured by GWP and / or TEWI and / or LCCP, that is higher than the composition of the invention that replaces it. The existing compound or composition may comprise a fluorocarbon compound, such as a perfluoro, hydrofluoro, chlorofluoro, or hydrochlorofluorocarbon compound, or may comprise a fluorinated olefin. Preferably, the existing compound or composition is a heat transfer compound or composition such as a refrigerant. Examples of refrigerants that can be replaced include ULT refrigerants such as R-508A, R-508B, R-23, and R-13B1. Any amount of the existing compound or composition can be replaced to reduce environmental impact. This may depend on the environmental impact of the existing compound or composition being replaced and the environmental impact of the composition. IVIA / a / ZUZÓ / UI U4 / U replacement of the invention. Preferably, the existing compound or composition in the product is completely replaced by the composition of the invention. The invention is illustrated by the following non-limiting examples. Examples Compositions of R-1132a, R-744, R-125 and R-23 The performance of the quaternary compositions of the invention was modeled, and the results are provided in the following tables. The tables list the GWP, condenser and evaporator slip, capacity and COP relative to R-23, discharge temperature difference, and condenser pressure. The tables provide contents as weight percentages unless otherwise specified. The cycle conditions used in the modeling are as shown in Table 1. Table 1 IVIA / a / ZUZÓ / UI U4 / U Cycle conditions for modeling: The reference fluid for cycle calculation is R-23. Condensation temperature °C -20. Evaporation temperature °C -70. Suction gas temperature °C -50. Isentropic efficiency 0.65. Subcooling K 5. Evaporator superheat K 5. Cooling capacity kW 1. Removal ratio 0.03. Suction line diameter for PD calculation mm 22. Cycle calculation results: Reference R-23. Pressure ratio 7.20. Volumetric efficiency 89.3%. Condenser slip K 0.0. Evaporator slip. Evaporator inlet temperature K 0.0 °C -70.0 Condenser outlet temperature °C -25.0 Condenser pressure bar 13.95 Evaporator pressure bar 1.94 Cooling effect kJ / kg 174.1 Coefficient of performance 1.90 Discharge temperature °C 86.4 Mass flow rate kg / h 20.7 Volumetric flow rate m3 / h 2.72 Volumetric capacity kJ / m3 1322 Suction line pressure drop kPa / m 8.75 Suction line density kg / m3 7.59 Condenser inlet density kg / m3 58.94 Capacity relative to R-23 100.0% COP relative to R-23 100.0% Discharge temperature difference K 0.0 Condenser pressure difference bar 0.00 Pressure ratio relative to 100.0% of R-23 The thermodynamic model used for the mixture calculations employs a cubic equation of state to model the vapor phase, with a Gibbs free energy correlation (the Wilson equation) to model the liquid phase and temperature correlations of the component vapor pressures. Binary interaction parameters for the fluids were correlated with measured phase equilibrium data when available. 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CO 7: CD n / bm n / eznz / Β / γΐΛΐ o lo ιο o CXJ i- CXJ T— |x Jx x° , o oj (O cxi < r< ° °^ oh 05 CXJ co · CXJ oo < ° 05 05 oooo Tt co CX1 T-- 05 1- sP 05 r- " s ai cót L ° lo / g— 1 00 T- T- CO CXJ CO -P -PO 05 £ CO <0 f 05 P CXI CÓ < *" θ ooooo CO CXJ T- I- xF xt >5 -A 05 00 00 - CXJ ° ” 2 co 2 σ5 O θ θ C X— LO O T 05 £ CO <0 f 05 P CXI CÓ < *" l·'·' 5 °° OÓ OT f -ta 05 01 05 O LO O LO 'd- oo i- i— co x° χθ l·* en g CO <0 g <0 CM ¢ § oó θ O LO LO O si- 00 1- CO x P 1-too CXJ o |< 05 00 LO OC\1 CXJ T- CXJ 1- 'í CO x° CO CXJ g «i «5 o ^5 o, CXJ 00 < 01 05 CO U- 00 CXJ Tt CXJ Clico lo co oo LO «S en m 00 V0 CO50 00 CXJ tF CO CXJ T- CO O >θ 00 00 · · o cP · 1 f*\ J0 00 °> O 05 £ §5 °° θ' 05 co o r-· o CO 00 · or in r\i O LO u.05 CXJ CO < T” ° oí 00 LO N LO 'sF CO T— CXJ 'si- OO -° co co C° cono ° 0 |< xr lo 10 co cxi g oó LO LO LO LO xf CXJ CXJ V l> δ? ” g 5 σ> <0 05 o 000-050. n / bm n / eznz / Β / γΐΛΐ lo lo lo lo CO CU π- CU CD i- OO m · · ° Cr* · O ω c° Ό „ LO ” s S LO O LO OOOT Od i— Γ^. χθ χΟ T— CU < < ° 6 lO in rx o 1005 in LO LO LO CO CO >- I- <£> 00 00 χ° OO 0 ¡x) ID CD <m LO cu <N r< Y Oí LO O LO O CO Tt 1- > - T— (x CD x° fx 1— . . ox 3- . LO W (O cu co rx ° o> LO OO LO OOT CM m ω d- co . r» · .o^o^ g Oí Oí „ CU 8 oí o> LO LO OO co co CU t— σ> σ> χ LO CO V T- 1- C0 'd CO xp \PO or LO<D oo CM 0X1 cu o¿ ° en LO LO O O co v ·> - >- >- co σ> -yx° co S * V CM § 3 LO LO LO LO OO CX1 o lo cq χθ χθ ω ¿o σί σ><jy o o T- c\j Ó σ> o momo co 'd- c\j - - ¿5 O% " °0 00 <η<d ° σ> LO LO LO CO V >- C0 CD O) 'sO χθ co t Ci · o C)XC\J eo CO CO ° 8 oí 2 Oí LO O LO O CO LO t—— O 1- x° X° LO g LO LO CU C\J ° g OÍ o OÍ O LO O LO v cu cu <D CO CO x? x° 00 g OÍ σί σ, C0 0X1 g 00 05 en 0.08 1.45 0.83 0.23 -0.35 1.59 0.95 0.34 -0.25 1.70 1.05 0.44 -0.16 Compositions of R-1132a, R-744, R-125 and R-116 The performance of the quaternary compositions of the invention was modeled, and the results are provided in the following tables. The tables list the GWP, condenser and evaporator slip, capacity and COP relative to R-23, the difference in discharge temperature and condenser pressure, the maximum VDF in vapor and liquid, and the molar percentage of R-1132a. The tables show contents as weight percentages unless otherwise specified. The conditions used are those established in Table 1. IVIA / a / ZUZÓ / UI U4 / U O LO O LO LO C\J ί- i- 20 co i- co Y σ> +ri< m CO Γ- 00 co co cr> O LO LO O LO OJ -r- i- T— CO CD Ά 1— H- " LO co ° cxi<N CO ° ™ O> oooo LO CO t— i- 1- C\l C\J -O CO £ ¿ ° 2 σ> OO LO LO LO CO 1- CO CO O Ύ O CO § ” + » ® + 5 ” ct> O LO O LO LO CO T- co ω n ω n ω co co „ co £ oí $3 σ> OO LO LO lo +r CO <n>o Y CD Ckl ¡5 co co L. lo V CD fT) ™ σ> Table 3 R744 60 R1132a 30 R116 5 R125 5 Global warming potential (AR4 basis) 786 Cycle calculation results Condenser slip K 2.9 Evaporator slip K 3.3 Capacity relative to R-23 130.8 % COP relative to R-23 98.7 % Discharge temperature difference K 12.9 Condenser pressure difference bar 4.05 n / bm n / eznz / Β / γΐΛΐ 00 LO LO LO t WT T- 21 co oo cxi χ° + σ> σ> __ . cr- cr· r~in σ> cm 9 <N 00 O 1- O t— 1— CO LO 00 Ttoj N CO + + tJ) 00 00 i< rri L ° on <x>co <p 00 . c\1 co o i- o i- 1"" co lo ’sj- c\j t— 1- ct>LO fr; < LO 00 00 ° 00 LO u? :<N CT¡ O ™ > - OT— T— LO O LO O Ti CO C\JT— CD LO <> ^0 r^- l·*- qq 00 O jjj θ 00 >- VO Τ- Ο o Ί- T~ LO OO LO 00 T- 1- LO C\1 00 >5 >5 C\J o £ i< co f - A - £ o 1- O LO O LO O CO -i- i- >— LO <£> LO i- 00 LO LO 1-2° LO LO LO C\JV<N ,-0173 C\1 o Ί~ Ί- LO LO LO LO CO CO O 00 > θ LO OC*S t— LO Γ- ó CD i- σ> Ί- 00 LO N I 'sf- 00 i" oi— o >5 >ξ c\j oo 00 < CÓ T- ° co °° LO O Ó Ó T- 1- O LO LO OO Tt 00 i- I- CXJ -~o sP 00 00 κ. · OO · f λ m co „ σ, o ώ O) i- σ> i— LO LO LO LO Tt 00 T- LO LO O >° LO LO § có<N CD O ° (XI o T— T— LO O O LO ^f· > — CD CO C\| O ZT"» · · OO · v4- CO CO oo o O ί— CD OC\J o Ί- T~ OOOO LO C\J t— C\JT— C0 O 'χθ Χθ Ί— O) σί ω o ω T— CO O) OO) Ί- OO LO LO LO CM ·>- 1- LO C\JV LO LO LO >< CÓ ° ° ΛΙ ω CO °ο O<n L^ · C\1 G σ> w >- CD Ί- oooo LO C\JC\J i— t—COO>>o>°C\1t— ? THE<D ω Ó % £¡ ώ σϊ ' ” c\i σ> the- n / bm n / eznz / Β / γΐΛΐ ιο ιο oo CO sT i- i- >- co cxi j i- en LO ω ω N ω T- CO d 1- O Y- 1— LO LO LO LO CO CO C\1 co cxi en j sP en cxj co ° rX oj xr oo co . swollen- . O) oi— LO O LO O CO CXJ r- χ° co cd · . Cr' Cr* . λα co 00 o co 2 »— ó doo Y- T— LO LO LO LO CO 'Φ >- CD t— Γ-» xp xP LO CO < < ° ° O 00 lo co . T- LO OOO Ί- Ί— LO O LO O CO LO 1- Tt- 00 JJ 00 O £ LO LO ít CO 1- Ó τι- O oooo 'd- co -i- cu τ-Οπ-χΟχΟΟΟ··gj o σú o σ o χ~ Ί- OO LO LO Xf- CO 1- 1- co l·*- xp xp CO CO lo < ° ° in (Y) co LY) OQ cxj cxj d t- i- o Ί- Ί- oooo 'sf- CO C\1 i— i- CD σ> χθ χθ CO CO LO LO O Tt CO C\1 - r> LO 5° O CO C9 QO LO d cxj doo Ί- 1— O LO O LO Tt CO T- CD C0 C0 χθ χθ CO ^J- < co CU Γχ OO CXJ -r- dd 1- O Y- LO T— O S - O CO - C 0 - CD — CD xp OT— CO LO C0 g, i LO £ CXJ dd 1- O Ί~ Ί- CO LO O CXJ xT C\l T- CXJ T— CO r^- xp xp CXJ h* σ) f—J ° ° y—i O) QJ O) O o oo o .ddoo Ί- Ί- CO LO CM O CXJ i- CXJ LO O CO >? >? I- co CD fX η ° ° CO t— en o jj> oq -η- C\J ώ ó *” oo Ί-- T-- CO LO 't co Si- OJ 1- 1- en oo jjo CO O o N CXl bc\ioo *” 1— O I- Ί-. n / bm n / eznz / Β / γΐΛΐ LO LO LO LO 00 CU CU co en oí + co co ° O CM ζ. 00 CM Μ ώ W ' ° en o 1— LO O LO O co co cxi 1- CM LO χ° χ° 00 σ> 00 m r-; ° ° rn 00 lo ow ω ® CM AA ° OO LO LO LO CO CO T- t” CO LO x° x° T- CM LO rx¿ en eh 10 co 00 oo co °° CM (ji *" OO T- T— LO O LO O CO 'sf 1— 1— i- LO M - X LO - CD LO 1 CD OO LO 00 00 T- CM CO CO CO X° x° CM Tf· σ> H ° ° eri O o θ O co CM CM ° σι o Ί- LO LO OO CO CO CM i- oo χ° σ> co £ cS o lo CU ΊΟ o Ί~ O- LO - CO- Μ - CO- Ί > cu . co < co LfS r»* co qo en «— ooo Ί- Ί- In summary, the compositions of the invention exhibit an unexpected combination of advantageous properties such as (i) low or non-flammability, (ii) low GWP compared to existing ultra-low temperature refrigerants (e.g., R-23), and (iii) comparable or improved cooling performance at suitable operating temperatures and pressures compared to existing ultra-low temperature refrigerants (e.g., R-23) in terms of, e.g., low cooling capacity and / or glide and / or energy efficiency. Preferences and options for a particular aspect, feature, or parameter of the invention, unless the context indicates otherwise, should be considered as described in combination with any preferences and options for all other aspects, features, and parameters of the invention. The invention is defined by the following claims. < / x> < / n> < / t>

Claims

1. A composition, characterized in that it comprises: (i) 20 to 40 wt% of 1,1-difluoroethene (vinylidene fluoride, R-1132a); (ii) 5 to 70 wt% of carbon dioxide (CO2, R-744); (iii) 1 to 50 wt% of pentafluoroethane (R-125); and (iv) 1 to 50 wt% of trifluoromethane (R-23); wherein the composition has a global warming potential (GWP) of less than 7400, preferably less than 5000, such as less than 3700.

2. The composition according to claim 1, further characterized in that it comprises 25 to 35% by weight of R-1132a.

3. The composition according to claim 1 or 2, further characterized in that it comprises from 10 to 60% by weight of carbon dioxide.

4. The composition according to claim 3, further characterized in that it comprises 25 to 60% by weight of carbon dioxide.

5. The composition in accordance with any of the preceding claims, further characterized in that it comprises from 5 to 45% by weight of R-125.

6. The composition according to claim 5, further characterized in that it comprises from 5 to 30% by weight of R-125.

7. The composition according to claim 6, further characterized in that it comprises 10 to 25% by weight of R-125.

8. The composition according to claim 1, further characterized in that it comprises 20 to 40% by weight of R-1132a, 30 to 60% by weight of carbon dioxide, 1 to 20% by weight of R-23 and 1 to 35% by weight of R-125.

9. The composition according to claim 8, further characterized in that it comprises 25 to 35% by weight of R-1132a, 35 to 50% by weight of carbon dioxide, 5 to 15% by weight of R-23 and 5 to 30% by weight of R-125.

10. The composition according to claim 8, further characterized in that it comprises 25 to 30% by weight of R-1132a, 35 to 50% by weight of carbon dioxide, 10 to 25% by weight of R-125 and 5 to 20% by weight of R-23.

11. The composition in accordance with any of the preceding claims, further characterized in that it essentially consists of the indicated components.

12. The composition according to any of the preceding claims, further characterized in that it is azeotropic or almost azeotropic.

13. The composition according to any of the preceding claims, further characterized in that the composition is less flammable than R-1132a alone. IVIA / a / ZUZÓ / UI U4 / U 14. The composition according to claim 13, further characterized in that the composition has: a. an upper flammability limit; b. a higher ignition energy; and / or c. a lower flame velocity compared to R-1132a alone.

15. The composition in accordance with any of the preceding claims, further characterized in that it is non-flammable.

16. The composition according to any of the preceding claims, further characterized in that it has a temperature glide in an evaporator or condenser of less than 10K.

17. The composition according to claim 16, further characterized in that it has a temperature glide in an evaporator or condenser of less than 7K.

18. The composition in accordance with any of the preceding claims, further characterized in that it has a critical temperature greater than 0°C.

19. The composition according to claim 18, further characterized in that it has a critical temperature greater than 10°C.

20. The composition in accordance with any of the preceding claims, further characterized in that its volumetric cooling capacity is at least 90% of that of R-23 under comparable cycle conditions.

21. The composition according to claim 20, further characterized in that its volumetric cooling capacity is at least 95% of that of R-23 under comparable cycle conditions.

22. The composition in accordance with any of the preceding claims, further characterized in that its cycle efficiency (Coefficient of Performance, COP) is at least 95% and / or within 5% of the existing refrigerant it is replacing.

23. The composition in accordance with any of the preceding claims, further characterized in that its compressor discharge temperature is within 15K of that of R-23 under comparable cycle conditions.

24. A composition, characterized in that it comprises a lubricant and a composition as claimed in any of the preceding claims.

25. The composition according to claim 24, further characterized in that the lubricant is selected from mineral oil, silicone oil, polyalkylbenzenes (PABs), polyol esters (POEs), polyalkylene glycols (PAGs), polyalkylene glycol esters (PAG esters), polyvinyl ethers (PVEs), poly(alphaolefins), and combinations thereof. IVIA / a / ZUZÓ / UI U4 / U 26. The composition according to claim 25, further characterized in that the lubricant is selected from PAGs or POEs.

27. The composition according to claim 26, further characterized in that the composition additionally comprises pentane.

28. A composition, characterized in that it comprises a stabilizer and a composition as claimed in any of the preceding claims.

29. The composition according to claim 28, further characterized in that the stabilizer is selected from diene-based compounds, phosphates, phenolic compounds and epoxides and mixtures thereof.

30. A composition, characterized in that it comprises a flame retardant and a composition as claimed in any of the preceding claims.

31. The composition according to claim 30, further characterized in that the flame retardant is selected from the group consisting of tri-(2-chloroethyl)-phosphate, (chloropropyl) phosphate, tri-(2,3-dibromopropyl)-phosphate, tri-(1,3-dichloropropyl)-phosphate, diammonium phosphate, various halogenated aromatic compounds, antimony oxide, aluminum trihydrate, polyvinyl chloride, a fluorinated iodocarbon, a fluorinated bromocarbon, trifluoroiodomethane, perfluoroalkyl amines, bromofluoroalkyl amines and mixtures thereof.

32. Use of a composition as claimed in any of the preceding claims in forced-air freezing equipment, wherein the temperature achieved using the composition is -80°C or less.

33. A heat transfer device, characterized in that it contains a composition as claimed in any of claims 1 to 31.

34. The heat transfer device according to claim 33, further characterized in that the heat transfer device is a cooling device.

35. The heat transfer device according to claim 33 or 34, further characterized in that the heat transfer device comprises an ultra-low temperature cooling system.

36. The heat transfer device according to claim 35, further characterized in that the heat transfer device is a forced air freezer.

37. The heat transfer device according to any of claims 33 to 36, further characterized in that the heat transfer device comprises a cascade system. IVIA / a / ¿U¿ó / UI U4 / U 38. A method for cooling an article, characterized in that it comprises condensing a composition as claimed in any of claims 1 to 31 and then evaporating the composition in the vicinity of the article to be cooled.

39. A method for heating an article, characterized in that it comprises condensing a composition as claimed in any of claims 1 to 31 in the vicinity of the article to be heated and then evaporating the composition.

40. A method for extracting a substance from a biomass, characterized in that it comprises contacting the biomass with a solvent comprising a composition as claimed in any of claims 1 to 31, and separating the substance from the solvent.

41. A method for cleaning an article, characterized in that it comprises contacting the article with a solvent comprising a composition as claimed in any of claims 1 to 31.

42. A method for extracting a material from an aqueous solution or a particulate solid matrix, characterized in that it comprises contacting the aqueous solution or the particulate solid matrix with a solvent comprising a composition as claimed in any of claims 1 to 31, and separating the material from the solvent.

43. A method for retrofitting a heat transfer device, characterized in that it comprises the step of removing an existing heat transfer composition and introducing a composition as claimed in any of claims 1 to 31.

44. The method according to claim 43, further characterized in that the heat transfer device is a cooling device.

45. The method according to claim 44, further characterized in that the heat transfer device is an ultra-low temperature refrigeration system.

46. ​​The method according to claim 45, further characterized in that the cooling system cools a compartment to less than -60°C.

47. The method according to claim 46, further characterized in that the cooling system cools a compartment to less than -70°C.

48. A method for reducing the environmental impact arising from the operation of a product comprising an existing compound or composition, the method being characterized in that it comprises at least partially replacing the existing compound or composition with a composition as claimed in any of claims 1 to 31.

49. A method for generating greenhouse gas emission credits, characterized in that it comprises (i) replacing an existing compound or composition with a composition as claimed in any of claims 1 to 31, wherein the composition as claimed in any of claims 1 to 31 has a lower GWP IVIA / a / ZUZÓ / UI U4 / U than the existing compound or composition; and (ii) obtaining greenhouse gas emission credits for such replacement step.

50. The method as claimed in claim 49, further characterized in that the use of the composition of the invention results in a lower Total Equivalent Warming Impact and / or a lower Carbon Production Life Cycle than that achieved by using the existing compound or composition.

51. The method according to claim 48, further characterized in that it is carried out on a product from the fields of air conditioning, refrigeration, heat transfer, gaseous dielectrics, flame suppression, solvents, cleaners, topical anesthetics and expansion applications.

52. The method according to claim 48 or 51, further characterized in that the product is selected from a heat transfer device or a solvent.

53. The method according to claim 52, further characterized in that the product is a heat transfer device.

54. The method according to claim 53, further characterized in that the product is an ultra-low temperature refrigeration system.

55. The method according to any of claims 48 to 54, further characterized in that the existing compound or composition is a heat transfer composition.

56. The method according to claim 55, further characterized in that the heat transfer composition is a refrigerant selected from R-508A, R-508B, R-23 and R-13B1.