Azeotrope and azeotrope-like compositions of 1-chloro-1,2 difluoroethylene and 2,3,3,3-tetrafluoroprop-1-ene

Abstract

Provided are azeotropic or azeotrope-like compositions comprising 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropene (HFO-1234yf) and uses thereof.

Description

Invention Field

[0001] This invention relates to azeotropic and azeotropic compositions comprising 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropylene (HFO-1234yf) and their uses.

[0002] background

[0003] Fluorocarbon-based fluids are widely used in industry for many applications, including as refrigerants, aerosol propellants, foaming agents, heat transfer media, and gaseous dielectrics. Due to the questionable environmental concerns associated with some of these fluids, including their relatively high global warming potential, there is a desire for fluids with low or even zero ozone depletion potential. Furthermore, there is a desire for single-component fluids or azeotropic mixtures that do not fractionate upon boiling and evaporation. Safety concerns such as flammability may also limit the widespread adoption of refrigerants in commercial and residential applications. Selecting refrigerants for vapor compression HVAC&R systems requires a balance between performance, safety, and environmental impact. However, finding safe, environmentally friendly novel non-fractionated mixtures is complex because azeotropic formation is difficult to predict.

[0004] The industry has been searching for new blends based on fluorocarbons that offer alternatives and are considered more environmentally friendly alternatives to CFCs and HCFCs.

[0005] The Montreal Protocol, designed to protect the ozone layer, mandates the phase-out of chlorofluorocarbons (CFCs). More ozone-friendly materials, such as hydrofluorocarbons (HFCs), like HFC-134a, have replaced CFCs. These latter compounds are proven greenhouse gases that contribute to global warming and are regulated under the Kyoto Protocol on Climate Change. Emerging alternatives, hydrofluoroolefins, demonstrate environmental acceptability due to their zero ozone depletion potential (ODP) and acceptablely low GWP.

[0006] The purpose of this invention is to provide novel compositions that can be used as refrigerants, heat transfer fluids, foaming agents, solvents, etc., which have unique properties compared to current HFCs and can meet the requirements of low or zero ozone depletion potential and lower global warming potential.

[0007] Brief description of the attached figures

[0008] Figure 1 The gas-liquid equilibrium diagrams for HFO-1122a and R-1234yf were obtained using the COSMO-RS 2015 modeling method.

[0009] Figure 2 The gas-liquid equilibrium diagrams for HFO-1122a and R-1234yf were obtained using the COSMO-RS 2017 modeling method.

[0010] Preferred implementation method detailed

[0011] The inventors have developed several compositions that help meet the ongoing demand for alternatives to CFCs, HCFCs, and HFCs. According to certain embodiments, the present invention provides azeotropic or azeotropic compositions comprising 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropylene (HFO-1234yf).

[0012] The preferred compositions of the present invention tend to be low flammability to non-flammability, while exhibiting low global warming potential (“GWPs”). Therefore, the applicant has recognized that such compositions can be used very advantageously in a number of applications, including as alternatives to CFCs, HCFCs and HFCs (such as HCFC-23, HFC-134a, HFC-245fa, HFC-365mfc, etc.) in refrigerants, aerosols and other applications.

[0013] Furthermore, the applicant was surprised to recognize that azeotropic or azeotropic compositions of 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropylene (HFO-1234yf) can be formed. Therefore, in other embodiments, the present invention provides a method for preparing an azeotropic composition comprising combining 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropylene (HFO-1234yf) in amounts that effectively produce an azeotropic composition.

[0014] Furthermore, the applicant has recognized that the azeotropic compositions of the present invention exhibit properties that make them advantageous for use as refrigerant compositions and as foaming agents. Therefore, in other embodiments, the present invention provides refrigerant compositions and / or foaming agents, as well as solvents, comprising azeotropic compositions of 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropylene (HFO-1234yf).

[0015] Azeotropic compositions

[0016] As used herein, the term "azeotropic-like" is used broadly to include both strictly azeotropic compositions and compositions that behave like azeotropic mixtures. In fundamental terms, the thermodynamic state of a fluid is defined by pressure, temperature, liquid composition, and vapor composition. An azeotropic mixture is a system of two or more components in which the liquid and vapor compositions are equal at specific pressures and temperatures. In practice, this means that the components of an azeotropic mixture are azeotropic and cannot be separated during a phase transition.

[0017] The azeotropic compositions of the present invention may include additional components that do not form a new azeotropic system, or additional components that are not in the first fraction. The first fraction is the first fraction taken after the distillation column has shown steady-state operation under total reflux conditions. One method to determine whether the addition of a component forms a new azeotropic system and is therefore outside the scope of the present invention is to distill a sample of the composition containing that component under conditions intended to separate the non-azeotropic mixture into its individual components. If the mixture containing the additional component is a non-azeotropic mixture, the additional component will be fractionated from the azeotropic components. If the mixture is an azeotropic mixture, a limited amount of the first fraction will be obtained, which contains all the mixture components that are azeotropic or behave like a single substance.

[0018] Therefore, another characteristic of azeotropic compositions is the existence of a series of azeotropic or azeotropic compositions containing different proportions of the same component. All these compositions are intended to be covered by the terms "azeotropic" and "azeotropic." For example, it is well known that the composition of a given azeotrope will vary at least slightly under different pressures, just as the boiling point of the composition will vary. Thus, the azeotropes of A and B represent a unique type of relationship, but with variable compositions dependent on temperature and / or pressure. Therefore, for azeotropic compositions, there exists a series of azeotropic compositions containing different proportions of the same component. All these compositions are intended to be covered by the term azeotropic as used herein.

[0019] It is well known in the art that the formation of azeotropes cannot be predicted. The applicant was surprised to recognize that the combination of 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropylene (HFO-1234yf) can form azeotropic or azeotropic blends.

[0020] According to certain preferred embodiments, the azeotropic or azeotropic-like compositions of the present invention comprise, preferably substantially, effective azeotropic or azeotropic amounts of 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropylene (HFO-1234yf). As used herein, the term "effective azeotropic amount" refers to the amount of each component such that, when combined with other components, it results in the formation of the azeotropic-like composition of the present invention. Preferably, the azeotropic-like compositions of the present invention comprise, preferably substantially, about 99 mol% to about 1 mol% of 1-chloro-1,2-difluoroethylene (R-1122a) and about 1 mol% to about 99 mol% of 2,3,3,3-tetrafluoropropylene (HFO-1234yf). More preferably, the azeotropic composition of the present invention comprises about 10 mol% to about 70 mol% of 1-chloro-1,2-difluoroethylene (R-1122a) and about 30 mol% to about 90 mol% of 2,3,3,3-tetrafluoropropylene (HFO-1234yf), preferably consisting substantially of therefrom. Even more preferably, the azeotropic composition of the present invention comprises about 10 mol% to about 40 mol% of 1-chloro-1,2-difluoroethylene (R-1122a) and about 60 mol% to about 90 mol% of 2,3,3,3-tetrafluoropropylene (HFO-1234yf), preferably consisting substantially of therefrom. Most preferably, the azeotropic composition of the present invention comprises about 40 mol% of 1-chloro-1,2-difluoroethylene (R-1122a) and about 60 mol% of 2,3,3,3-tetrafluoropropylene (HFO-1234yf), preferably consisting substantially of therefrom. Unless otherwise stated, the molar percentages disclosed herein are based on the total number of moles of 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropylene (HFO-1234yf) in the composition.

[0021] The azeotropic compositions of the present invention can be prepared by combining effective azeotropic or azeotropic amounts of 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropylene (HFO-1234yf). Any of the numerous methods known in the art for combining two or more components to form a composition can be applied to the methods of the present invention to produce azeotropic compositions. For example, 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropylene (HFO-1234yf) can be mixed, stirred, or otherwise contacted manually and / or mechanically as part of a batch or continuous reaction and / or process, or through a combination of two or more such steps. Based on the disclosure herein, those skilled in the art will be able to readily prepare the azeotropic compositions according to the present invention without excessive experimentation.

[0022] Composition Additives

[0023] The azeotropic or azeotropic-like compositions of the present invention may also include any one of a variety of optional additives, including stabilizers, metal passivators, corrosion inhibitors, etc.

[0024] In some preferred embodiments, the compositions of the present invention further comprise a lubricant. Any of a variety of conventional lubricants can be used in the compositions of the present invention. An important requirement for the lubricant is that, when used in a refrigeration system, sufficient lubricant must return to the compressor of the system to lubricate the compressor. Therefore, the suitability of a lubricant for any given system depends partly on the characteristics of the refrigerant / lubricant and partly on the characteristics of the system to which it is intended to be used. Examples of suitable lubricants include mineral oils, alkylbenzenes, polyol esters, including polyalkylene glycols, PAG oils, etc. Mineral oils, including paraffinic oils or naphthenic oils, are commercially available. Commercially available mineral oils include WitcoLP 250 (registered trademark) from Witco, Zerol 300 (registered trademark) from Shrieve Chemical, Sunisco 3GS from Witco, and Calumet RO 15 from Calumet. Commercially available alkylbenzene lubricants include Zerol 150 (registered trademark). Commercially available esters include neopentyl glycol dinonanoate, available from Emery 2917 (registered trademark) and Hatcol 2370 (registered trademark). Other useful esters include phosphate esters, diesters, and fluorinated esters. Preferred lubricants include polyalkylene glycols and esters. Certain more preferred lubricants include polyalkylene glycols.

[0025] Use of the composition

[0026] The compositions of the present invention can be used in a wide range of applications. For example, one embodiment of the present invention relates to a refrigerant composition comprising the azeotropic composition of the present invention.

[0027] The refrigerant compositions of the present invention can be used in any of a wide variety of refrigeration systems, including air conditioning, refrigeration, heat pumps, coolers, HVAC systems, etc. In some preferred embodiments, the compositions of the present invention are used in refrigeration systems originally designed to use HCFC or HFC refrigerants (e.g., HCFC-12 or HFC-134a). The preferred compositions of the present invention tend to exhibit many desirable properties of HFC-134a and other HFC refrigerants, including a GWF as low as or lower than that of conventional HFC refrigerants, and a capacity as high as or similar to that of such refrigerants. Furthermore, the relatively constant boiling point characteristics of the compositions of the present invention make them more desirable than some conventional HFCs for use as refrigerants in many applications.

[0028] In some other preferred embodiments, the compositions of the present invention are used in refrigeration systems originally designed to use HFC-refrigerants. Preferred refrigeration compositions of the present invention can be used in refrigeration systems containing lubricants typically used with HFC-refrigerants, such as mineral oils, silicone oils, polyalkylene glycol oils, etc., or can be used with other lubricants typically used with HFC-refrigerants. As used herein, the term "refrigeration system" generally refers to any system or device, or any component or part of such a system or device, that employs a refrigerant to provide cooling. Such refrigeration systems include, for example, air conditioners, refrigerators, coolers, transport refrigeration systems, commercial refrigeration systems, etc.

[0029] Any of the numerous methods for introducing the refrigerant composition of the present invention into a refrigeration system can be used in the present invention. For example, one method includes connecting a refrigerant container to the low-pressure side of the refrigeration system and turning on the refrigeration system compressor to draw refrigerant into the system. In such an embodiment, the refrigerant container may be placed on a scale, thereby allowing monitoring of the amount of refrigerant composition entering the system. Feeding is stopped when the desired amount of refrigerant composition has been introduced into the system. Alternatively, numerous feeding tools known to those skilled in the art are commercially available. Therefore, based on the above disclosure, those skilled in the art will be able to readily introduce the refrigerant composition of the present invention into a refrigeration system according to the present invention without excessive experimentation.

[0030] According to certain other embodiments, the present invention provides a refrigeration system comprising the refrigerant of the present invention and a method for generating heat or cooling by condensing and / or evaporating the composition of the present invention. In some preferred embodiments, the method for cooling articles according to the present invention comprises condensing a refrigerant composition comprising an azeotropic composition of the present invention, and then evaporating the refrigerant composition near the article to be cooled. Some preferred methods for heating articles comprise condensing a refrigerant composition comprising an azeotropic composition of the present invention near the article to be heated, and then evaporating the refrigerant composition. Based on the disclosure herein, those skilled in the art will be able to readily heat and cool articles according to the present invention without excessive experimentation.

[0031] In another embodiment, the azeotropic composition of the present invention can be used alone or in combination with known propellants as a propellant in a sprayable composition. The propellant composition comprises, more preferably substantially comprises, the azeotropic composition of the present invention, and even more preferably comprises, it. The active ingredient to be sprayed along with inert components, solvents, and other materials may also be present in the sprayable mixture. Preferably, the sprayable composition is an aerosol. Suitable active materials to be sprayed include, but are not limited to, cosmetic materials such as deodorants, perfumes, hairsprays, detergents, and polishes, as well as pharmaceutical materials such as anti-asthma and anti-halitosis medications.

[0032] Another embodiment of the invention relates to a foaming agent comprising one or more azeotropic compositions of the present invention. In other embodiments, the invention provides foamable compositions, preferably polyurethane and polyisocyanurate foam compositions, and methods for preparing foams. In such foam embodiments, one or more azeotropic compositions of the present invention are included as foaming agents in the foamable composition, which preferably contains one or more additional components capable of reacting and foaming under suitable conditions to form foam or porous structures, as is known in the art. Any methods known in the art can be used or modified according to the foam embodiments of the present invention.

[0033] Another embodiment of the invention relates to a method for preparing a foamed thermoplastic product, as described below: a foamable polymer composition is prepared by blending the components comprising a foamable polymer composition together in any order. Typically, the foamable polymer composition is prepared by plasticizing a polymer resin and then incorporating the components of a foaming agent composition under initial pressure. A common process for plasticizing polymer resins is thermoplasticization, which involves sufficiently heating the polymer resin to soften it sufficiently for incorporation into the foaming agent composition. Typically, thermoplasticization involves heating the thermoplastic polymer resin to a temperature equal to or close to its glass transition temperature (Tg) or the melting temperature (Tm) of a crystalline polymer.

[0034] Other uses of the azeotropic compositions of the present invention include as solvents, cleaning agents, etc. Examples include vapor degreasing, precision cleaning, electronic device cleaning, dry cleaning, solvent etching cleaning, carrier solvents for depositing lubricants and release agents, and other solvents or surface treatments. Those skilled in the art will be able to readily adapt the compositions of the present invention for such applications without excessive experimentation. Example

[0035] COSMO-RS was used to model refrigerant blends containing the main components cis-HFO-1122a and trans-HFO-1122a to determine the equilibrium liquid and vapor mole fractions at atmospheric pressure and to determine whether azeotropic and / or azeotropic-like mixtures could be obtained using refrigerant R-1234yf. COSMO-RS (Conductor like Screening Model for Real Solvents) is a quantum chemical model used to predict the thermodynamic properties of molecules. Simulation results were obtained using the 2015 and 2017 versions of COSMOtherm, as shown in Table I. Figure 1 and Figure 2As shown. Both parameterizations of the model show no significant difference in boiling points between the cis (Z) and trans (E) isomers of R-1122a. The model shows potential azeotropes between HFO-1122a and R-1234yf with molar ratios of approximately 10 / 90 or 40 / 60, depending on the model parameterization. The isomers of HFO-1122a do not appear to affect the azeotropic ratio. The model shows potential azeotropic combinations between HFO-1122a and R-1234yf with molar ratios ranging from approximately 10 / 90 to 40 / 60.

[0036] Table 1 COSMO-RS 2015 and 2017 Data

[0037]

Claims

1. An azeotropic composition comprising 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropylene (HFO-1234yf), wherein the molar ratio of 1-chloro-1,2-difluoroethylene (R-1122a) to 2,3,3,3-tetrafluoropropylene (HFO-1234yf) is in the range of 10:90 to 70:

30.

2. The azeotropic composition of claim 1, wherein the molar ratio of 1-chloro-1,2-difluoroethylene (R-1122a) to 2,3,3,3-tetrafluoropropylene (HFO-1234yf) is in the range of 10:90 to 40:

60.

3. The azeotropic composition of claim 1, wherein the molar ratio of 1-chloro-1,2-difluoroethylene (R-1122a) to 2,3,3,3-tetrafluoropropylene (HFO-1234yf) is 10 to 90.

4. The azeotropic composition of claim 1, wherein the molar ratio of 1-chloro-1,2-difluoroethylene (R-1122a) to 2,3,3,3-tetrafluoropropylene (HFO-1234yf) is 40 to 60.

5. An azeotropic composition comprising 1-chloro-1,2-difluoroethylene (R-1122a) and 2,3,3,3-tetrafluoropropylene (HFO-1234yf), wherein the molar ratio of 1-chloro-1,2-difluoroethylene (R-1122a) to 2,3,3,3-tetrafluoropropylene (HFO-1234yf) is in the range of 10:90 to 70:30.

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