Mixed refrigerant capable of replacing R134a as well as preparation method and application of mixed refrigerant

Abstract

The invention relates to the technical field of refrigerants, in particular to a mixed refrigerant replacing R134a and a preparation method and application thereof, and the mixed refrigerant comprises a first component, a second component and a third component; the first component is hexafluoropropylene R1216, and the mass ratio of the first component to the hexafluoropropylene R1216 is 36%-65%; the second component is trans-1, 2-difluoroethylene R1132 (E), and the mass ratio of the second component to the first component is 2%-8%; and the third component is 2, 3, 3, 3-tetrafluoropropene R1234yf, and the mass ratio of the third component to the tetrafluoropropene R1234yf is 30%-62%. According to the refrigerant with the three mixed components, the refrigerating capacity per unit volume is higher than that of R134a, the refrigerating performance coefficient is close to that of R134a, excellent system performance is achieved, the GWP value of the mixed refrigerant is smaller than 1 and obviously lower than that of R134a, the requirement for the GWP limit value of an automobile air conditioner refrigerant is met, and the obvious and outstanding environment-friendly advantage is achieved.

Description

Technical Field

[0001] This invention belongs to the field of refrigerant technology, specifically relating to a mixed refrigerant that can replace R134a, its preparation method, and its application. Background Technology

[0002] In recent years, with global warming and ecological degradation, the international community has formulated a series of laws and regulations to restrict the use of refrigerants with high global warming potential (GWP), requiring next-generation refrigerants to have zero ozone depletion potential (ODP) and the lowest possible GWP. In the automotive sector, the most widely used refrigerant for automotive air conditioning in China is 1,1,1,2-tetrafluoroethane (R134a), with a GWP of 1530, exhibiting a very strong greenhouse effect.

[0003] On September 15, 2021, the Kigali Amendment officially came into effect in China. Under the framework of the protocol, my country will implement new requirements for the control of hydrofluorocarbons (HFCs) and include HFCs in the "List of Controlled Ozone-Depleting Substances in China," serving as the legal basis for my country's gradual reduction of HFCs. Traditional automotive air conditioning refrigerant R134a is prominently listed, making its replacement inevitable. In April 2025, my country's Ministry of Ecology and Environment, together with the National Development and Reform Commission and other departments, jointly released the "National Plan for China's Implementation of the Montreal Protocol on Substances that Deplete the Ozone Layer (2025-2030)," requiring that from July 1, 2029, the use of refrigerants with a GWP greater than 150 in the air conditioning systems of newly applied M1 category passenger vehicles will be prohibited. Faced with national control policies, R134a refrigerant, due to its high GWP value, will be phased out. Finding alternative refrigerants with better environmental performance and superior cycle performance than R134a is urgently needed.

[0004] Due to the inherent contradictions between the environmental, flammability, and thermodynamic properties of refrigerants, single refrigerants often cannot meet the current demands of automotive air conditioning systems. Mixed refrigerants, which can balance the thermodynamic properties of refrigerants, have attracted considerable attention. However, a perfect alternative for automotive air conditioning refrigerants has yet to be found. Overcoming the shortcomings of existing technologies and finding automotive air conditioning refrigerants with low GWP values ​​and good thermodynamic properties has become an urgent problem to be solved. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned shortcomings and provide a mixed refrigerant that replaces R134a, with a GWP value of no more than 1, thus having obvious environmental advantages; and with a higher refrigerant per unit volume than the traditional R134a refrigerant and a performance coefficient close to that of R134a refrigerant, thus having broad application prospects in the field of automotive air conditioning, as well as its preparation method and application.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a mixed refrigerant to replace R134a, comprising a first component, a second component and a third component; The first component is hexafluoropropylene R1216, accounting for 36%-65% by mass; The second component is trans-1,2-difluoroethylene R1132(E), accounting for 2%-8% by mass; The third component is 2,3,3,3-tetrafluoropropylene R1234yf, with a mass percentage of 30%-62%.

[0007] Furthermore, the first component accounts for 36-45% of the total mass; The second component accounts for 2% of the total mass. The third component accounts for 53-62% of the total mass.

[0008] Furthermore, the mass percentage of the first component is 40-65%; The second component accounts for 5% of the total mass. The third component accounts for 30%-55% of the total mass.

[0009] Furthermore, the GWP value of the mixed refrigerant is less than 1.

[0010] A method for preparing a mixed refrigerant to replace R134a, characterized in that, for preparing the above-mentioned mixed refrigerant to replace R134a, each component is mixed according to its corresponding mass percentage in... Physical mixing and stirring were carried out at 60℃ and atmospheric pressure (0.1MPa) in the liquid phase to prepare a mixed refrigerant to replace R134a.

[0011] Application of a mixed refrigerant to replace R134a, said mixed refrigerant being used to replace R134a refrigerant in automotive air conditioning systems.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. The three-component mixed refrigerant provided by this invention has a higher volumetric cooling capacity than R134a, and its coefficient of performance is close to that of R134a, exhibiting excellent system performance. Furthermore, the GWP value of the mixed refrigerant is less than 1, significantly lower than that of R134a, meeting the GWP limit requirements for automotive air conditioning refrigerants in the EU's F-gas and the "National Program of China for the Implementation of the Montreal Protocol on Substances that Deplete the Ozone Layer (2025-2030)", thus possessing significant and outstanding environmental advantages. 2. The components of the mixed refrigerant of the present invention contain a large proportion of the highly efficient flame retardant hexafluoropropylene R1216. The mixed refrigerant has good flame retardant properties, which improves the safety performance of the automotive air conditioning system. 3. This invention can be applied to R134a automotive air conditioning systems, which is of great significance for the technological development of automotive air conditioning system refrigerants and for accelerating the phase-out of high GWP refrigerants. Detailed Implementation

[0013] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0014] The components of this invention are commercially available or can be prepared by methods known in the art. The basic material parameters of each component are shown in Table 1. The relative molecular weight (g / mol), standard boiling point (°C), critical temperature (°C), and critical pressure (MPa) were obtained from the refrigerant property lookup REFPROP 10.0 developed by the National Institute of Standards and Technology (NIST). ODP and GWP values ​​are from the United Nations Environment Programme (UNEP) report "2022 REPORT OF THE REFRIGERATION, AIR CONDITIONING AND HEAT PUMPS TECHNICAL OPTIONS COMMITTEE" and the Intergovernmental Panel on Climate Change (IPCC) report "Climate Change 2021: The Physical Science Basis".

[0015] Table 1 Basic physical parameters of each component

[0016] Example 1: The three components, hexafluoropropylene (R1216), trans-1,2-difluoroethylene (R1132(E)) and 2,3,3,3-tetrafluoropropylene (R1234yf), were mixed uniformly at a mass percentage of 36% / 2% / 62% in the liquid phase at -60°C and atmospheric pressure (0.1MPa) to obtain a mixed refrigerant that can replace R134a.

[0017] Example 2: The three components, hexafluoropropylene (R1216), trans-1,2-difluoroethylene (R1132(E)) and 2,3,3,3-tetrafluoropropylene (R1234yf), were mixed uniformly at a mass percentage of 65% / 5% / 30% in the liquid phase at -60°C and atmospheric pressure (0.1MPa) to obtain a mixed refrigerant that can replace R134a.

[0018] Example 3: The three components, hexafluoropropylene (R1216), trans-1,2-difluoroethylene (R1132(E)) and 2,3,3,3-tetrafluoropropylene (R1234yf), were mixed uniformly at a mass percentage of 45% / 2% / 53% in the liquid phase at -60°C and atmospheric pressure (0.1MPa) to obtain a mixed refrigerant that can replace R134a.

[0019] Example 4: The three components, hexafluoropropylene (R1216), trans-1,2-difluoroethylene (R1132(E)) and 2,3,3,3-tetrafluoropropylene (R1234yf), were mixed uniformly at a mass percentage of 37% / 8% / 55% in the liquid phase at -60°C and atmospheric pressure (0.1MPa) to obtain a mixed refrigerant that can replace R134a.

[0020] Example 5: The three components, hexafluoropropylene (R1216), trans-1,2-difluoroethylene (R1132(E)) and 2,3,3,3-tetrafluoropropylene (R1234yf), are mixed uniformly at a mass percentage of 40% / 5% / 55% at room temperature and pressure to obtain a mixed refrigerant that can replace R134a.

[0021] Example 6: The three components, hexafluoropropylene (R1216), trans-1,2-difluoroethylene (R1132(E)) and 2,3,3,3-tetrafluoropropylene (R1234yf), were mixed uniformly at a mass percentage of 45% / 5% / 50% in the liquid phase at -60°C and atmospheric pressure (0.1MPa) to obtain a mixed refrigerant that can replace R134a.

[0022] Example 7: The three components, hexafluoropropylene (R1216), trans-1,2-difluoroethylene (R1132(E)) and 2,3,3,3-tetrafluoropropylene (R1234yf), were mixed uniformly at a mass percentage of 49% / 5% / 46% in the liquid phase at -60°C and atmospheric pressure (0.1MPa) to obtain a mixed refrigerant that can replace R134a.

[0023] Example 8: The three components, hexafluoropropylene (R1216), trans-1,2-difluoroethylene (R1132(E)) and 2,3,3,3-tetrafluoropropylene (R1234yf), were mixed uniformly at a mass percentage of 57% / 5% / 38% in the liquid phase at -60°C and atmospheric pressure (0.1MPa) to obtain a mixed refrigerant to replace R134a.

[0024] 1. The basic thermophysical properties of the mixed refrigerants and R134a refrigerant prepared in Examples 1-8 above, such as standard boiling point and temperature glide (at standard atmospheric pressure), were calculated. The relative molecular weight (g / mol), standard boiling point (°C), bubble point temperature (°C), critical temperature (°C), temperature glide (°C), and critical pressure (MPa) of the refrigerants were obtained by querying or calculating using NIST REFPROP 10.0. GWP 100 The data are from UNEP's "2022 Report of the Refrigeration, Air Conditioning and Heat Pumps Technical Options Committee" and IPCC's "Climate Change 2021: The Physical Science Basis," and the results are shown in Table 2 below: Table 2 Basic physical property parameters of Examples 1-8 and R134a

[0025] As shown in Table 2: (1) The bubble point temperature of the mixed refrigerant provided by the present invention is close to that of the standard boiling point of R134a, and the critical pressure and critical pressure are slightly lower than those of R134a. This indicates that the mixed refrigerant provided by the present invention does not require major changes to the refrigeration and / or heating system and can be used as a long-term substitute for R134a. (2) The mixed refrigerants that replace R134a provided by the present invention have a GWP value of less than 1, which is much lower than the GWP value of R134a. As a replacement refrigerant for R134a, it has a great advantage in terms of environmental protection. (3) The temperature slippage in each embodiment of the present invention is small, which can reduce the adverse effects caused by the temperature slippage of the refrigerant during the operation of the automotive air conditioning system.

[0026] 2. The design operating conditions are based on standard JB / T7666-1995. Under the refrigeration conditions of evaporation temperature -7℃, condensation temperature 43℃, superheat 25℃, subcooling 5℃, and compressor overall efficiency 0.8, the comparison results of the thermodynamic parameters (pressure ratio and discharge temperature) and relative system performance (relative volumetric refrigeration capacity and relative COP of each embodiment relative to R134a) of the above embodiments 1-8 are shown in Table 3: Table 3 Performance comparison results of Examples 1-8 and R134a

[0027] As shown in Table 3: (1) By comparing the performance parameters, it was found that the volumetric cooling capacity of the mixed refrigerant obtained in each embodiment is greater than that of R134a, and the system performance coefficient COP of the mixed refrigerant obtained in each embodiment is also very close to that of R134a, indicating that the mixed refrigerant is feasible to replace R134a in terms of performance. (2) The evaporation pressure and condensation pressure of the mixed refrigerants obtained in Examples 1-8 are not much different from those of R134a. The pressure ratio of the mixed refrigerants obtained in each example is smaller, which helps to improve the efficiency of the compressor. (3) The exhaust temperature of the mixed refrigerants obtained in Examples 1-8 is lower than that of R134a, which improves the overall energy efficiency and effectively ensures the safe operation of the equipment; (4) R1216 is a highly efficient flame retardant. Therefore, it can be estimated that the proportion of the mixed refrigerant contained in the present invention is mainly non-flammable or weakly flammable refrigerant, which increases the safety of system operation and working environment.

[0028] In summary, the mixed refrigerant of the present invention, which replaces R134a, has a higher volumetric cooling capacity than R134a, and its system coefficient of performance (COP) is close to that of R134a. Its outstanding advantage is that the GWP value of the mixed refrigerant is less than 1, which is much lower than that of R134a. It has obvious environmental performance advantages and has very good application effect and development potential when replacing R134a.

[0029] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A mixed refrigerant to replace R134a, characterized in that, It includes the first component, the second component, and the third component; The first component is hexafluoropropylene R1216, accounting for 36%-65% by mass; The second component is trans-1,2-difluoroethylene R1132(E), accounting for 2%-8% by mass; The third component is 2,3,3,3-tetrafluoropropylene R1234yf, with a mass percentage of 30%-62%.

2. The mixed refrigerant to replace R134a according to claim 1, characterized in that, The first component accounts for 36-45% of the total mass; The second component accounts for 2% of the total mass. The third component accounts for 53-62% of the total mass.

3. The mixed refrigerant to replace R134a according to claim 1, characterized in that, The first component accounts for 40-65% of the total mass. The second component accounts for 5% of the total mass. The third component accounts for 30%-55% of the total mass.

4. The mixed refrigerant to replace R134a according to claim 1, characterized in that, The GWP value of the mixed refrigerant is less than 1.

5. A method for preparing a mixed refrigerant to replace R134a according to any one of claims 1 to 4, characterized in that, The components were physically mixed at -60°C and under normal pressure liquid phase according to their respective mass ratios. After stirring evenly, a mixed refrigerant to replace R134a was prepared.

6. An application of a mixed refrigerant as an alternative to R134a according to any one of claims 1 to 4, characterized in that, The mixed refrigerant is used to replace R134a refrigerant in automotive air conditioning systems.

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