KR100682828B1 - Composition of ternary refrigerant mixtures as substitutes for HCFC22 - Google Patents

Abstract

The present invention is a replacement refrigerant for R22, difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a'), A chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition composed of trifluoroiodomethane (CF3I, hereinafter referred to as "13I1").

Difluoromethane. Tetrafluoroethane. Trifluoroiodomethane. Mixed refrigerant composition

Description

Composition of ternary refrigerant mixtures as substitutes for HCFC22}

The present invention is a chlorodifluoromethane replacement (three-way) azeotropic mixed refrigerant composition that can replace chlorodifluoromethane (CClF ₂ H, hereinafter referred to as HCFC22) that has been applied as a refrigerant in heat pumps and various industrial air conditioning equipment It is about. More specifically, difluoromethane (CH ₂ F ₂ , hereinafter referred to as 'HFC-32'), 1,1,1,2-tetrafluoroethane (CH ₂ FCF ₃ , hereinafter referred to as 'HFC-134a') And a chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition composed of trifluoroiodomethane (CF ₃ I, hereinafter referred to as "13I1").

Up to now, Freon system, which has excellent refrigerant characteristics and stability, has been mainly used as a refrigerant for refrigeration equipment, air conditioners, heat pumps, and small-temperature thermal energy use engines. Especially, various industrial air conditioning equipment such as heat pumps and refrigerated warehouses have a boiling point- HCFC22 having a molecular mass of 40.81 DEG C and a molecular mass of 86.47 has been used.

However, as CFC and HCFC compounds are found to be the main cause of the ozone layer destruction and global warming, the production and use of CFC and HCFC compounds are greatly regulated by the Montreal Protocol. This is in progress in two directions: the development of new refrigerants and the study of mixed refrigerants that have the same performance as the regulated refrigerants by mixing existing refrigerants.

The development of new refrigerants is difficult to meet the current regulatory schedule, because a lot of physical and human resources must be mobilized and large-scale production facilities must be in place until they are used as low-priced products. Therefore, the properties of mixed single refrigerants are known, and studies on mixed refrigerants that are easy to apply and commercialize in existing production facilities are being actively conducted. Such mixed refrigerants include large azeotropic mixed refrigerants and azeotropic or azeotropic mixed refrigerants.

An azeotropic mixed refrigerant refers to a refrigerant having a temperature gliding in which two or more refrigerants are mixed to have individual characteristics, and the composition ratio is changed and the temperature is increased or decreased when undergoing isotropic pressure evaporation and condensation.

The biggest problem of these azeotropic mixed refrigerants is that they are classified and separated during evaporation and condensation, which results in undesirable cooling distributions acting unstable to cooling or heating. The use of non-azeotropic mixtures, therefore, sorted during the cooling cycle, adds to the complexity of the system, requiring modifications to the equipment. In the case of using non-azeotropic refrigerants, it is often difficult to replace and repair the cooling system. Also, if the refrigerant leaks in the two-phase state during use or repair, the composition ratio of the mixed refrigerant remaining in the system is changed, and the high vapor pressure component leaks first. Refrigerants with a new composition ratio will be present in the system. Therefore, when refilling due to leakage of the refrigerant, it is not preferable because new refrigerant must be injected after recovering all the refrigerant remaining in the system.

An azeotropic or azeotropic mixed refrigerant refers to a mixed refrigerant in which the gas and liquid component ratios do not change during the isothermal evaporation or condensation process even though two or three pure substances are mixed.

Many azeotropic or azeotropic mixtures possess properties that can be usefully used as substitutes for CFC, HCFC compounds. For example, azeotropic or azeotropic mixtures may have a constant boiling point, thus preventing boiling point variations in processing and use. In addition, when a volume of azeotropic mixture is used as the solvent, the properties of the solvent become constant because the composition of the solvent does not change in the vapor phase. The azeotropic mixture used as the solvent can be conveniently recovered by distillation. The major azeotropic mixed refrigerants used by ASHRAE with a refrigerant number to date are R500, R501, R502, R503, R505, R506, R507, and the like. Three-component azeotrope mixtures of ethanol and nitromethane are disclosed.

Representative mixed refrigerants as substitutes for HCFC-22 include HFC-407C and HFC-410A, which are recommended by the American Society of Refrigeration and Air Conditioning (ASHRAE). HFC-407C is a refrigerant composition in which HFC-32 / 125 / 134a is mixed at 23/25/52 wt% and HFC-410A is a refrigerant composition in which HFC-32 / 125 is mixed at 50/50 wt%.

In addition, US Patent No. 5,080,823 is HFC-143a / propane, US Patent No. 5,211,867 is HFC-125 / 143a, US Patent No. 5,234,613 is HFC-32 / propane, US Patent No. 5,236,611 is PFC-218 / HFC-143a , US Patent No. 5,290,466, HFC-32 / 134a / 134, US Patent No. 5,340,490, HFC-23 / CO 2 and HFC-23 / 116 / CO2, US Patent No. 5,403,504, HFC-125 / 32, US Patent 5,429,740 is HFC-23 / 134a, US Pat. No. 5,538,660 is HFC-32 / HFC-134a / FC-41 and HFC-32 / HFC-134a / PFC-218, US Pat. No. 5,643,492 is HFC-32 / A mixed refrigerant composition comprising 125 / 134a is disclosed. In addition, Japanese Patent Application Laid-Open No. 3-172386, HFC-32 / 125 / 143a, H3-370594, HFC-23 / 125 / 134a, H3-370593, HFC-23 / 125/32, H3-370511 No. HFC-23 / 143a / 134a, H3-170590 HFC-125 / 134a / 32, H3-370589 HFC-23 / 143a / 152a, H3-170588 HFC-125 / 143a / 134a, flat 3-170585, HFC-32 / 125 / 134a, flat 3-170584, HFC-23 / 134a / 152a, flat 3-170583, HFC-125 / 143a / 32, flat 4-222893 HFC-32 / 125, flat 4-154887, HFC-134 / 152a, flat 5-117645, HFC-23 / 134a / propane, flat 5-117643, HFC-125 / 134a / propane, flat 6-65561 HFC-23 / 152a / PFC-218, H6-32872, HFC-32 / PFC-218, H6-620433, HFC-32 / 125 / RC-318, H7-7373, HFC- 143a / 125 / 134a / heptane, pp. 8-176537, PFC-218 / RC-270 / HFC-152a, pp. 8-151569, propane / RC-270 / HFC-134a, pp. 8-127767, HFC- 32 / 134a / RC-318, flat 9-25480 is HFC-32 / 134a / 125 / isobutane, flat 9-59611 is HFC-134a / isobutane, flat 9-208941

HFC-32 / 152a / 125 / RC-270, Hei 9-221664 discloses a mixed refrigerant composition consisting of HFC-125 / 143a / 134a / RC-270.

And, Korean Patent Publication No. 91-9902 is HFC-23 / 32 / 152a, HFC-23 / 125 /

152a, HFC-32 / 143a / 152a, HFC-125 / 143a / 152a, HFC-32 / 125 / 125a, HFC-23 / 143a /

152a, Republic of Korea Patent Publication No. 91-9903 is HFC-23 / 32/134, HFC-23 / 32 / 134a, HFC-23 / 125/134, HFC-32 / 125/134, HFC-23 / 143a / 134a , HFC-125 / 143a / 134a, HFC-125 / 143a / 134, Korean Patent Publication No. 96-4485, HFC-32 / 23 / 134a, Korean Patent Publication No. 96-701168, HFC-227ea / HFC-152a , Korean Patent Publication No. 97-704853 discloses a mixed refrigerant composition consisting of HFC-134a / HCFC-124 / butane.

While many azeotropic or azeotropic mixed refrigerants are known in the art, there is a continuing need for azeotropic compositions having desirable end-use properties. However, as is well known in the art, in most cases the formation of azeotropic systems cannot be reliably predicted, making it difficult to deposit new azeotropic compositions.

On the other hand, in the development of CFC alternative refrigerants, HFC is most likely to be used as an alternative to CFC with an ODP of 0.0, but the problem of converting CFC to HFC is not easy. In other words, HFC refrigerants (R-134a, R-407C, R-410A) need to be supplemented with compressor systems and manufacturing facilities, including compressors, and are not suitable for mineral oil systems used as compressor lubricants in existing R12 systems. Therefore, refilling the mineral oil in the existing R12 system requires refilling after recharging the HFC refrigerant, and it is very cumbersome and time-consuming, especially when there is no oil outlet such as a car or a compact compressor. Therefore, research on the mixing technology of mixed refrigerants focuses mostly on HCFCs compatible with mineral oil.

In conclusion, the CFC alternative refrigerant should not be classified during boiling and should be a preferred azeotropic or azeotropic mixed composition. In addition, it is useful to mix HCFC which can be applied immediately without changing existing refrigeration system and manufacturing equipment and compatible with mineral oil. At the same time, it is natural to have excellent thermodynamic and physicochemical properties, low ODP and GWP (Global Warming Index), which is environmentally friendly, limited in toxicity and flammability.

The present invention to solve the above problems, Difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a'), trifluoroiodomethane (CF3I, It is to provide a new chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition composed hereinafter referred to as "13I1."

In order to achieve the above object, the chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition according to the present invention is difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32') Wt%, 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a') 40-45 wt%, trifluoroiodomethane (CF3I, hereinafter referred to as "13I1") Chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition composed of%.

Chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant compositions of the present invention refer to ternary liquid mixtures having substantially constant boiling points and behaving like a single material. One method of specifying an azeotropic composition is that a vapor produced by partial evaporation and distillation of a liquid has a composition that is substantially the same as the vapor from which it has been evaporated or distilled, ie a mixture distilled / refluxed without substantial compositional change. to be. A composition having a substantially constant boiling point, characterized by azeotropy, exhibits either a maximum or minimum boiling point when compared to the boiling point of an azeotropic mixture of the same component.

In the chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition of the present invention, as is well known to those skilled in the art, the composition of a given azeotrope at different pressures varies at least to some extent, and the change in pressure is also at least to some extent. Change the boiling point temperature. Therefore, a composition range rather than a fixed composition is often used to define an azeotrope composition.

For the chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant compositions of the present invention, certain weight percent relationships represent only one particular relationship and are recognized as being present for a given azeotrope that changes under the influence of pressure. Should be.

The chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition of the present invention can be specified by defining it as an azeotrope specified by a boiling point at a given pressure, thus unnecessarily limiting the scope of the present invention by a specific numerical composition. Unique features are given without limitation.

The chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant compositions of the present invention are characterized as azeotropic in that the mixtures within the following composition ranges exhibit substantially constant boiling points at atmospheric pressure. In order to have a substantially constant boiling point, the mixture is not very fractionated upon evaporation. After evaporation, there is only a small difference between the composition of the vapor and the composition of the initial liquid phase. This difference is such that the composition of the vapor and the liquid phase is considered to be substantially the same. Thus, any composition within this range exhibits the properties of a true ternary azeotropic composition.

Chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition according to the present invention is difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32') 40 ~ 47% by weight, 1,1,1,2 -Chlorodifluoromethane replacement consisting of 40 to 45% by weight of tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a') and 8 to 20% by weight of trifluoroiodomethane (CF3I, hereinafter referred to as "13I1") Ternary) relates to an azeotropic mixed refrigerant composition.

The vapor pressure at 25 ° C is 222-306 kPa and the boiling point is -23 ° C ± about 0.05 ° C. This composition is azeotropic because it exhibits a substantially constant vapor pressure, composition in the composition range.

The present invention is preferably 40% by weight of difluoromethane (CH2 F2: hereinafter referred to as 'HFC-32'), 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a') Wt%, trifluoroiodomethane (CF3I, hereinafter referred to as "13I1") The composition has a vapor pressure of 292.8 kPa, a COP efficiency of 2.23, azeotropy, limited flammability and almost no toxicity at 25 ° C. none.

Hereinafter, the present invention will be described in detail with reference to the following examples, which are not intended to limit the present invention.

Example 1

43 kg of difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 47 kg of 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a'), trifluoroiodomethane ( Chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition was prepared by mixing 10 kg CF3I, hereinafter referred to as "13I1".

Example 2

43 kg of difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 44 kg of 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a'), trifluoroiodomethane ( 13 kg of CF3I, hereinafter referred to as "13I1", were mixed to prepare a chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition.

Example 3

44 kg of difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 40 kg of 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a'), trifluoroiodomethane ( Chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition was prepared by mixing 16 kg CF3I, hereinafter referred to as "13I1".

Example 4

37 kg of difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 44 kg of 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a'), trifluoroiodomethane ( Chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition was prepared by mixing 19 kg of CF3I, hereinafter referred to as "13I1".

Example 5

40 kg of difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 44 kg of 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a'), trifluoroiodomethane ( Chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition was prepared by mixing 16 kg CF3I, hereinafter referred to as "13I1".

Experimental Example 1

43 wt% of difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 47 wt% of 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a'), trifluoro Chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition composed of 10% by weight of iodomethane (CF3I, hereinafter referred to as "13I1") was distilled in a distillation column, and the distillate composition was analyzed by gas chromatography. Specific gravity 7.682kg / ㎥ at 25 ℃, freezing capacity 371.11 kg / ㎥, vapor pressure (VAPOR PRESSURE) 292.8kPa, COP (efficiency) 2.23 at 25 ℃ is shown in Table 1 described below.

Experimental Example 2

43% by weight of difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 44% by weight of 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a'), trifluoro Chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition composed of 13% by weight of iodomethane (CF3I, hereinafter referred to as "13I1") was distilled in a distillation column and the distillate composition was analyzed by gas chromatography. Specific gravity 7.9 kg / ㎥ at 25 ℃, freezing capacity 368.85 kg / ㎥, vapor pressure (VAPOR PRESSURE) 222.8 kPa, COP (efficiency) 2.24 at 25 ℃, as shown in Table 1 described below.

Experimental Example 3

44% by weight of difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 40% by weight of 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a'), trifluoro Chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition composed of 16% by weight of iodomethane (CF3I, hereinafter referred to as "13I1") was distilled in a distillation column, and the distillate composition was analyzed by gas chromatography. Specific gravity 8.068kg / ㎥ at 25 ℃, freezing capacity 371.11 kg / ㎥, vapor pressure (VAPOR PRESSURE) 361.69 kPa, COP (efficiency) 2.246 at 25 ℃, it is shown in Table 1 described below.

Experimental Example 4

37% by weight of difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 44% by weight of 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a'), trifluoro Chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition composed of 19% by weight of iodomethane (CF3I, hereinafter referred to as "13I1") was distilled in a distillation column and the distillate composition was analyzed by gas chromatography. Specific gravity 8.4892 kg / ㎥ at 25 ℃, freezing capacity 382 kg / ㎥, vapor pressure (VAPOR PRESSURE) at 25 ℃ 305.6kPa, COP (efficiency) 2.22, as shown in Table 1 described below.

Experimental Example 5

40% by weight of difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 44% by weight of 1,1,1,2-tetrafluoroethane (CH2FCF3, hereinafter referred to as 'HFC-134a'), trifluoro Chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition composed of 16% by weight of iodomethane (CF3I, hereinafter referred to as "13I1") was distilled in a distillation column, and the distillate composition was analyzed by gas chromatography. Specific gravity 8.178kg / ㎥ at 25 ℃, freezing capacity 374.88 kg / ㎥, vapor pressure (VAPOR PRESSURE) 299.2 kPa, COP (efficiency) 2.23 at 25 ℃, it is shown in Table 1 described below.

TABLE 1

ITEM R-22 R-407C M410A Example 1 Example 2 Example 3 Example 4 Example 5 Creation costs R-134a: 50 R-32: 25 R-125: 25 32: 50 125: 50 R-134a: 43 R-32: 47 13I1: 10 R-134a: 43 R-32: 44 13 I1: 13 R-134a: 44 R-32: 40 13 I1: 16 R-134a: 37 R-32: 44 13I1: 19 R-134a: 40 R-32: 44 13I1: 16 Condenser temperature ℃ 54.4 54.4 54.4 54.4 54.4 54.4 54.4 54.4 Condenser pressure kPa 2,146 2375 3379.5 2,672 2650 2602 2738 2683 Liquid pressure kPa 2,146 2492 3383 2,793 2772 2727 2854 2813 Liquid vapor pressure kPa 2,146 2258 3376 2,551 2527 2477 2621 2573 Input temperature (steam) ℃ 54.4 56.51 54.45 56.36 56.39 56.48 56.25 56.33 Output temperature (Liquid) ℃ 54.4 52.26 54.35 52.42 52.36 52.28 52.52 52.44 Temperature range ℃ 0 4.25 0.1 3.94 4.03 4.2 3.73 3.89 Evaporator temperature ℃ -23.3 -23.3 -23.3 -23.3 -23.3 -23.3 -23.3 -23.3 Evaporator pressure kPa 215.6 222.8 353.15 258.9 258 253.3 271 264.1 Steam pressure kPa 215.6 253 352.7 292.8 222.8 289.2 305.6 299.2 Liquid pressure kPa 215.6 192.5 353.6 225.1 292.6 217.4 235.6 229 Input temperature (Liquid) ℃ -23.3 -26.48 -23.34 -26.45 -26.53 -26.71 -26.41 -26.51 Output temperature (steam) ℃ -23.3 -19.82 -23.26 -19.92 -19.75 -19.62 -19.89 -19.84 Evaporator Temperature Deviation ℃ 0 6.66 0.08 6.53 6.78 7.09 6.52 6.67 Pressure ratio - 9.95 10.66 9.57 10.32 10.27 10.27 10.1 10.2 Discharge temperature ℃ 152.0 132.7 147.4 152.6 150.9 148.6 152.3 151.6 importance kg / m ³ 7.563 7.696 10.55 7.682 7.9 8.068 8.489 8.178 Freezing capacity kg / m ³ 315.9 321.31 465.36 371.11 368.85 361.69 382 374.88 Latent heat of evaporation kcal / kg 41.78 41.75 44.11 48.31 46.69 44.83 45 45.84 C.O.P (efficiency) w / w 2.31 2.296 2.15 2.23 2.24 2.246 2.22 2.23 GWP 1500 1300.058 1300.1 825.01 823.116 827.326 782.347 802.95 ODP 0.04 0 0 0 0 0 0 0 M.W. g / mol 86.47 84.822 72.581 72.675 74.983 78.012 76.602 75.784

As described above, the present invention can obtain an azeotropic mixed refrigerant composition that is not classified under normal cooling or heating conditions, which simplifies the system and has no problem in repairing or modifying the system. In addition, it is possible to drop-in immediately because there is no need to change the design of the existing system, and it is commercially available in mineral oil, so it is not necessary to supplement the existing refrigerator production equipment.

Claims (1)

In the chlorodifluoromethane replacement (ternary) azeotropic mixed refrigerant composition, 3-chlorodifluoromethane replacement (three-way) azeotropic mixed refrigerant composition is 40 to 47% by weight of difluoromethane (CH2 F2, hereinafter referred to as 'HFC-32'), 1,1,1,2-tetrafluoro Chlorodifluoro, characterized in that 40 to 45% by weight of ethane (CH2FCF3, hereinafter referred to as 'HFC-134a') and 8 to 20% by weight of trifluoroiodomethane (CF3I, hereinafter referred to as "13I1") Methane replacement (ternary) azeotropic mixed refrigerant composition.