JPH0393888A - Working fluid - Google Patents

Abstract

PURPOSE:To obtain an incombustible working fluid, composed of perfluoropropylene, having a low solubility in polymer compounds without causing problems in destruction of ozonosphere and used for refrigerators, heat pumps, etc. CONSTITUTION:The objective working fluid obtained by adding, as necessary, about 0.01-5% compounds, such as epoxides, (thio) phosphites, phosphine sulfides, boron compounds, phenols, nitroalkanes and acrylic acid esters, as a stabilizer to perfluoroprophlene. Furthermore, compounds, such as fluorocarbons, pentafluorodimethyl ether or perfluoroethylamine, having the boiling point within + or -50 deg.C of that of the perfluoropropylene in an amount within the range of up to 50% based on the weight of the perfluoropropylene can be mixed therewith.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to working fluids used in refrigerators, heat pumps, etc.

BACKGROUND ART Conventionally, as working fluids or refrigerants, chlorofluorohydrocarbons, fluorohydrocarbons, azeotropic compositions thereof, and compositions in the vicinity thereof have been known. These are called fluorocarbons or fluorocarbon-based refrigerants, and trichlorofluoromethane (fluorocarbon-1) is currently used as a working fluid for refrigerators.
1), difluoromethane (Freon-12), etc. are mainly used. However, in recent years, it has been pointed out that certain types of fluorocarbons can destroy the ozone layer in the stratosphere when released into the atmosphere, resulting in serious adverse effects on the earth's ecosystem, including humans. Therefore, the use and production of fluorocarbons, which have a high possibility of depleting the ozone layer, has been restricted by international agreements. Types of fluorocarbons that are subject to restrictions include Freon-11 and Freon-12, which are commonly used as described above. frozen·
Restrictions on the use and production of fluorocarbons, the demand for which is increasing every year with the spread of air conditioning equipment, have a major impact on the current social structure as a whole, including the living environment. Therefore, there is an urgent need to develop new refrigerants that have no or low risk of causing ozone depletion problems.

Means for Solving the Problems The present inventor has conducted various studies in order to obtain a new refrigerant that has little or no effect on the ozone layer even when released into the atmosphere. As a result, it has been found that perfluorinated propylene meets the requirements for the purpose. We have also discovered that perfluorinated propylene has excellent properties as a working fluid for heat pumps.

That is, the present invention relates to a working fluid comprising perfluoropropylene.

The main physical properties of perfluorinated propylene used in the present invention are as follows.

Boiling point -27.0°C Critical temperature 92.4°C Critical pressure 3 5. 5kg/cJ・a
Molecular weight: 150 In the present invention, a stabilizer can be used in combination with barfluoropropylene, if necessary. That is, when a high degree of stability is required under harsh usage conditions, epoxides such as propylene oxide, 1,2 butylene oxide, glycidol; dimethyl phosphite, diisopropylphosphite, diphenyl phosphite, etc. phosphites; thiophosphites such as trilauryltrithiophosphite; phosphine sulfides such as triphenoxyphosphine sulfide and trimethylphosphine sulfide; boric acid, triethylborate, triphenylborate, phenylboronic acid, diphenylboronic acid, etc. boron compound; 2,6-di-t
Phenols such as ert-butyl para-cresol; Nitroalkanes such as nitromethane and nitroethane; Acrylic acid esters such as methyl acrylate and ethyl acrylate; Other dioxane, tert-butanol,
Pentaerythritol, barisopropenyltoluene:
A stabilizer such as 0.01 to 5% of the weight of the working fluid can be added.

It is also possible to mix perfluoropropylene with another compound having a boiling point within ±50° C. of the boiling point within a range of up to 50% of the weight of perfluoropropylene. Such compounds include Freon-22.32,124,
125, 134a, 142b, 143a. Examples include fluorocarbons such as 152a; ethers such as pentafluorodi-methyl ether; and amines such as perfluoroethylamine.

Effects of the Invention The perfluoropropylene used in the present invention is relatively easily decomposed and does not contain chlorine atoms and bromine atoms that affect the ozone layer, so there is no risk of causing the problem of ozone layer destruction.

Further, since perfluoropropylene has low solubility in high molecular compounds, it can be used as is without changing the material in existing refrigeration equipment or the like.

Furthermore, since perfluorinated propylene is nonflammable, it can be used as is in ordinary refrigeration equipment.

Furthermore, the perfluoropropylene of the present invention is useful not only as a refrigerant but also as a working fluid for heat pumps and the like.

EXAMPLES Examples will be shown below to further clarify the features of the present invention.

Example 1 In a 1-horsepower refrigerator that uses perfluoropropylene as a refrigerant, (I) condensation temperature [°C] and (II) evaporation temperature [°C] of the refrigerant in the condenser are set to the values shown in Table 1. The operation was carried out with the degree of supercooling of the condenser set to 0°C.

Table 1 shows (m) evaporation pressure [kg/cJ] under each condition.
], (IV) Condensation pressure [kg/allY], (V
) Refrigeration capacity [kcal/m3] and (VI) discharge gas temperature are shown.

Comparative Example 1 A refrigerator was operated in the same manner as in Example 1 except that Freon-11 was used instead of perfluoropropylene. The results are also shown in Table 1.

Example 2 Same as Example 1 except for changing some operating conditions,
Operated the refrigerator. The results are shown in Table 2.

Comparative Example 2 A refrigerator was operated in the same manner as in Example 2 except that Freon-11 was used instead of perfluorinated propylene. The results are also shown in Table 2.

From the results shown in Tables 1 and 2, it is clear that the working fluid according to the present invention exhibits superior refrigerating ability compared to conventional working fluids.

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Claims (1)

[Claims] (1) Working fluid consisting of perfluoropropylene.