IE904049A1 - An azeotropic mixture with a low boiling point based on fluoroalkanes - Google Patents

An azeotropic mixture with a low boiling point based on fluoroalkanes

Info

Publication number
IE904049A1
IE904049A1 IE404990A IE404990A IE904049A1 IE 904049 A1 IE904049 A1 IE 904049A1 IE 404990 A IE404990 A IE 404990A IE 404990 A IE404990 A IE 404990A IE 904049 A1 IE904049 A1 IE 904049A1
Authority
IE
Ireland
Prior art keywords
azeotrope
boiling point
employed
perfluoropropane
low boiling
Prior art date
Application number
IE404990A
Other versions
IE64735B1 (en
Inventor
Didier Arnaud
Jean-Claude Tanguy
Daniel Sallet
Original Assignee
Atochem
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from FR8914788A external-priority patent/FR2654427B1/en
Application filed by Atochem filed Critical Atochem
Publication of IE904049A1 publication Critical patent/IE904049A1/en
Publication of IE64735B1 publication Critical patent/IE64735B1/en

Links

Classifications

    • AHUMAN NECESSITIES
    • A62LIFE-SAVING; FIRE-FIGHTING
    • A62DCHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
    • A62D1/00Fire-extinguishing compositions; Use of chemical substances in extinguishing fires
    • A62D1/0028Liquid extinguishing substances
    • A62D1/0057Polyhaloalkanes
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C19/00Acyclic saturated compounds containing halogen atoms
    • C07C19/08Acyclic saturated compounds containing halogen atoms containing fluorine
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08JWORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/04Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
    • C08J9/12Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent
    • C08J9/14Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent organic
    • C08J9/143Halogen containing compounds
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K3/00Materials not provided for elsewhere
    • C09K3/30Materials not provided for elsewhere for aerosols
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K5/00Heat-transfer, heat-exchange or heat-storage materials, e.g. refrigerants; Materials for the production of heat or cold by chemical reactions other than by combustion
    • C09K5/02Materials undergoing a change of physical state when used
    • C09K5/04Materials undergoing a change of physical state when used the change of state being from liquid to vapour or vice versa
    • C09K5/041Materials undergoing a change of physical state when used the change of state being from liquid to vapour or vice versa for compression-type refrigeration systems
    • C09K5/044Materials undergoing a change of physical state when used the change of state being from liquid to vapour or vice versa for compression-type refrigeration systems comprising halogenated compounds
    • C09K5/045Materials undergoing a change of physical state when used the change of state being from liquid to vapour or vice versa for compression-type refrigeration systems comprising halogenated compounds containing only fluorine as halogen
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08JWORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2207/00Foams characterised by their intended use
    • C08J2207/04Aerosol, e.g. polyurethane foam spray
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K2205/00Aspects relating to compounds used in compression type refrigeration systems
    • C09K2205/10Components
    • C09K2205/12Hydrocarbons
    • C09K2205/128Perfluorinated hydrocarbons
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K2205/00Aspects relating to compounds used in compression type refrigeration systems
    • C09K2205/32The mixture being azeotropic

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Dispersion Chemistry (AREA)
  • Combustion & Propulsion (AREA)
  • Medicinal Chemistry (AREA)
  • Emergency Management (AREA)
  • Physics & Mathematics (AREA)
  • General Chemical & Material Sciences (AREA)
  • Thermal Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Business, Economics & Management (AREA)
  • Polymers & Plastics (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Fire-Extinguishing Compositions (AREA)
  • Nitrogen Condensed Heterocyclic Rings (AREA)
  • Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Detergent Compositions (AREA)
  • Medicinal Preparation (AREA)

Abstract

An azeotrope of minimum boiling point, capable of being employed as refrigerating fluid replacing chlorofluorocarbons or as an extinguishing agent replacing bromofluorocarbons and chlorobromofluorocarbons. The azeotrope according to the invention is a mixture of 1,1,1,2-tetrafluoroethane and perfluoropropane. At normal boiling point (approximately -41.1 DEG C at 1.013 bar) its perfluoropropane content is approximately 76 mass% and that of 1,1,1,2-tetrafluoroethane is 24 %. This azeotrope can also be employed as an aerosol propellant or as a blowing agent for plastic foams.

Description

The present invention relates to a mixture of fluoroalkanes with a low boiling point, which has little or no effect on the environment and is capable of being employed to replace chlorofluorocarbons (CFCs) in low5 temperature compression refrigeration systems and to replace trifluorobromomethane and difluorochlorobromomethane as extinguishing agent.
It is now established that because of their effect on ozone, CFCs will have, in the longer or shorter term, to be replaced with refrigerating fluids containing less chlorine which are, consequently, less aggressive towards the environment. Bearing in mind its very small effect on the environment, 1,1,1,2-tetrafluoroethane (R 134a) has already been proposed as a substitute for CFCs. However, because of its high boiling point (-26.5°C), the use of R 134a by itself is restricted to intermediate evaporation temperature applications (-25°C; -26°C) and cannot be used in low boiling temperature applications (for example -40°C). In fact, the minimum temperature reached in the evaporator is in practice limited by the normal boiling temperature of the refrigerating fluid in order to avoid the entry of air or brine into the plant in case of leakages at the evaporator, as this would present the risk of disturbing the normal operation of the system.
In the field of extinguishing and of firefighting, - 3 use is made principally of chlorobromofluoroalkanes and bromofluoroalkanes, particularly trifluorobromomethane, difluorochlorobromomethane and 1,1,2,2-tetrafluoro-1,2dibromoethane. These compounds are employed especially in premises where corrosion-sensitive electrical and electronic equipment is to be found (e.g. data processing rooms, telephone exchanges, engine rooms aboard ships). However, like the CFCs, these compounds have high ODPs (ozone depletion potentials).
It has now been found that 1,1,1,2tetrafluoroethane (R 134a) and perfluoropropane (R 218) form an azeotrope with a minimum boiling point of approximately -41.1°C at 1.013 bars and whose R 218 content at the normal boiling point is approximately 76 % on a mass basis. This composition naturally varies as a function of the pressure of the mixture and, at a given pressure, can be easily determined by well-known methods. Accordingly the present invention provides a minimum boiling point azeotrope which is a mixture of 1,1,1,2-tetrafluoroethane and perfluoropropane such that at its normal boiling point it contains approximately 76 % on a mass basis of perfluoropropane and 24 % on a mass basis of 1,1,1,2tetrafluoroethane.
The azeotrope according to the invention has the advantage of exhibiting substantially zero ODP. This means that it is devoid of destructive action on the - 4 stratospheric ozone layer. The ODP is defined as the ratio between the lowering of the ozone column recorded during the emission of a unit mass of substance and the same lowering in the case of trichlorofluoromethane, chosen as reference (ODP = 1). By way of indication, trifluorobromomethane has an ODP of 10.
Because of its low boiling point, the azeotropic mixture according to the invention can be employed as a refrigerating fluid in applications at low boiling temperatures (-40°C; -41°C), as in the case of low temperature commercial refrigeration where R 218 by itself has mediocre thermodynamic properties and where R 134a by itself cannot be employed for the reasons set out above.
It has also been found that this azeotrope can be employed as an extinguishing agent, especially to replace trifluorobromomethane and difluorochlorobromomethane. In fact, it has a Cup Burner value lower than 10 % and consequently exhibits a high extinguishing power.
The azeotrope according to the invention can be employed for firefighting according to the same techniques as trifluorobromomethane and difluorochlorobromomethane. Thus, it can be advantaqeously employed for the protection of premises using the so-called complete immersion technique. It can be pressurized with inert gases such as nitrogen, and this allows its discharge speed to be increased. It can also be employed in portable extinguisher 1E 904049 - 5 techniques.
Given its physical properties which are close to those of the CFCs, the mixture according to the invention can also be employed as an aerosol propellant or as a blowing agent for plastic foams.
The following Examples further illustrate the present invention.
EXAMPLE 1 The azeotrope according to the invention was 10 investigated experimentally at various temperatures by analysis of the liquid phase and vapour phase compositions, using gas phase chromatography, for various mixtures of R 134a and R 218.
The pressures were measured with an accuracy 15 greater than 0.02 bar by means of a Heise manometer. The temperatures were measured to within 0.02°C by means of a 1,000-ohm platinum probe.
Graph 1 of the accompanying Figure shows the liquid/vapour equilibrium curve for R 218/R 134a mixtures, established at a temperature of 20.3°C. On this graph the abscissa shows the mass fraction of R 218 and the ordinate the absolute pressure in bars; the - signs correspond to the experimental points.
A curve similar to that of Graph 1 can be obtained for each temperature. On successively adding R 218 to R 134a the pressure developed by the mixture increases - 6 steadily, then passes through a maximum and decreases steadily, which demonstrates the existence of the azeotrope with a minimum boiling point.
Table 1, which follows, gives the pressure5 temperature relationship for this azeotrope, compared with that for the pure substances.
TABLE 1 Temperature (°C) Absolute pressure (bars) R 218/R 134a azeotrope Pure R 134a Pure R 218 -40.0 0.3 20.3 39.9 1.10 4.92 9.08 15.10 0.53 2.94 5.78 10.26 0.87 4.20 7.66 12.98 The vapour pressure of the azeotrope remains higher 20 than the vapour pressure of the pure substances over a wide range of temperature. These data show that the mixture remains azeotropic throughout this temperature range.
EXAMPLE 2 The characterization of the azeotrope at the normal 25 boiling point was carried out by direct measurement of the boiling temperature of various R 218/R 134a mixtures by means of an ebulliometer.
Table 2 summarizes the results obtained and enables the azeotrope to be characterized by: - its normal boiling point which is equal to approximately -41.1°C, - its mass content of R 218, which is equal to approximately 76 %.
TABLE 2 Temperature (°C) Mass content of R 218 -26.5 0 -40.4 70.9 -40.8 74.6 -41.0 75.2 -41.0 76.4 -40.9 78.3 -36.7 100.0 EXAMPLE 3 This Example illustrates the use of the azeotrope according to the invention as a refrigerating fluid.
The thermodynamic performance of the azeotropic 25 mixture according to the invention was compared with the - 8 performance of the two constituents by themselves, under conditions close to those encountered in commercial refrigeration systems, namely the following: - condensation temperature : +30°C - evaporation temperature : -30°C - liquid supercooling : - 5®C - vapour superheating at the compressor : +15°C Table 3 summarizes the thermodynamic performance 10 observed under these conditions for pure R 134a, pure R 218 and the azeotropic mixture according to the invention.
TABLE 3 R 218/R 134a azeotrope Pure R 218 Pure R 134a Evaporation pressure (bars) 1.69 1.36 0.85 Condensation pressure (bars) 11.58 10.1 7.70 Compression ratio 6.85 7.43 9.06 20 Refrigerating capacity (kJ/m3) 877 710 640 Coefficient of performance 2.7 2.4 3.1 It can be seen that the azeotropic mixture according to the invention offers a number of advantages over pure R 134a or R 218, especially: - 9 - a lower compression ratio and therefore an improvement in the volumetric efficiency of the compressor and consequently lower plant running costs - a considerably higher available volumetric refrigerating capacity which, in practice, for a given refrigerating capacity, makes it possible to employ a smaller compressor than that required for pure R 134a or R 218.
In the case of the azeotrope according to the 10 invention, this increase in available volumetric refrigerating capacity also makes it possible to increase by 37 % the available refrigerating capacity of an existing plant using R 134a.
EXAMPLE 4 This Example illustrates the use of the azeotrope according to the invention as an extinguishing agent.
The extinguishing efficiency is generally measured by the so-called Cup Burner method.
This method, described in draft standard 20 ISO/DIS 7075-1, shows the minimum percentage of extinguishing compound (measured by volume) in a mixture of air plus extinguishing compound needed to extinguish a flaming liquid fuel.
The lower the Cup Burner value, the more effective 25 is the extinguishing compound.
We employed ethanol as the liquid fuel. 9.5 %. - 10 The Cup Burner value for the R 218/R 134a azeotropic mixture according to the invention is equal to

Claims (7)

1. A minimum boiling point azeotrope which is a mixture of 1,l,l,2-tetrafluoroethane and perfluoropropane such that at its normal boiling point it contains 5 approximately 76 % on a mass basis of perfluoropropane and 24 % on a mass basis of 1,1,1,2-tetrafluoroethane.
2. Use of the azeotrope according to Claim 1 as a refrigerating fluid.
3. Use of the azeotrope according to Claim 1 as 10 an aerosol propellant.
4. Use of the azeotrope according to Claim 1 as a blowing agent for plastic foams.
5. Use of the azeotrope according to Claim 1 as an extinguishing agent.
6. A minimum boiling point azeotrope according to Claim 1, substantially as hereinbefore described and exemplified.
7. Use according to any one of Claims 2-5, substantially as hereinbefore described and exemplified.
IE404990A 1989-11-10 1990-11-09 An azeotropic mixture with a low boiling point based on fluoroalkanes IE64735B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8914788A FR2654427B1 (en) 1989-11-10 1989-11-10 NEW AZEOTROPIC MIXTURE WITH LOW BOILING POINT BASED ON FLUOROALKANES AND ITS APPLICATIONS.
FR909007153A FR2662944B2 (en) 1989-11-10 1990-06-08 NEW AZEOTROPIC MIXTURE WITH LOW BOILING POINT BASED ON FLUOROALKANES AND ITS APPLICATIONS.

Publications (2)

Publication Number Publication Date
IE904049A1 true IE904049A1 (en) 1991-05-22
IE64735B1 IE64735B1 (en) 1995-09-06

Family

ID=26227656

Family Applications (1)

Application Number Title Priority Date Filing Date
IE404990A IE64735B1 (en) 1989-11-10 1990-11-09 An azeotropic mixture with a low boiling point based on fluoroalkanes

Country Status (14)

Country Link
EP (1) EP0427604B1 (en)
JP (1) JPH0729956B2 (en)
KR (1) KR920009972B1 (en)
AT (1) ATE88452T1 (en)
AU (1) AU633648B2 (en)
CA (1) CA2028735A1 (en)
DE (1) DE69001423T2 (en)
DK (1) DK0427604T3 (en)
ES (1) ES2069717T3 (en)
FI (1) FI97053C (en)
FR (1) FR2662944B2 (en)
IE (1) IE64735B1 (en)
NO (1) NO173230C (en)
PT (1) PT95848B (en)

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU629975B2 (en) * 1989-08-21 1992-10-15 Great Lakes Chemical Corporation Fire extinguishing methods and blends utilizing hydrofluorocarbons
FR2682395B1 (en) * 1991-10-09 1993-12-10 Atochem MIXTURES OF 1,1,1-TRIFLUOROETHANE, PERFLUOROPROPANE AND PROPANE, AND THEIR APPLICATIONS AS REFRIGERANTS, AS AEROSOL PROPELLANTS OR AS PLASTIC FOAM EXPANDING AGENTS.
US5236611A (en) * 1991-10-28 1993-08-17 E. I. Du Pont De Nemours And Company Mixtures of perfluoropropane and trifluoroethane
WO1993011201A1 (en) * 1991-12-03 1993-06-10 United States Environmental Protection Agency Refrigerant compositions and processes for using same
FR2686092B1 (en) * 1992-01-13 1994-09-16 Atochem Elf Sa MIXTURES OF 1,1,1-TRIFLUOROETHANE AND PERFLUOROPROPANE AND THEIR APPLICATIONS AS REFRIGERANTS, AS AEROSOL PROPELLERS OR AS PLASTIC FOAM EXPANSION AGENTS.
EP0556722A1 (en) * 1992-02-19 1993-08-25 Hoechst Aktiengesellschaft Method of decreasing the total pressure in aerosol containers
US5248433A (en) * 1992-04-30 1993-09-28 E. I. Du Pont De Nemours And Company Binary azeotropic mixtures of octafluoropropane and fluoroethane
US5494601A (en) * 1993-04-01 1996-02-27 Minnesota Mining And Manufacturing Company Azeotropic compositions
US5401429A (en) * 1993-04-01 1995-03-28 Minnesota Mining And Manufacturing Company Azeotropic compositions containing perfluorinated cycloaminoether
GB9522701D0 (en) * 1995-11-07 1996-01-10 Star Refrigeration Centrifugal compression refrigerant composition
DK0998539T3 (en) 1997-07-15 2002-10-28 Rhodia Ltd refrigerant compositions
US7258813B2 (en) 1999-07-12 2007-08-21 E.I. Du Pont De Nemours And Company Refrigerant composition
DE10121544B4 (en) * 2001-05-03 2007-08-16 Axima Refrigeration Gmbh Process for the liquefaction of a reactive gas
GB0223724D0 (en) 2002-10-11 2002-11-20 Rhodia Organique Fine Ltd Refrigerant compositions
CA2507639C (en) 2002-11-29 2013-08-06 Rhodia Organique Fine Limited Chiller refrigerants

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3607755A (en) * 1968-11-25 1971-09-21 Allied Chem Novel halocarbon compositions
US4101467A (en) * 1976-02-27 1978-07-18 The Dow Chemical Company Soft ethylenic polymer foams
US4810403A (en) * 1987-06-09 1989-03-07 E. I. Du Pont De Nemours And Company Halocarbon blends for refrigerant use
US4944890A (en) * 1989-05-23 1990-07-31 E. I. Du Pont De Nemours And Company Compositions and process of using in refrigeration

Also Published As

Publication number Publication date
EP0427604B1 (en) 1993-04-21
DE69001423D1 (en) 1993-05-27
NO173230B (en) 1993-08-09
PT95848A (en) 1991-09-13
NO904726D0 (en) 1990-10-31
FI905565A0 (en) 1990-11-09
FI97053B (en) 1996-06-28
PT95848B (en) 1997-11-28
KR920009972B1 (en) 1992-11-09
KR910009620A (en) 1991-06-28
NO904726L (en) 1991-05-13
CA2028735A1 (en) 1991-05-11
EP0427604A1 (en) 1991-05-15
AU6654990A (en) 1991-05-16
DK0427604T3 (en) 1993-05-17
FI97053C (en) 1996-10-10
JPH03173839A (en) 1991-07-29
AU633648B2 (en) 1993-02-04
ATE88452T1 (en) 1993-05-15
IE64735B1 (en) 1995-09-06
FR2662944A2 (en) 1991-12-13
FR2662944B2 (en) 1992-09-04
NO173230C (en) 1993-11-17
DE69001423T2 (en) 1993-09-09
JPH0729956B2 (en) 1995-04-05
ES2069717T3 (en) 1995-05-16

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