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US-12617990-B2 - Refrigerant compositions

US12617990B2US 12617990 B2US12617990 B2US 12617990B2US-12617990-B2

Abstract

A composition comprising trifluoroiodomethane (CF 3 I) and 1,1-difluoroethylene (R-1132a) is described. The composition can also comprise additional compounds, such as at least one non-flammable compound selected from the group consisting of carbon dioxide (CO2; R-744), tetrafluoromethane (R-14), trifluoromethane (R-23) and perfluoroethane (R-116) or at least one additional compound of lower volatility than 1,1-difluoroethylene selected from the group consisting of 1,1,2-trifluoroethylene (R-1123), difluoromethane (R-32), propane (R-290), propylene (R-1270), fluoroethane (R-161), pentafluoroethane (R-125), 1,1,1,2-tetrafluoroethane (R-134a), 2,3,3,3-tetrafluopropene (R-1234yf), isobutane (R-600a), n-butane (R-600), trans-1,3,3,3-tetrafluopropene (R-1234ze(E)), 3,3,3-trifluoropropene (R-1243zf), 1,2,3,3,3-pentafluoropropene (R-1225ye), 1, 1,1,2,3,3,3-heptafluoropropane (R-227ea), 1,1-difluoroethane (R-152a), cis-1,3,3,3-tetrafluopropene (R-1234ze(Z)), 1-chloro-3,3,3-trifluoropropene (R-1233zd(E/Z)) and 1,1,1,4,4,4-hexafluoro-2-butene (R-1336mzz(E/Z)). The compositions have utility as refrigerants in vapour compression heat transfer systems.

Inventors

  • Robert Low

Assignees

  • MEXICHEM FLUOR S.A. DE C.V.

Dates

Publication Date
20260505
Application Date
20191112
Priority Date
20181112

Claims (20)

  1. 1 . A ternary or higher refrigerant composition comprising from 26 to 86 weight % trifluoroiodomethane (CF 3 I), 4 to 10 weight % 1,1-difluoroethylene (R-1132a), and 10 to 70 weight % 2,3,3,3-tetrafluoropropene (R-1234yf), based on the total weight of the composition.
  2. 2 . The composition of claim 1 which comprises from 26 to 50 weight % of CF 3 I.
  3. 3 . The composition of claim 1 wherein the CF 3 I is present in an amount of from 26 to 70 weight % based on the total weight of the composition.
  4. 4 . The composition of claim 1 wherein the composition comprises: from 26 to about 50 weight % CF 3 I and from 10 to about 40 weight % R-1234yf.
  5. 5 . The composition according to claim 1 , wherein the composition comprises from 28 to 82 weight % of CF 3 I, from 4 to 10 weight % of R-1132a and from 10 to 60 weight % of R-1234yf based on the total weight of the composition.
  6. 6 . The composition of claim 1 wherein the composition further comprises carbon dioxide (CO 2 ; R-744).
  7. 7 . The composition of claim 6 wherein the CO 2 is present in an amount of from about 1 to about 40 weight % based on the total weight of the composition.
  8. 8 . The composition of claim 6 wherein the CO 2 is present in an amount of from about 1 to about 30 weight % based on the total weight of the composition.
  9. 9 . The composition of claim 6 wherein the CO 2 is present in an amount of from about 1 to about 20 weight % based on the total weight of the composition.
  10. 10 . The composition of claim 6 wherein the CO 2 is present in an amount of from about 1 to about 10 weight % based on the total weight of the composition.
  11. 11 . The composition according to claim 1 , wherein the composition further comprises R-32.
  12. 12 . The composition according to claim 1 comprising from 28 to 82 weight % of CF 3 I, from 4 to 10 weight % of R-1132a, from 5 to 12 weight % of R-32 and from 10 to 60 weight % of R-1234yf based on the total weight of the composition.
  13. 13 . The composition of claim 1 further comprising a stabilizer, wherein the stabilizer is selected from the group consisting of diene-based compounds, phosphates, phenol compounds and epoxides, and mixtures thereof.
  14. 14 . The composition of claim 1 which is non-flammable or only weakly flammable as determined by the test method of ASHRAE Standard 34:2016.
  15. 15 . A composition of claim 1 consisting essentially of the stated components.
  16. 16 . A composition of claim 1 , wherein the refrigerant composition has: a. a higher flammable limit; b. a higher ignition energy; and/or c. a lower flame velocity compared to R-1132a alone.
  17. 17 . A composition of claim 1 , wherein the refrigerant composition is non-flammable at ambient temperature, or wherein the composition is non-flammable at 60° C.
  18. 18 . The composition of claim 1 which has a Global Warming Potential (GWP) below 150.
  19. 19 . The composition of claim 1 wherein the refrigerant composition has a temperature glide in an evaporator or condenser of less than about 10K.
  20. 20 . A method of heat transfer comprising providing a composition as claimed in claim 1 as a refrigerant in a vapour compression heat transfer system.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is the U.S. National Stage application of PCT International application no. PCT/GB2019/053202, filed on Nov. 12, 2019, titled COMPOSITIONS, designating the United States, which claims priority to Great Britain application no. 1911609.4, filed on Aug. 14, 2019, to Great Britain application no. 1901889.4, filed Feb. 11, 2019, and to Great Britain application no. 1818411.9, filed on Nov. 12, 2018, the contents of each are which incorporated herein by reference in their entirety. The present invention relates to compositions and more particularly to refrigerant compositions comprising 1,1-difluoroethylene (R-1132a; vinylidene fluoride) and trifluoroiodomethane (CF3I) that are useful as working fluids in vapour compression cycles for refrigeration, air-conditioning and heat pump applications. The use of trifluoroiodomethane (CF3I) as a refrigerant has been proposed. The attraction of CF3I as a refrigerant component is that it can chemically suppress the flammability of flammable refrigerants with which it is blended. Blends comprising flammable refrigerants, such as R-1234yf (2,3,3,3-tetrafluopropene) with non-flammable refrigerants, such as R-134a (1,1,1,2-tetrafluoroethane), already exist. However, in the absence of any chemical flame suppression effect, the flammability can only be mitigated by physical dilution with the non-flammable refrigerant. This means that even a weakly flammable refrigerant like R-1234yf must be mixed in almost 50/50 proportions with non-flammable R-134a. Furthermore, as non-flammable fluorinated refrigerants like R-134a and R-125 tend to have high Global Warming Potentials (GWP), a non-flammable mixture comprising at least one flammable, low GWP refrigerant like R-1234yf and a non-flammable, fluorinated refrigerant will still have a relatively high GWP compared to that of the flammable refrigerant alone. Regulations restricting the quantity of high-GWP refrigerants that can be used already exist in Europe and are pending in the Kigali Amendment to the Montreal Protocol. As a result, it is desirable to find mixtures and preferably non-flammable mixtures with lower GWPs than are currently available. Trifluoroiodomethane has a very low effective GWP and so is potentially of interest in suppressing the flammability of any flammable refrigerants with which it is mixed in binary, ternary and higher refrigerant mixtures. 1,1-difluoroethylene is a high capacity, flammable refrigerant with a boiling point of −83° C. It is classified by ASHRAE in flammability class 2 by the ASHRAE Standard 34:2016 test method. Non-flammable refrigerants have traditionally been considered the most desirable and versatile class of refrigerant, but the growing desire for refrigerants having very low GWPs means that there is increasing acceptance of refrigerants which are flammable, but whose flammability is reduced compared to highly flammable refrigerants like propane, or even compared to moderately flammable refrigerants. In particular, the use of refrigerants classed as “weakly flammable” (2L) by ASHRAE Standard 34:2016 is now being considered by the industry. Several manufacturers already offer equipment for refrigeration, air-conditioning and heat pump applications using 2L flammability class refrigerants. 2L refrigerants are distinguished from other moderately flammable refrigerants by exhibiting a low burning velocity of less than 10 cm/s. There is a need for a non-flammable or weakly flammable refrigerant composition with a low GWP that can operate efficiently in vapour compression cycles for refrigeration, air-conditioning and heat pump applications. In particular, there is a need for a non-flammable or weakly flammable refrigerant composition that exploits the beneficial properties of 1,1-difluoroethylene (R-1132a) and, in particular, its high refrigeration capacity. We have found that compositions comprising 1,1-difluoroethylene (R-1132a; vinylidene fluoride) and trifluoroiodomethane (CF3I) and preferably at least one further refrigerant compound are useful as working fluids in vapour compression cycles for refrigeration, air-conditioning and heat pump applications. Furthermore, the non-flammable trifluoroiodomethane can in preferred embodiments effectively supress the flammability of flammable refrigerants including 1,1-difluoroethylene contained in the compositions to result in refrigerant compositions that are either weakly flammable (flammability class 2L) and preferably non-flammable as determined in accordance with the test method of ASHRAE Standard 34:2016. The compositions may also be used as solvents, foam blowing agents, propellants, degreasing agents, and as working fluids in Organic Rankine Cycle equipment for generation of mechanical or electrical power. Accordingly, one aspect of the present invention provides a composition, especially a refrigerant composition, comprising 1,1-difluoroethylene (R-1132a) and trifluoroiodomethane (CF3