Use of alkyl perfluoroalkene ethers and mixtures thereof in high temperature heat pumps
Disclosed herein is a method for producing heating in a high temperature heat pump having a heat exchanger. The method comprises extracting heat from a working fluid, thereby producing a cooled working fluid wherein said working fluid comprises at least one alkyl perfluoroalkene ether. Also disclosed is a method of raising the maximum feasible condenser operating temperature in a high temperature heat pump apparatus. The method comprises charging the high temperature heat pump with a working fluid comprising at least one alkyl perfluoroalkene ether. Also disclosed is a high temperature heat pump apparatus. The apparatus contains a working fluid comprising at least one alkyl perfluoroalkene ether. Also disclosed is a composition comprising at least one alkyl perfluoroalkene ether, and specialized additives or lubricants for use in a high temperature heat pump.
1. A method for producing heating in a high temperature heat pump having a heat exchanger comprising extracting heat from a working fluid, thereby producing a cooled working fluid wherein said working fluid comprises at least one alkyl perfluoroalkene ether, wherein the heat exchanger operates at a temperature greater than about 150° C.
2. The method of claim 1 wherein the heat exchanger is selected from the group consisting of a supercritical working fluid cooler and a condenser.
3. The method of claim 1 further comprising passing a first heat transfer medium through the heat exchanger, whereby said extraction of heat heats the first heat transfer medium, and passing the heated first heat transfer medium from the heat exchanger to a body to be heated.
4. The method of claim 3 , wherein the first heat transfer medium is an industrial heat transfer liquid and the body to be heated is a chemical process stream.
5. The method of claim 3 , further comprising compressing the working fluid vapor in a dynamic or a positive displacement compressor.
6. The method of claim 5 , wherein the dynamic compressor is a centrifugal compressor.
7. The method of claim 1 further comprising expanding the working fluid and then heating the working fluid in a second heat exchanger to produce a heated working fluid.
8. The method of claim 7 wherein said second heat exchanger is an evaporator and the heated working fluid is a vapor.
9. The method of claim 1 further comprising passing a fluid to be heated through said condenser, thus heating the fluid.
10. The method of claim 1 , wherein said working fluid comprises at least one alkyl perfluoroalkene ether selected from the group consisting of:
a) compounds of formula CF 3 (CF 2 ) x CF═CFCF(OR)(CF 2 ) y CF 3 , CF 3 (CF 2 ) x C(OR)═CFCF 2 (CF 2 ) y CF 3 , CF 3 CF═CFCF(OR)(CF 2 ) x (CF 2 ) y CF 3 , CF 3 (CF 2 ) x CF═C(OR)CF 2 (CF 2 ) y CF 3 , or mixtures thereof, wherein R can be either CH 3 , C 2 H 5 or mixtures thereof, wherein x and y are independently 0, 1, 2 or 3, and wherein x+y=0, 1, 2, or 3;
b) compounds of formulas CF 3 (CF 2 ) x CF═CFCF(OR)(CF 2 ) y CF 3 , CF 3 (CF 2 ) x C(OR)═CFCF 2 (CF 2 ) y CF 3 , CF 3 CF═CFCF(OR)(CF 2 ) x (CF 2 ) y CF 3 , CF 3 (CF 2 ) x CF═C(OR)CF 2 (CF 2 ) y CF 3 , and mixtures thereof; wherein x and y are independently 0, 1, 2, 3, or 4 and wherein x+y=0, 1, 2, 3, or 4; and wherein R is 2,2,3,3-tetrafluoro-1-propyl, 2,2,3,3,3-pentafluoro-1-propyl, 2,2,2-trifluoro-1-ethyl, 2,2,3,3,4,4,5,5-octafluoro-1-pentyl, or 1,1,1,3,3,3-hexafluoro-2-propyl; and
c) mixtures of compounds from (a) and (b).
11. The method of claim 10 , wherein the working fluid further comprises at least one compound selected from a hydrofluorocarbon, a hydrochlorocarbon, a hydrofluoroether, a hydrofluoroolefin, a hydrochlorofluorolefin, a siloxane, a hydrocarbon, an alcohol, and a perfluoropolyether, or mixtures thereof.
12. The method or of claim 11 , wherein the working fluid comprises an azeotropic or near-azeotropic mixture.
13. The method of claim 12 , wherein the azeotropic or near azeotropic mixture comprises at least one methyl perfluoroheptene ether and at least one compound selected from the group consisting of heptane, ethanol, and trans-1,2-dichloroethene.
14. The method of claim 12 , wherein the azeotropic or near azeotropic mixture comprises at least one methyl perfluoropentene ether and at least one compound selected from the group consisting of trans-1,2-dichloroethene, methanol, ethanol, 2-propanol, heptane, hexane, cyclopentane, ethyl formate, methyl formate, C 4 F 9 OCH 3 , C 4 F 9 OC 2 H 5 , HFC-365mfc, and 1-bromopropane.
15. The method of claim 1 , wherein the working fluid comprises at least one alkyl perfluoroalkene ether selected from the group consisting of cis-2-methoxyperfluoro-2-octene, trans-2-methoxyperfluoro-2-octene, and 2-methoxyperfluoro-3-octene, or a mixture thereof.
16. The method of claim 1 , wherein the working fluid comprises at least one alkyl perfluoroalkene ether selected from the group consisting of 5-methoxyperfluoro-3-heptene, 3-methoxyperfluoro-3-heptene, 4-methoxyperfluoro-2-heptene, and 3-methoxyperfluoro-2-heptene, or mixtures thereof.
17. The method of claim 1 , wherein the working fluid comprises at least one alkyl perfluoroalkene ether selected from the group consisting of 4 methoxyperfluoro-2-pentene, 2-methoxyperfluoro-2-pentene, 3-methoxyperfluoro-2-pentene, and 2-methoxyperfluoro-3-pentene, or mixtures thereof.