Heat transfer methods, systems and compositions
Disclosed are methods for providing heating and/or cooling of the type comprising evaporating refrigerant liquid and condensing refrigerant vapor in a plurality of repeating cycles, where the method comprises (a) providing the refrigerant comprising at least about 5% by weight of a lower alkyl iodofluorocarbon; and (b) exposing at least a portion of said refrigerant in at least a portion of said plurality of said cycles to a sequestration material comprising: i) copper or a copper alloy; ii) a molecular sieve (preferably a zeolite), comprising copper, silver, lead or a combination thereof; iii) an anion exchange resin, and iv) a combination of two or more of these, wherein said exposing temperature is preferably above about 20 C.
1. A method for providing heat transfer of the type comprising providing a heat transfer composition comprising refrigerant and lubricant and evaporating refrigerant liquid to produce a refrigerant vapor, compressing in a lubricated compressor at least a portion of the refrigerant vapor and condensing in a condenser refrigerant vapor containing lubricant in a plurality of repeating cycles, said method comprising:
(a) providing a refrigerant comprising at least about 5% by weigh of a lower alkyl iodofluorocarbon;
(b) optionally providing lubricant for said compressor;
(c) providing an oil separator and a liquid line downstream of said compressor for returning lubricant to said compressor;
(b) exposing at least a portion of said refrigerant and/or at least a portion of said lubricant in at least a portion of said plurality of said cycles to a sequestration material comprising activated alumina,
wherein said exposing temperature is above about 10° C. and wherein said sequestration material is located at least in said oil separator and/or in said liquid line.
2. The method of claim 1 , wherein the sequestration material further comprises copper, or a copper alloy, preferably copper.
3. The method of claim 1 , wherein the sequestration material further comprises a molecular sieve and wherein said molecular sieve is a zeolite.
4. The method of claim 1 wherein the sequestration material further comprises a molecular sieve comprising copper, silver, lead or a combination thereof.
5. The method of claim 1 wherein the sequestration material further comprises an anion exchange resin.
6. The composition of claim 1 , wherein the sequestration material further comprises an anion exchange resin.
7. The method of claim 1 , wherein the sequestration material further comprises copper, or a copper alloy and a molecular sieve comprising copper, silver, lead or a combination thereof.
8. The method composition of claim 1 , wherein the sequestration material further comprises a zeolite molecular sieve comprising copper, silver, lead or a combination thereof, an anion exchange resin, and a moisture-removing material.
9. The method of claim 8 wherein said sequestration material is included in a filter element.
10. The method of claim 8 were said sequestration material is in the form of a solid core.
11. The method of claim 1 were said sequestration material solid carp is further located in a liquid line of said condenser.
12. The method of claim 1 were said sequestration material is in the form of a solid core located in said oil separator.
13. The method of claim 1 wherein when the sequestration material further comprises an anion exchange resin, the anion exchange resin comprises a positively charged matrix and exchangeable anions selected from chloride anions (Cl − ) or hydroxide anions (OH − ).
14. The method of claim 1 wherein when the sequestration material further comprises an anion exchange resin and wherein the anion exchange resin is a weakly basic anion exchange resin.
15. The method of claim 1 wherein when the sequestration material further comprises copper or a copper alloy, the copper or copper alloy has a surface area of from about 0.01 to about 1.5 m 2 per kg of refrigerant.
16. The method of claim 1 , wherein the sequestration material further comprises a molecular sieve and wherein said molecular sieve is a zeolite.
17. The method of claim 1 wherein the sequestration material further comprises a molecular sieve comprising copper, silver, lead or a combination thereof.
18. The method of claim 1 wherein the sequestration material further comprises an anion exchange resin.
19. A method for providing heat transfer of the type comprising evaporating refrigerant liquid to produce a refrigerant vapor, compressing in a compressor at least a portion of the refrigerant vapor and condensing refrigerant vapor from the compressor in a condenser and providing a liquid line for transporting refrigerant to the evaporator in a plurality of repeating cycles, said method comprising:
(a) providing a refrigerant comprising at least about 5% by weigh of a lower alkyl iodofluorocarbon;
(b) exposing at least said refrigerant to a sequestration material comprising activated alumina, wherein said sequestration material is located in said liquid line.