Heat transfer fluid additive composition
View Patent ↗Disclosed herein is a heat transfer fluid additive composition comprising: greater than or equal to 10 weight percent (wt %) of a carboxylic acid, based on the total weight of the composition; an azole compound; and a base, wherein the base is present in an amount sufficient to obtain a pH 8-10.5 when diluted by 50 volume % with water. The heat transfer fluid additive composition can be combined with other components to form a heat transfer fluid. The heat transfer fluid can be used in a heat transfer system.
1. A heat transfer fluid additive composition consisting of:
greater than or equal to about 10 wt % of an aliphatic carboxylate, based on the total weight of the composition;
an azole compound;
a base;
a glycol;
water; and
optionally, an antifoam, a dye, a surfactant, or combinations thereof, and
wherein the composition is free of silicate.
2. The additive composition of claim 1 , wherein the additive composition is free of borate and amines.
3. The additive composition of claim 1 , wherein the carboxylate is present in an amount greater than or equal to about 15 wt %, based on the total weight of the composition.
4. The additive composition of claim 1 , wherein the carboxylate is present in an amount greater than or equal to about 20 wt %, based on the total weight of the composition.
5. The additive composition of claim 1 , wherein the azole is present in an amount of about 0.01 to about 10 wt %, based on the total weight of the composition.
6. The additive composition of claim 1 , wherein the azole is present in an amount of about 0.3 to about 9 wt %, based on the total weight of the composition.
7. The additive composition of claim 1 , wherein the azole is present in an amount of about 0.5 to about 8 wt %, based on the total weight of the composition.
8. The additive composition of claim 1 , wherein the base is present in an amount sufficient to obtain a pH of about 7.5 to about 10.5 when the heat transfer additive composition is diluted by 50 volume % with water.
9. The additive composition of claim 1 , wherein the base is present in an amount sufficient to obtain a pH of about 8 to 10.5 when the heat transfer additive composition is diluted by 50 volume % with water.
10. The additive composition of claim 1 , wherein water is present in an amount of about 10 wt % to about 70 wt %, based on the total weight of the composition.
11. The additive composition of claim 1 , wherein water is present in an amount of about 10 wt % to about 50 wt %.
12. The additive composition of claim 1 , wherein water is present in an amount of about 10 wt % to about 40 wt %, based on the total weight of the composition.
13. The additive composition of claim 1 , wherein water is present in an amount of about 10 wt % to about 25 wt %, based on the total weight of the composition.
14. The additive composition of claim 1 , wherein the glycol is present in an amount of about 10 to about 85 wt %, based on the total weight of the composition.
15. The additive composition of claim 1 , wherein the glycol is present in an amount of about 10 to about 40 wt %, based on the total weight of the composition.
16. The additive composition of claim 1 , wherein the glycol is present in an amount of about 10 to about 20 wt %, based on the total weight of the composition.
17. A method of making a heat transfer fluid comprising combining the heat transfer fluid additive composition of claim 1 with water, a non-aqueous solvent, or a combination of water and a non-aqueous solvent.
18. The method of claim 17 , wherein the additive composition is free of borate and amines.
19. The method of claim 17 , wherein the carboxylate is present in an amount greater than or equal to about 15 wt %, based on the total weight of the additive composition.
20. The method of claim 17 , wherein the carboxylate is present in an amount greater than or equal to about 20 wt %, based on the total weight of the additive composition.
21. The method of claim 17 , wherein the azole is present in an amount of about 0.01 to about 10 wt %, based on the total weight of the additive composition.
22. The method of claim 17 , wherein the azole is present in an amount of about 0.5 to about 8 wt %, based on the total weight of the additive composition.
23. The method of claim 17 , wherein the base is present in an amount sufficient to obtain a pH of about 7.5 to about 10.5 when the heat transfer additive composition is diluted by 50 volume % with water.
24. The method of claim 17 , wherein the base is present in an amount sufficient to obtain a pH of about 8 to 10.5 when the heat transfer additive composition is diluted by 50 volume % with water.
25. The method of claim 17 , wherein water is present in the additive composition in an amount of about 10 wt % to about 70 wt %, based on the total weight of the composition.
26. The method of claim 17 , wherein water is present in the additive composition in an amount of about 10 wt % to about 50 wt %, based on the total weight of the additive composition.
27. The method of claim 17 , wherein water is present in the additive composition in an amount of about 10 wt % to about 40 wt %, based on the total weight of the additive composition.
28. The method of claim 17 , wherein water is present in the additive composition in an amount of about 10 wt % to about 25 wt %, based on the total weight of the additive composition.
29. The method of claim 17 , wherein the glycol is present in an amount of about 10 to about 40 wt %, based on the total weight of the composition.
30. A method of making a modified heat transfer fluid comprising combining the heat transfer fluid additive composition of claim 1 with an existing heat transfer fluid to form a modified heat transfer fluid.
31. The method of claim 30 , wherein the existing heat transfer fluid is not in contact with a heat transfer system.
32. The method of claim 30 , wherein the existing heat transfer fluid is in contact with a heat transfer system.
33. The heat transfer fluid additive composition of claim 1 , wherein the base is sodium hydroxide.
34. The method of claim 17 , wherein the base is sodium hydroxide.
35. The heat transfer fluid additive composition of claim 1 , wherein the glycol is ethylene glycol.
36. The method of claim 17 , wherein the glycol is ethylene glycol.
37. The heat transfer fluid additive composition of claim 1 , wherein the azole is sodium tolyltriazole.
38. The method of claim 17 , wherein the azole is sodium tolyltriazole.
39. The heat transfer fluid additive composition of claim 1 , wherein the carboxylate is neodecanoic acid and 2-ethyl hexanoic acid.
40. The method of claim 17 , wherein the carboxylate is neodecanoic acid and 2-ethyl hexanoic acid.
41. The heat transfer fluid additive composition of claim 1 , wherein the base is about 9 to about 12 weight percent.