Cleaning compositions and methods for cleaning engine cooling systems
View Patent ↗Cleaning compositions include (a) a carrier liquid; (b) a metal citrate and/or a plurality of reagents configured to generate the metal citrate in situ; (c) one or a plurality of non-ionic surfactants; and (d) an organophosphate hydrotrope configured to increase solubility of the one or the plurality of non-ionic surfactants in the carrier liquid. Methods for cleaning engine cooling systems are described.
1. A cleaning composition configured to remove a corrosion by-product and/or hydrocarbon contamination from an engine cooling system, the composition comprising:
(a) a carrier liquid;
(b) a metal citrate and/or a plurality of reagents configured to generate the metal citrate in situ;
(c) one or a plurality of non-ionic surfactants; and
(d) an organophosphate hydrotrope configured to increase solubility of the one or the plurality of non-ionic surfactants in the carrier liquid;
wherein a pH of the cleaning composition ranges from about 9.0 to about 10.0.
2. The cleaning composition of claim 1 wherein the carrier liquid comprises water.
3. The cleaning composition of claim 2 wherein the water is deionized water, demineralized water, softened water, or a combination thereof.
4. The cleaning composition of claim 1 wherein the metal comprises an alkali metal.
5. The cleaning composition of claim 1 wherein the metal comprises an alkaline earth metal.
6. The cleaning composition of claim 1 wherein the metal citrate comprises sodium citrate.
7. The cleaning composition of claim 1 wherein the plurality of reagents comprises citric acid and a base.
8. The cleaning composition of claim 1 wherein the plurality of reagents comprises citric acid and sodium hydroxide.
9. The cleaning composition of claim 1 wherein a pH of the composition is about 9.5.
10. The cleaning composition of claim 1 wherein the one or the plurality of non-ionic surfactants comprises one or a plurality of C 12 -C 15 non-ionic surfactants.
11. The cleaning composition of claim 1 wherein the one or the plurality of non-ionic surfactants comprises a C 12 -C 15 fatty alcohol polyglycol ether.
12. The cleaning composition of claim 1 wherein the one or the plurality of non-ionic surfactants comprises a lauryl alcohol ethoxylate.
13. The cleaning composition of claim 1 wherein each of the one or the plurality of non-ionic surfactants has a hydrophile-lipophile balance (HLB) ranging from about 7.5 to about 13.0.
14. The cleaning composition of claim 1 wherein the one or the plurality of non-ionic surfactants comprises a first lauryl alcohol ethoxylate having an HLB of about 12.4 and a second lauryl alcohol ethoxylate having an HLB of about 8.0.
15. The cleaning composition of claim 1 wherein the organophosphate hydrotrope comprises an aromatic phosphate ester salt.
16. The cleaning composition of claim 1 wherein the organophosphate hydrotrope comprises an aromatic phosphate ester potassium salt.
17. The cleaning composition of claim 1 further comprising a glycol ether coupling agent.
18. The cleaning composition of claim 17 wherein the glycol ether coupling agent comprises butyl carbitol.
19. The cleaning composition of claim 1 further comprising a biocide agent, an antifoam agent, a dye, or a combination thereof.
20. A cleaning composition configured to remove a corrosion by-product and/or hydrocarbon contamination from an engine cooling system, the composition comprising:
(a) water in an amount ranging from about 60 wt. % to about 80 wt. % based on a total weight of the cleaning composition;
(b) citric acid in an amount ranging from about 8 wt. % to about 12 wt. % based on the total weight of the cleaning composition;
(c) an alkali metal hydroxide in an amount ranging from about 4 wt. % to about 8 wt. % based on the total weight of the cleaning composition;
(d) a first lauryl alcohol ethoxylate surfactant having an HLB of greater than about 10.0 and a second lauryl alcohol ethoxylate surfactant having an HLB of less than about 10.0, wherein the first lauryl alcohol ethoxylate surfactant and the second lauryl alcohol ethoxylate surfactant are present in a combined amount ranging from about 4 wt. % to about 6 wt. % based on the total weight of the cleaning composition; and
(e) an aromatic phosphate ester salt in an amount ranging from about 5 wt. % to about 7 wt. % based on the total weight of the cleaning composition;
wherein a pH of the cleaning composition ranges from about 9.0 to about 10.0.
21. The cleaning composition of claim 20 further comprising a glycol ether coupling agent in an amount ranging from about 1 wt. % to about 3 wt. % based on the total weight of the cleaning composition.
22. The cleaning composition of claim 21 further comprising a biocide agent, an antifoam agent, and a dye in a combined amount ranging from about 0.10 wt. % to about 0.50 wt. % based on the total weight of the cleaning composition.
23. A cleaning composition prepared by a process comprising combining water, citric acid, an alkali metal hydroxide, one or a plurality of C 12 -C 15 non-ionic surfactants, and an organophosphate hydrotrope to form a solution having a pH of between about 9.0 and about 10.0.