Claims
- 1. A water-soluble, biodegradable corrosion inhibitor composition comprising (1) an N-ethoxy,2-substituted imidazoline of the formula: ##STR3## wherein R is a divalent organic moiety, M' is selected from the group consisting of --O--, .dbd.N(CH.sub.2 CH.sub.2 O).sub.y --H and --S--, x is 0 or 1, each y is independently an integer from 0 to about 30 such that the group --(RM').sub.x --(CH.sub.2 CH.sub.2 O).sub.y --H and contains a total of 1 to about 30 ethoxy units and R' is an unsaturated or polyunsaturated fatty chain of from about six to about thirty carbons, (2) a phosphate ester derived from a water-soluble oxyethylated, straight chain alcohol of from about two to about thirty carbons, and (3) a solvent selected from the group consisting of water, ethylene glycol and propylene glycol.
- 2. A corrosion inhibitor as set forth in claim 1 wherein the corrosion inhibitor has an EC.sub.50 for Skeletonema costatum greater than 1 ppm by weight.
- 3. A composition as set forth in claim 1 wherein R is ethylene or --(CH.sub.2 CH.sub.2 O).sub.n (CH.sub.2 CH.sub.2)--, wherein n is an integer from one to seventeen.
- 4. A method for inhibiting corrosion of a metal surface in an aqueous liquid containing Skeletonema costatum, fish, algae or a combination thereof, the method comprising incorporating into the liquid an amount of a water-soluble corrosion inhibitor sufficient to inhibit corrosion of the metal surface, the corrosion inhibitor comprising (1) an N-ethoxy,2-substituted imidazoline of the formula: ##STR4## wherein R is a divalent organic moiety, M' is selected from the group consisting of --O--, N(CH.sub.2 CH.sub.2 O).sub.y --H, and --S--, x is 0 or 1, each y is independently an integer from 0 to 30 such that the group --(RM').sub.x --(CH.sub.2 CH.sub.2 O).sub.y --H contains a total of 1 to 30 ethoxy units and R' is an unsaturated or polyunsaturated fatty chain of from six to thirty carbons, and (2) a phosphate ester derived from a water-soluble oxyethylated, straight chain alcohol of from two to thirty carbons.
- 5. A method as set forth in claim 4 wherein the corrosion inhibitor further comprises a solvent selected from the group consisting of water, ethylene glycol and propylene glycol.
- 6. A method as set forth in claim 4 wherein the fatty chain is straight and has from twelve to twenty carbons.
- 7. A method as set forth in claim 6 wherein the fatty chain is the residue from a fatty acid selected from the group consisting of oleic acid, linoleic acid and eladeic acid.
- 8. A method as set forth in claim 6 wherein each y is an integer from two to eighteen.
- 9. A method as set forth in claim 4 wherein the liquid is sweet.
- 10. A method as set forth in claim 4 wherein the corrosion inhibitor has an EC.sub.50 for Skeletonema costatum greater than 1 ppm by weight.
- 11. A method as set forth in claim 4 wherein x is 1 and R is selected from the group consisting of alkylenes, arylenes and aralkylenes.
- 12. A method as set forth in claim 11 wherein R is ethylene, isopropylene or --(CH.sub.2 CH.sub.2 O).sub.n (CH.sub.2 CH.sub.2)--, wherein n is an integer from one to thirty.
- 13. A method as set forth in claim 12 wherein R is ethylene or --(CH.sub.2 CH.sub.2 O).sub.n (CH.sub.2 CH.sub.2)--, wherein n is an integer from one to seventeen.
- 14. A method for inhibiting corrosion of a metal surface in a aqueous liquid containing Skeletonema costatum, fish, algae or a combination thereof, the method comprising incorporating into the liquid an amount of a water-soluble corrosion inhibitor sufficient to inhibit corrosion of a metal surface, the corrosion inhibitor comprising an N-ethoxy,2-substituted imidazoline of the formula: ##STR5## wherein R is a divalent organic moiety, M' is selected from the group consisting of --O--, .dbd.NH(CH.sub.2 CH.sub.2 O).sub.y --H and --S--, x is 0 or 1, each y is independently an integer from 0 to 30 such that the group --(RM).sub.x --(CH.sub.2 CH.sub.2 O).sub.y --H contains a total of 1 to about 30 ethoxy units and R' is an unsaturated or polyunsaturated fatty chain of from about six to about thirty carbons.
- 15. A method as set forth in claim 14 wherein the liquid is sour and the corrosion inhibitor further comprises a phosphate ester derived from a water-soluble oxyethylated, straight chain alcohol of from two to thirty carbons.
- 16. A method as set forth in claim 15 wherein the imidazoline and the phosphate ester are present in the corrosion inhibitor in a weight ratio of from 1:1 to 4:1.
- 17. A method as set forth in claim 15 wherein the corrosion inhibitor further comprises a solvent selected from the group consisting of water, ethylene glycol and propylene glycol.
- 18. A method as set forth in claim 17 wherein R is ethylene or --(CH.sub.2 CH.sub.2 O).sub.n (CH.sub.2 CH.sub.2)--, wherein n is an integer from one to seventeen.
- 19. A method as set forth in claim 18 wherein the corrosion inhibitor further comprises a solvent selected from the group consisting of water, ethylene glycol and propylene glycol.
- 20. A method as set forth in claim 18 wherein the fatty chain is straight and has from about twelve to twenty carbons.
- 21. A method as set forth in claim 20 wherein the fatty chain is the residue from a fatty acid selected from the group consisting of oleic acid, linoleic acid and eladeic acid.
- 22. A method as set forth in claim 20 wherein each y is an integer from two to eighteen.
- 23. A method as set forth in claim 18 wherein the liquid is sweet.
- 24. A method as set forth in claim 18 wherein the corrosion inhibitor has an EC.sub.50 for Skeletonema costatum greater than 1 ppm by weight.
- 25. A method as set forth in claim 14 wherein the fatty chain is straight and has from twelve to twenty carbons.
- 26. A method as set forth in claim 25 wherein the fatty chain is the residue from a fatty acid selected from the group consisting of oleic acid, linoleic acid and eladeic acid.
- 27. A method as set forth in claim 25 wherein each y is an integer from two to eighteen.
- 28. A method as set forth in claim 14 wherein the corrosion inhibitor has an EC.sub.50 for Skeletonema costatum greater than 1 ppm by weight.
- 29. A method as set forth in claim 14 wherein R is ethylene or --(CH.sub.2 CH.sub.2 O).sub.n (CH.sub.2 CH.sub.2)--, wherein n is an integer from one to seventeen.
- 30. A method as set forth in claim 29 wherein the liquid is sour and the corrosion inhibitor further comprises a phosphate ester derived from a water-soluble oxyethylated, straight chain alcohol of from two to thirty carbons.
- 31. A method as set forth in claim 30 wherein the imidazoline and the phosphate ester are present in the corrosion inhibitor in a weight ratio of from 1:1 to 4:1.
- 32. A method as set forth in claim 30 wherein the corrosion inhibitor further comprises a solvent selected from the group consisting of water, ethylene glycol and propylene glycol.
- 33. A method as set forth in claim 29 wherein the fatty chain is straight and has from twelve to twenty carbons.
- 34. A method as set forth in claim 33 wherein the fatty chain is the residue from a fatty acid selected from the group consisting of oleic acid, linoleic acid and eladeic acid.
- 35. A method as set forth in claim 33 wherein the N-ethoxy substituent has from two to eighteen ethoxy units.
- 36. A method as set forth in claim 29 wherein the corrosion inhibitor has an EC.sub.50 for Skeletonema costatum greater than 1 ppm by weight.
Parent Case Info
This is a continuation application of U.S. application Ser. No. 08/394,126, filed Feb. 24, 1995, now abandoned (which is a continuation application of U.S. Ser. No. 08/146,900, filed Nov. 2, 1993, now U.S. Pat. No. 5,393,464).
US Referenced Citations (25)
Foreign Referenced Citations (3)
Number |
Date |
Country |
1.158.594 |
Jun 1958 |
FRX |
1. 103. 713 |
Mar 1961 |
DEX |
2 104 897 |
Mar 1983 |
GBX |
Continuations (2)
|
Number |
Date |
Country |
Parent |
394126 |
Feb 1995 |
|
Parent |
146900 |
Nov 1993 |
|