Organic disulfide based corrosion inhibitors

1. A method of inhibiting corrosion at a surface, the method comprising contacting the surface with a composition comprising a compound of formula (I),

wherein,

R 1 and R 2 are each independently selected from the group consisting of alkyl, alkenyl, alkynyl, aryl, heteroaryl, heterocycle, and cycloalkyl, wherein said alkyl, alkenyl, alkynyl, aryl, heteroaryl, heterocycle, and cycloalkyl are each independently substituted or unsubstituted with one or more suitable substituents,

wherein the suitable substituent is selected from halo, perfluoroalkyl, perfluoroalkoxy, alkyl, alkenyl, alkynyl, hydroxy, oxo, mercapto, alkylthio, alkoxy, aryl, heteroaryl, aryloxy, heteroaryloxy, aralkyl, heteroaralkyl, aralkoxy, heteroaralkoxy, HO—(C═O)—, cycloalkyl, amino, alkylamino, dialkylamino, carbamoyl, alkylcarbonyl, alkoxycarbonyl, alkylaminocarbonyl, dialkylamino carbonyl, arylcarbonyl, aryloxycarbonyl, alkylsulfonyl, and arylsulfonyl;

with the proviso that the following compounds and their acid addition salts are excluded: cystine; cystamine; disulfides of 1-amino-2-methyl-2-thiopropane, 1-amino-3-thiopropane, 1-amino-4-thiobutane, 2-amino-3-methyl-1-thiobutane, 2-amino-1-thiohexane, 2-amino-3,3-dimethyl-1-thiobutane, 1-amino-2-thiopropane, 2-amino-3-methyl-3-thiobutanecarboxylic acid (penicillamine), 2-amino-3-thiobutanecarboxylic acid (homocysteine), 2-amino-2-methyl-1-thiopropane, 1-amino-2-thiohexane, 2-amino-1-thiohexadecane, 2-amino-3-thioadipic acid, 2-amino-3-thio-3-phenylpropanecarboxylic acid, 1-amino-2-thio-1,2-diphenylethane, and 2-(2-amino-1-thioethyl)-naphthalene; diethyl disulfide; di-n-propyl disulfide; diisopropyl disulfide; di-n-butyl disulfide; di-sec-butyl disulfide; diisobutyl disulfide; di-tert-butyl disulfide; di-n-pentyl disulfide; di-neopentyl disulfide; di-n-hexyl disulfide; di-n-heptyl disulfide; di-n-octyl disulfide; di-n-nonyl disulfide; di-n-decyl disulfide; di-n-dodecyl disulfide; di-n-tridecyl disulfide; di-n-tetradecyl disulfide; di-n-pentadecyl disulfide; di-n-hexadecyl disulfide; di-n-heptadecyl disulfide; di-n-octadecyl disulfide; di-n-decyl disulfide; diundecyl disulfide; didodecyl disulfide; dihexadecyl disulfide; diallyl disulfide; dibenzyl disulfide; 2-naphthyl disulfide; and dithienyl disulfide.

2. The method of claim 1 , wherein R 1 and R 2 are each independently selected from the group consisting of C 1 -C 10 -alkyl, C 6 -C 12 -aryl, monocyclic or bicyclic heteroaryl, and C 3 -C 8 -cycloalkyl, wherein said alkyl, aryl, heteroaryl, and cycloalkyl are each independently unsubstituted or substituted with 1 to 3 substituents independently selected from the group consisting of —F, —Cl, —NO 2 , —CN, —OH, —NH 2 , C 1 -C 6 haloalkyl, C 1 -C 6 alkoxy, —CO 2 R 3 , and —CON(R 4 ) 2 , wherein R 3 and R 4 , at each occurrence, are each independently selected from the group consisting of hydrogen and C 1 -C 6 alkyl.

3. The method of claim 2 , wherein the composition further comprises one or more additional components, each component independently selected from the group consisting of additional corrosion inhibitors, solvents, asphaltene inhibitors, paraffin inhibitors, scale inhibitors, emulsifiers, water clarifiers, dispersants, emulsion breakers, gas hydrate inhibitors, biocides, pH modifiers, and surfactants.

4. The method of claim 2 , wherein the composition provides at least 80% corrosion protection for a 1018 carbon steel coupon in a wheel box test, wherein the wheel box test is characterized by:

(a) a testing temperature of about 176° F.;

(b) a CO 2 saturated liquid medium of 10% LVT-200 oil and 90% ASTM Seawater brine;

(c) a test duration of 24 hours; and

(d) an inhibitor dosage of 20 ppm based on total fluids.

5. The method of claim 2 , wherein the composition provides at least 94% corrosion protection for a 1018 carbon steel coupon in a wheel box test, wherein the wheel box test is characterized by:

(a) a testing temperature of about 176° F.;

(b) a CO 2 saturated liquid medium of 10% LVT-200 oil and 90% ASTM Seawater brine;

(c) a test duration of 24 hours; and

(d) an inhibitor dosage of 2.5 ppm based on total fluids.

6. The method of claim 2 , wherein the surface is part of equipment used in the production, transportation, storage, and/or separation of crude oil or natural gas.

7. The method of claim 2 , wherein the surface is part of equipment used in a coal-fired process, a waste-water process, a farm, a slaughter house, a land-fill, a municipality waste-water plant, a coking coal process, or a biofuel process.

8. The method of claim 1 , wherein the composition provides 200 ppm or less of sulfur species in a headspace test, wherein the headspace test is characterized by:

(a) placing a sample of the composition into a sealed receptacle;

(b) aging the composition of (a) at a selected temperature for a selected time period; and

(c) sampling the headspace for sulfur species.

9. The method of claim 8 , wherein the composition comprises about 2.5% wt. of one or more compounds of formula (I) in a 1:1 water:glycol ether solvent system.

10. The method of claim 8 , wherein the composition comprises about 2.5% wt. of one or more compounds of formula (I) and about 7.5% wt. of a quaternary amine salt corrosion inhibitor in a 1:1 water:glycol ether solvent system.

11. The method of claim 1 , wherein R 1 and R 2 are each selected from C 1 -C 10 -alkyl, each optionally substituted with 1 to 3 substituents independently selected from the group consisting of —OH and —CO 2 H.

12. The method of claim 1 , wherein R 1 and R 2 are each selected from C 1 -C 10 -alkyl, each substituted with 1 to 3 substituents independently selected from the group consisting of —OH and —CO 2 H.

13. The method of claim 1 , wherein R 1 and R 2 are each selected from linear C 1 -C 10 -alkyl, each substituted with a terminal —OH group.

14. The method of claim 1 , wherein R 1 and R 2 are each selected from linear C 1 -C 10 -alkyl, each substituted with a terminal —CO 2 H group.

15. The method of claim 1 , wherein R 1 and R 2 are each selected from C 6 -C 12 -aryl, each optionally substituted with 1 to 3 substituents independently selected from the group consisting of —OH and —NH 2 .

16. The method of claim 1 , wherein R 1 and R 2 are each selected from phenyl, each optionally substituted with 1 to 3 substituents independently selected from the group consisting of —OH and —NH 2 .

17. The method of claim 1 , wherein R 1 and R 2 are each selected from phenyl, each substituted with an —NH 2 group.

18. The method of claim 1 , wherein R 1 and R 2 are each selected from phenyl, each substituted with an —OH group.

19. The method of claim 1 , wherein R 1 and R 2 are each selected from a 5- or 6-membered monocyclic heteroaryl, each optionally substituted with 1 to 3 suitable substituents.

20. The method of claim 1 , wherein the composition comprises one or more compounds of formula (I), each independently selected from the group consisting of: 2,2′-dithiodiethanol; 2,2′-dithiodiacetic acid; 3,3′-dithiodipropionic acid; 4,4′-dithiodibutyric acid; 3,3′-dihydroxydiphenyl disulfide; 4-aminophenyl disulfide; 2-aminophenyl disulfide; and 2,2′-dithiodipyridine.