Quaternary and cationic ammonium surfactants as corrosion inhibitors
View Patent ↗Disclosed herein are corrosion inhibiting compounds and compositions useful in applications relating to the production, transportation, storage, and separation of crude oil and natural gas. Also disclosed herein are methods of using the compounds and compositions as corrosion inhibitors, particularly in applications relating to the production, transportation, storage, and separation of crude oil and natural gas.
1. A method of inhibiting corrosion at a surface, the method comprising contacting the surface with an amount of a compound of formula (I) effective in inhibiting corrosion at the surface, the compound of formula (I) being:
wherein
R 1 is C 1 -C 6 alkyl, C 1 -C 6 alkenyl, C 1 -C 6 alkynyl, C 3 -C 8 cycloalkyl, or benzyl;
R 2 is C 4 -C 6 alkyl, C 1 -C 6 alkenyl, C 1 -C 6 alkynyl, or C 3 -C 8 cycloalkyl;
R 3 is H, C 1 -C 6 alkyl, C 1 -C 6 alkenyl, C 1 -C 6 alkynyl, C 3 -C 8 cycloalkyl, or benzyl;
R 4 is —(CH 2 ) t —, —[CH 2 —(CHR 6 ) t ]—, or —[CH 2 —CHR 6 O) u —(CH 2 ) t ]—;
R 5 is C 4 -C 20 alkyl or C 4 -C 20 alkenyl;
R 6 is H, C 1 -C 6 alkyl, C 1 -C 6 alkenyl, C 1 -C 6 alkynyl, or C 3 -C 8 cycloalkyl;
A is N or P;
X is a counterion;
t is an integer independently selected from 1, 2, 3, 4, 5, and 6; and
u is an integer independently selected from 1, 2, 3, 4, 5, and 6.
2. The method of claim 1 , wherein R 5 is C 4 -C 20 alkyl.
3. The method of claim 1 , wherein R 5 is a saturated or unsaturated C 8 , C 10 , C 12 , C 14 , C 16 , or C 18 .
4. The method of claim 1 , wherein
R 1 is n-butyl;
R 2 is n-butyl;
R 3 is H;
R 4 is —CH 2 CH 2 —; and
X is acetate anion.
5. The method of claim 4 , wherein R 5 is —C 12 H 25 or —C 14 H 29 .
6. The method of claim 1 , further comprising co-administering with the compound of formula (I) an effective amount of a corrosion inhibitor synergist.
7. The method of claim 6 , wherein the corrosion inhibitor synergist is 2-mercaptoethanol.
8. The method of claim 1 , wherein the compound of formula (I) provides at least 88% 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 100, 500, 1,000, 5,000, 7,500, or 15,000 ppm based on total fluids.
9. The method of claim 8 , wherein the compound of formula (I) provides about 88-98% corrosion protection.
10. The method of claim 8 , wherein
R 1 is n-butyl;
R 2 is n-butyl;
R 3 is H;
R 4 is —CH 2 CH 2 —;
R 5 is —C 12 H 25 ; and
X is acetate anion.
11. The method of claim 1 , wherein the compound of formula (I) provides at least 80% protection after two hours, at least 85% protection after 8 hours, and about 100% protection after 21 hours for a 1018 carbon steel working electrode in a bubble test, wherein the bubble test is characterized by:
(a) a testing temperature of about 60° C.;
(b) a CO 2 saturated liquid medium of 20% LVT-200 oil and 80% ASTM Seawater brine; and
(c) an inhibitor dosage of 7,500 ppm based on total fluids.
12. The method of claim 11 , wherein the compound of formula (I) provides about 82.0% protection after two hours, about 87.3% protection after 8 hours, and about 100.0% protection after 21 hours.
13. The method of claim 11 , wherein
R 1 is n-butyl;
R 2 is n-butyl;
R 3 is H;
R 4 is —CH 2 CH 2 —;
R 5 is —C 12 H 25 ; and
X is acetate anion.
14. The method of claim 1 , wherein the surface is part of an apparatus used in the production, transportation, storage, and/or separation of crude oil and natural gas.
15. The method of claim 1 , comprising contacting the surface with an effective amount of a mixture of compounds of formula (I), said mixture represented by formula (I-i),
wherein coco is about 6% hexyl (C 6 ), about 7% decyl (C 10 ), about 51% dodecyl (C 12 ), about 19% tetradecyl (C 14 ), about 9% hexadecyl (C 16 ), about 2% octadecyl (C 18 ), and about 6% combined content of octadecenyl (C 18 ) and octadecadienyl (C 18 ).
16. A method of inhibiting corrosion on a surface of a solid at least partially submerged in a fluid, the method comprising adding to the fluid an amount of a composition comprising a compound of formula (I) effective in inhibiting corrosion on the surface of the solid, the compound being:
wherein
R 1 is C 1 -C 6 alkyl, C 1 -C 6 alkenyl, C 1 -C 6 alkynyl, C 3 -C 8 cycloalkyl, or benzyl;
R 2 is C 4 -C 6 alkyl, C 1 -C 6 alkenyl, C 1 -C 6 alkynyl, or C 3 -C 8 cycloalkyl;
R 3 is H, C 1 -C 6 alkyl, C 1 -C 6 alkenyl, C 1 -C 6 alkynyl, C 3 -C 8 cycloalkyl, or benzyl;
R 4 is —(CH 2 ) t —, —[CH 2 —(CHR 6 ) t ]—, or —[(CH 2 —CHR 6 O) u —(CH 2 ) t ]—;
R 5 is C 4 -C 20 alkyl or C 4 -C 20 alkenyl;
R 6 is H, C 1 -C 6 alkyl, C 1 -C 6 alkenyl, C 1 -C 6 alkynyl, or C 3 -C 8 cycloalkyl;
A is N or P;
X is a counterion;
t is an integer independently selected from 1, 2, 3, 4, 5, and 6; and
u is an integer independently selected from 1, 2, 3, 4, 5, and 6.
17. The method of claim 16 , wherein the composition further comprises one or more additional components, each component independently selected from the group consisting of synergistic compounds, asphaltene inhibitors, paraffin inhibitors, corrosion inhibitors, scale inhibitors, emulsifiers, water clarifiers, dispersants, emulsion breakers, hydrogen sulfide scavengers, gas hydrate inhibitors, biocides, pH modifiers, surfactants, and solvents.
18. The method of claim 16 , wherein the composition comprises a mixture of compounds of formula (I), said mixture represented by formula (I-i),
wherein coco is about 6% hexyl (C 6 ), about 7% decyl (C 10 ), about 51% dodecyl (C 12 ), about 19% tetradecyl (C 14 ), about 9% hexadecyl (C 16 ), about 2% octadecyl (C 18 ), and about 6% combined content of octadecenyl (C 18 ) and octadecadienyl (C 18 ).
19. The method of claim 16 , wherein the composition provides at least 88% 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 100, 500, 1,000, 5,000, 7,500, or 15,000 ppm based on total fluids.
20. The method of claim 16 , wherein the composition provides about 98% protection after two hours, about 99% protection after 8 hours, and about 100% protection after 21 hours for a 1018 carbon steel working electrode in a bubble test, wherein the bubble test is characterized by:
(a) a testing temperature of about 60° C.;
(b) a CO 2 saturated liquid medium of 20% LVT-200 oil and 80% ASTM Seawater brine; and
(c) an inhibitor dosage of 7,500 ppm based on total fluids.
21. The method of claim 1 wherein
R 1 is C 1 -C 6 alkyl;
R 2 is C 4 -C 6 alkyl;
R 3 is H or C 1 -C 6 alkyl;
R 4 is —CH 2 CH 2 —;
R 5 is C 4 -C 20 alkyl; and
A is N.
22. The method of claim 16 wherein
R 1 is C 1 -C 6 alkyl;
R 2 is C 4 -C 6 alkyl;
R 3 is H or C 1 -C 6 alkyl;
R 4 is —CH 2 CH 2 —;
R 5 is C 4 -C 20 alkyl; and
A is N.
23. The method of claim 1 , wherein the amount of the compound is from about 100 ppm to about 45,000 ppm.
24. The method of claim 1 , wherein the amount of the compound is from about 5,000 ppm to about 20,000 ppm.