Modified acid compositions as alternatives to conventional acids in the oil and gas industry
An aqueous modified acid composition for industrial activities, said composition comprising: an alkanolamine and strong acid in a molar ratio of not less than 1:15, preferably not less than 1:10; it can also further comprise a metal iodide or iodate. Said composition demonstrates advantages over known conventional acids and modified acids.
1. A method of use of a modified acid composition comprising:
providing an aqueous modified acid composition comprising a mineral acid and an alkanolamine in a molar ratio ranging from 3:1 to not more than 15:1 and having a pH of less than 1;
contacting a surface of the aqueous modified acid composition;
allowing the aqueous modified acid composition to act upon said surface;
removing the acid composition when an exposure time has been determined to be sufficient for the operation to be complete or sufficiently complete; and
wherein said method of use includes at least one of etching concrete or cleaning concrete from equipment and buildings.
2. The method according to claim 1 , wherein the mineral acid is selected from the group consisting of: HCl, nitric acid, sulfuric acid, sulfonic acid, phosphoric acid, and combinations thereof.
3. The method according to claim 1 , wherein the mineral acid is hydrochloric acid.
4. The method according to claim 1 , wherein the hydrochloric acid and alkanolamine are present in a molar ratio of not more than 10:1.
5. The method according to claim 1 , wherein the hydrochloric acid and alkanolamine are present in a molar ratio of not more than 7.0:1.
6. The method according to claim 1 , wherein the hydrochloric acid and alkanolamine are present in a molar ratio of not more than 4.1:1.
7. The method according to claim 1 , wherein the alkanolamine is selected from the group consisting of: monoethanolamine; diethanolamine; triethanolamine and combinations thereof.
8. The method according to claim 1 , wherein the alkanolamine is monoethanolamine.
9. The method according to claim 1 , wherein the alkanolamine is diethanolamine.
10. The method according to claim 1 , wherein the modified acid composition further comprises a corrosion inhibitor comprising a α,β-unsaturated aldehyde with no methyl group at the alpha position.
11. A method of use of a modified acid composition comprising:
providing an aqueous modified acid composition comprising a mineral acid and an alkanolamine in a molar ratio ranging from 3:1 to not more than 15:1 and having a pH of less than 1;
contacting a surface of the aqueous modified acid composition;
allowing the aqueous modified acid composition to act upon said surface;
removing the acid composition when an exposure time has been determined to be sufficient for the operation to be complete or sufficiently complete; and
wherein said method of use includes at least one of descaling pipelines and related equipment or descaling facilities.
12. The method according to claim 11 , wherein the mineral acid is selected from the group consisting of: HCl, nitric acid, sulfuric acid, sulfonic acid, phosphoric acid, and combinations thereof.
13. The method according to claim 11 , wherein the mineral acid is hydrochloric acid.
14. The method according to claim 11 , wherein the hydrochloric acid and alkanolamine are present in a molar ratio of not more than 10:1.
15. The method according to claim 11 , wherein the hydrochloric acid and alkanolamine are present in a molar ratio of not more than 7.0:1.
16. The method according to claim 11 , wherein the hydrochloric acid and alkanolamine are present in a molar ratio of not more than 4.1:1.
17. The method according to claim 11 , wherein the alkanolamine is selected from the group consisting of: monoethanolamine; diethanolamine; triethanolamine and combinations thereof.
18. The method according to claim 11 , wherein the alkanolamine is monoethanolamine.
19. The method according to claim 11 , wherein the alkanolamine is diethanolamine.
20. The method according to claim 11 , wherein the modified acid composition further comprises a corrosion inhibitor comprising a α, β-unsaturated aldehyde with no methyl group at the alpha position.