Corrosion inhibitors for fuels and lubricants

Patent metadata

Field	Value
Publication number	US-11078418-B2
Application number	US-201716313751-A
Country	US
Kind code	B2
Filing date	Jun 27, 2017
Priority date	Jul 5, 2016
Publication date	Aug 3, 2021
Grant date	Aug 3, 2021

Abstract

The present invention relates to novel uses of corrosion inhibitors in fuels and lubricants.

First claim

The invention claimed is:

1. A process of reducing corrosion on a surface comprising iron, steel, copper, or a copper alloy, the process comprising:
contacting the surface with a corrosion inhibitor in the presence of sodium, potassium, magnesium, calcium, and/or zinc ions,
wherein the corrosion inhibitor comprises a reaction product of polyisobutene comprising free acid groups, the reaction product comprising, in reacted form: (A) a polyisobutene having a number-average molecular weight Mn in a range of from 200 to 10000 and (B) an α,β-unsaturated monomer that is a monocarboxylic acid, dicarboxylic acid, monoalkyl ester, dialkyl ester, or anhydride, in a stoichiometric ratio of more than one equivalent of the α,β-unsaturated monomer (B) per reactive double bond in the polyisobutene (A),
wherein the reaction product has a bismaleation level in a range of from at least 12% to 40%, and
wherein, when the monomer (B) comprises the monoalkyl ester and/or the dialkyl ester, at least 10% of the ester groups present in the reaction product are in hydrolyzed form, and/or
wherein, when the monomer (B) comprises the anhydride, at least 10% of the anhydride groups present in the reaction product are in hydrolyzed form.

2. The process of claim 1 , wherein the polyisobutene (A) has a number-average molecular weight M n of 500 to 2500.

3. The process of claim 1 , wherein the monomer (B) is selected from the group consisting of acrylic acid, methacrylic acid, crotonic acid, ethylacrylic acid and derivatives thereof.

4. The process of claim 1 , wherein the monomer (B) is selected from the group consisting of maleic acid, fumaric acid, itaconic acid (2-methylenebutanedioic acid), citraconic acid (2-methylmaleic acid), glutaconic acid (pent-2-ene-1,5-dicarboxylic acid), 2,3-dimethylmaleic acid, 2-methyl-fumaric acid, 2,3-dimethylfumaric acid, methylenemalonic acid, tetrahydrophthalic acid, and derivatives thereof.

5. The process of claim 1 , wherein the monomer (B) is maleic anhydride.

6. The process of claim 1 , wherein the bismaleation level is at least 11%.

7. The process of claim 1 , wherein a proportion of unconverted polyisobutene in the reaction product is not more than 30% by weight.

8. The process of claim 1 , wherein the corrosion inhibitor is comprised in a gasoline fuel having a sodium content, a potassium content, or both, of at least 0.1 ppm by weight.

9. The process of claim 1 , wherein the corrosion inhibitor is comprised in a gasoline fuel having a magnesium content, a calcium content, or both, of at least 0.1 ppm by weight.

10. The process of claim 1 , wherein the corrosion inhibitor is comprised in a gasoline fuel having a zinc content of at least 0.1 ppm by weight.

11. The process of claim 1 , wherein the reducing of corrosion comprises preventing and reducing deposits in a fuel system.

12. The process of claim 1 , wherein the bismaleation level is at least 15%.

13. The process of claim 1 , wherein the bismaleation level is up to 35%.

14. The process of claim 1 , wherein the bismaleation level is up to 30%.

15. The process of claim 1 , wherein the polyisobutene (A) has a number-average molecular weight Mn of 700 to 2500.

16. The process of claim 1 , wherein the polyisobutene (A) has a number-average molecular weight Mn up to 1100.

17. The process of claim 1 , wherein the compound (B) comprises acrylic acid and/or methacrylic acid.

18. The process of claim 1 , wherein the compound (B) comprises crotonic acid and/or ethylacrylic acid.

Assignees

• Basf Se

Inventors

• Mezger Jochen
• Csihony Szilard

Classifications

• C10L10/04

  for minimising corrosion or incrustation · CPC title

• C10N2030/12

  Inhibition of corrosion, e.g. anti-rust agents or anti-corrosives · CPC title

• C10L1/1883

  polycarboxylic acid · CPC title

• C10N2020/04

  Molecular weight; Molecular weight distribution · CPC title

• C09K15/06 Primary

  containing oxygen · CPC title