FIELD OF THE INVENTION

The present application is directed at inhibition or prevention of corrosion.

BACKGROUND

Corrosion of metal surfaces continues to be a problem in industries such as oil and gas and industrial water systems, in which the fluids can include “corrodents” such as salts or other dissolved solids, liquids, gases, or combination thereof that cause, accelerate, or promote corrosion of metal containments that contact the corrodents. Corrosion problems are even more troublesome in deep-sea operations where replacement of corroded equipment is difficult and costly. As a result, almost all operators in the oil and gas industry employ corrosion inhibitors to reduce corrosion in metal containments.

Filming corrosion inhibitors have been used to limit the corrosion of materials in industrial water systems. Generally, these filming corrosion inhibitors have properties that allow them to attach or bind to the metal and/or metal oxide surface to coat or cover and thereby limit the reduction/oxidation (redox) corrosion process between the water and the surface. An effective filming corrosion inhibitor in aqueous systems typically includes some degree of hydrophobicity. However, hydrophobicity can limit the applicability and utility of some substances in industrial water systems such as steam generators (e.g., boilers), heat exchange loops, and cooling water systems. Hydrophobicity can also limit the ability to blend or to make shelf and storage stable homogenous treatment products. The treatment products are generally aqueous based products and hydrophobic corrosion inhibitors can separate out of the treatment. Such lack of stability can result in periods of over feed (higher dosage) and periods of under feed (lesser dosage). The resulting variation in inhibitor feed can lead to increased corrosion in the industrial water treatment system.

Some aqueous hydrophobic filming corrosion inhibitors are formulated with additional solvents or co-solvents to aid in holding the inhibitor in the product thereby ensuring shelf stability. While these solvents may provide shelf stability, they may negatively affect the operation of the water treatment system, add additional risk of failure, and/or result in non-compliance with regulations. For example, N-oleyl-1,3-diaminopropane is a hydrophobic corrosion inhibitor that has been used in water treatment systems. N-oleyl-1,3-diaminopropane has been formulated with a solvent, e.g., cyclohexylamine, in sufficient concentration to provide a shelf stable product for feed and use in industrial water systems. But regulatory constraints placed on products containing cyclohexylamine (e.g., spill reporting requirements and or other hazards) discourage and often prevent the use of this combination. In other types of systems, such as high pressure utility or power steam generation systems, the eventual hydrothermal decomposition of the organic solvent, e.g., cyclohexylamine, also precludes the use of the combination product in those generators. Other materials that are used in utility or power steam generating systems are ethanolamine and ammonium hydroxide (i.e., aqueous ammonia), but neither are effective as solvents of N-oleyl-1,3-diaminopropane.

In view of these challenges, improved corrosion inhibitors are desirable.

SUMMARY

Described herein are compositions and methods for inhibiting corrosion in a fluid source. In some embodiments, the fluid source comprises water, gas, liquid hydrocarbon or combination thereof. Also described is shelf stable corrosion inhibitor without the use of solvents or co-solvents that negatively affect properties of a water system. In some embodiments, the corrosion inhibitor comprises a hydrophobic filming corrosion inhibitor which is shelf stable.

In one aspect of the invention is a method of inhibiting corrosion of metal containments in contact with a fluid source comprising the steps of:introducing into the fluid source a composition comprising one or more oleyl propylenediamine-based compounds.

In some embodiments, the oleyl propylenediamine-based compound is represented by Formula (I):



wherein Y1, Y2, and Y3independently are hydrogen or a substituent of Formula (II):



wherein V is −O— or —NH—, W is optionally present and is a linear or branched C1-10aliphatic group, X is —H, —NZ3+, —COOH, —SO3H, —PO3H, or a salt thereof, each Z independently is hydrogen or a linear or branched C1-20aliphatic group optionally interrupted or substituted with one or more oxygen atoms, and R is hydrogen or methyl, provided that at least one of Y1, Y2, or Y3is a substituent of Formula (II).

In another aspect of the invention is a composition for use as a corrosion inhibitor of a metal surface, comprising one or more compound(s) of Formula (I):



wherein Y1, Y2, and Y3independently are hydrogen or a substituent of Formula (II):



wherein V is −O— or —NH—, W is optionally present and is a linear or branched C1-10aliphatic group, X is —H, —NZ3+, —COOH, —SO3H, —PO3H, or a salt thereof, each Z independently is hydrogen or a linear or branched C1-20aliphatic group optionally interrupted or substituted with one or more oxygen atoms, and R is hydrogen or methyl, provided that at least one of Y1, Y2, or Y3is a substituent of Formula (II).

In another aspect of the invention is a composition for use as a corrosion inhibitor, comprising one or more compound(s) of Formula (I):

wherein Y1, Y2, and Y3independently are hydrogen or a substituent of Formula (II):

wherein V is −O— or —NH—, W is optionally present and is a linear or branched C1-10aliphatic group;X is —H, —NZ3+, —COOH, —SO3H, —PO3H, or a salt thereof;

each Z independently is hydrogen or a linear or branched C1-20aliphatic group optionally interrupted or substituted with one or more oxygen atoms; and

R is hydrogen or methyl, provided that at least one of Y1, Y2, or Y3is a substituent of Formula (II).

In some embodiments the oleyl propylenediamine-based compounds of Formula I also include Formula III.



In another aspect of the invention is the compound of Formula (I) can help to solubilize the compound of Formula (III), such that the compound of Formula (III) can also act as a corrosion inhibitor in the composition.

In another aspect of the invention is a composition that includes the oleyl propylenediamine-based compounds of Formula I and a fluid source. In some embodiments the fluid source is water, gas, optionally liquid hydrocarbon and combinations thereof. In some embodiments the water can contain dissolved solids and gasses.

In yet another aspect of the invention is a treated metal containment comprising:a metal containment comprising a metal surface; andthe fluid source comprising the oleyl propylenediamine-based compounds, wherein at least a portion of the metal surface is in contact with the fluid source.

In another aspect of the invention is the use of the oleyl propylenediamine-based compounds of formula I in an aqueous system to solubilize the oleyl propylenediamine-based compound of formula III:



