2-substituted benzimidazoles and methods of preparing the same are disclosed. The compositions may include a compound or salt thereof, a strong acid, and a carboxylic acid. The compositions may exclude a polar aprotic solvent. The compositions may be used to inhibit corrosion of a metal surface in contact with an aqueous system, and provide enhanced protection against corrosion of metals in the aqueous system.

Compositions and methods are provided for reducing, inhibiting, or preventing corrosion of a surface, the polyamine compounds corresponding to the structure of Formula 1 or 2, or a salt thereof:

##STR(1)##

wherein X.sub.1 is —C(O)R.sub.9 or —[C(R.sub.10R.sub.11)].sub.p—C(R.sub.12)(X.sub.2)—R.sub.13; X.sub.2 is —OH or —NH.sub.2; R.sub.1 and R.sub.4 are independently hydrogen, alkyl, or —[C(R.sub.10R.sub.11)].sub.p—C(R.sub.12)(X.sub.2)—R.sub.13; R.sub.2, R.sub.3, R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.10, R.sub.11, and R.sub.12 are independently hydrogen or alkyl; R.sub.9 and R.sub.13 are independently C.sub.7 to C.sub.30 alkyl or alkenyl; m and o are integers from 1 to 10; n is an integer from 1 to 6; and p is an integer from 1 to 10;

##STR(2)##

wherein X.sub.2 is —OH or —NH.sub.2; R.sub.21, R.sub.22, R.sub.23, R.sub.24, R.sub.25, R.sub.26, and R.sub.28 are independently hydrogen or alkyl; R.sub.27 is C.sub.10 to C.sub.30 alkyl or alkenyl; m and o are integers from 1 to 10; n is an integer from 1 to 6; and q is an integer from 0 to 10.

A method for improving the heating efficiency of steam wherein a polyamine represented by the following general formula (1) is caused to be present in a steam system to be used for heating. R.sup.1—[NH—(CH.sub.2).sub.m].sub.n—NH.sub.2 . . . (1) wherein R.sup.1 represents a saturated or unsaturated hydrocarbon group having 10 to 22 carbon atoms; m is an integer of 1 to 8, and n is an integer of 1 to 7; and when n is 2 or more, a plurality of NH—(CH.sub.2).sub.m may be identical or different.

Disclosed are corrosion inhibitor compounds and compositions useful for preventing or inhibiting corrosion of surfaces found in cooling water applications. In some embodiments, the surfaces may include mild steel, aluminum, brass, copper, galvanized steel, a copper alloy, admirality brass, or any combination thereof. Also disclosed are methods of using the compounds and compositions as corrosion inhibitors. In some embodiments, the corrosion inhibitor compounds and compositions are used in cooling water applications.

The present disclosure relates to agents, compositions, and methods for inhibiting corrosion in various substrates, for example in metal substrates. The present disclosure also relates to compositions for inhibiting corrosion comprising at least one organic heterocyclic compound and at least one metal salt or mixed metal salt selected from rare earth, alkali earth and transition metals.

Graphene quantum dots are functionalized by covalently bonding a corrosion inhibitor molecule thereto. In a useful method, a corrosion inhibitor compound is blended with a graphene quantum dot-tagged corrosion inhibitor compound, and the blend is applied to a metal surface, such as the interior of a carbon steel pipe. The blend inhibits corrosion arising from contact with produced water generated by hydrocarbon recovery from one or more subterranean reservoirs. The produced water having the blend dispersed therein is irradiated with a source of light having a selected first range of wavelengths, and the luminescent emission of the graphene quantum dot-tagged corrosion inhibitor is measured at a selected second range of wavelengths, thereby providing for real-time measurement of corrosion inhibitor concentration within the pipe.

Please replace the Abstract of the application as filed with the following replacement A coolant composition containing the following substances: a) an alcohol; b) water; c1) a triazole compound; c2) an imidazole compound; d) a phosphate ion; and e) a metasilicate.

A corrosion inhibition package for use with an aqueous acid composition, said package comprising: a terpene; a cinnamaldehyde or a derivative thereof; at least one amphoteric surfactant; and a solvent. Also disclosed are compositions comprising said corrosion inhibitor package. Preferably, the corrosion inhibition package meets the environmental requirements for classification as yellow according to the Norwegian North Sea offshore drilling regulatory requirements.

Methods for providing corrosion inhibition in conduits, containers, and wellbores penetrating subterranean formations are provided. In some embodiments, the methods comprise contacting a metal surface with a fluid comprising a corrosion inhibitor additive. In certain embodiments, the corrosion inhibitor additive comprises a compound comprising a hydrophobic cation moiety, one or more lipophilic tails, and a linking moiety.

A corrosion inhibitor composition, containing (a) a cinnamaldehyde compound, (b) an alkoxylated fatty amine, and (c) an imidazoline compound, and optionally (d) a surfactant, and (e) a solvent. A method of inhibiting corrosion of metal in contact with an acidic medium in an oil or gas field environment by introducing the corrosion inhibitor composition into the acidic medium, such as during acid stimulation operations.