Methods of inhibiting corrosion of metal surfaces by aqueous acids are described. The methods include combining an effective amount of a corrosion inhibitor composition with an aqueous acid solution to form an inhibited acid solution and contacting a metal surface with the inhibited acid solution. The corrosion inhibitor composition includes an aromatic ketone or a salt thereof.

An inhibition corrosion package for use with an acidic composition, where the package comprises a dialdehyde-containing hydrocarbon component; at least one surfactant; optionally, a propargyl alcohol or derivative thereof; and a solvent. Also disclosed are acidic compositions combining the corrosion inhibition package according to a preferred embodiment of the present invention for use in various industrial operations including but not limited to oil and gas operations. Also disclosed are methods of use of such compositions.

The present invention provides: a rust inhibitor that has excellent rust inhibiting and anti-corrosive properties, not only on iron members, but also on non-iron metal members, and can prevent rust and corrosion over long periods; a rust inhibitor composition that contains the rust inhibitor, a coating formation material; a coating obtained from the rust inhibitor, the rust inhibitor composition, or the coating formation material; and a metal component that comprises the coating. This rust inhibitor contains at least one compound represented by a Chemical Formula (1). ##STR00001##
(In the formula: R.sup.1 is a hydrogen atom or an aliphatic hydrocarbon group with a carbon number of 1-33; R.sup.2 is an aliphatic hydrocarbon group with a carbon number of 1-33; the total carbon number of R.sup.1 and R.sup.2 is 1-34; X is a single bond or an aliphatic hydrocarbon group with a carbon number of 1-5; either A.sup.1 or A.sup.2 is —OH; and the other is —O—CH.sub.2—CH(OH)—CH.sub.2OH or —O—CH(—CH.sub.2—OH).sub.2.)

A corrosion inhibitor composition, which includes (i) a date palm leaves extract, (ii) a benzimidazole compound having at least one a carbamate group, (iii) a pyridine compound, (iv) a thiourea compound, (v) a cinnamaldehyde compound, (vi) a metal iodide, (vii) urotropin, and (viii) a base fluid containing an alcohol and an organic acid. A method of inhibiting corrosion of metal during acid cleaning is also disclosed, whereby the metal is treated with an acidic treatment fluid containing 1 to 5 wt. % of an acid, based on a total weight of the acidic treatment fluid, and 0.1 to 5 vol. % of the corrosion inhibitor composition, based on a total volume of the acidic treatment fluid.

A nuclear power plant comprising a primary coolant circuit, a steam-water circuit separated from the primary coolant circuit and a steam generator connected to the primary coolant circuit and the steam-water circuit to transfer heat from the primary coolant circuit into the steam-water circuit has at least one dosing point in the steam-water circuit to inject a reducing agent into the steam-water circuit, wherein the reducing agent is an organic compound consisting of carbon, hydrogen and oxygen. Furthermore, a method for operating said nuclear power plant and the use of the method for downtime preservation of the secondary side of a steam generator of a nuclear power plant are provided.

Corrosion inhibition compositions and methods useful for inhibiting corrosion are provided. The corrosion inhibition compositions comprise at least one filming agent and at least one promoting agent and the methods for inhibiting corrosion on metal surfaces utilize the disclosed corrosion inhibiting compositions.

The present invention provides: a rust inhibitor that has excellent rust inhibiting and anti-corrosive properties, not only on iron members, but also on non-iron metal members, and can prevent rust, and corrosion over long periods; a rust, inhibitor composition that, contains the rust inhibitor, a coating formation material; a coating obtained from the rust inhibitor, the rust inhibitor composition, or the coating formation material; and a metal component that comprises the coating. This rust inhibitor contains at least one compound represented by a Chemical Formula (1).

##STR00001## (In the formula: R.sup.1 is a hydrogen atom or an aliphatic hydrocarbon group with a carbon number of 1-33; R.sup.2 is an aliphatic hydrocarbon group with a carbon number of 1-33; the total carbon number of R.sup.1 and R.sup.2 is 1-34; X is a single bond or an aliphatic: hydrocarbon group with a carbon number of 1-5; either A.sup.1 or A.sup.2 is —OH; and the other is —O—CH.sub.2—CH(OH)—CH.sub.2OH or —O—CH(—CH.sub.2—OH).sub.2.)

Method of minimizing pitting corrosion at temperatures above 130° C., wherein said method comprises: providing an acidic fluid comprising an alkylsulfonic acid; providing at least one corrosion inhibitor compound comprising an organic compound comprising at least two aldehyde functional groups; combining said acidic fluid with said at least one corrosion inhibitor compound; exposing said mixed fluid to a metallic surface at a temperature of at least 130° C.; and allowing said mixed fluid sufficient time of exposure to a metal to accomplish a pre-determined function.

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.

The present disclosure is directed to methods, systems and apparatuses for predictively selecting plant extracts for their inclusion in formulations to imparting anti-corrosion properties to coatings for aluminum, aluminum alloys, copper and copper alloys.