A polyhydroxypolycarboxylic acid and a water soluble phosphino polycarboxylate may be added to an aqueous system, such as a cooling water system, in order to inhibit corrosion as well as the deposition of corrosion within the system. The water soluble phosphino polycarboxylate may be derived from a phosphinyl unsaturated monomer and an ethylenically unsaturated carboxylic acid monomer. The aqueous system may be a cooling water system such as a cooling tower, a closed cooling water system, an air-conditioning water systems, a wastewater treatment system as well as a deionized water production system.

A polyhydroxypolycarboxylic acid and a water soluble phosphino polycarboxylate may be added to an aqueous system, such as a cooling water system, in order to inhibit corrosion as well as the deposition of corrosion within the system. The water soluble phosphino polycarboxylate may be derived from a phosphinyl unsaturated monomer and an ethylenically unsaturated carboxylic acid monomer. The aqueous system may be a cooling water system such as a cooling tower, a closed cooling water system, an air-conditioning water systems, a wastewater treatment system as well as a deionized water production system.

Disclosed herein are phosphoester anticorrosion compositions comprising an adduct of an alkylphenol ethoxylate phosphate ester with 1,3,5,7-tetraazaadamantane. The adducts are storage stable neat or in a solvent. The adducts are suitably added at about 0.5 ppm to 500 ppm by weight or by volume to a water source comprising one or more corrodents to inhibit corrosion of metal surfaces contacting the water source. The phosphoester anticorrosion compositions are as effective or more effective at inhibiting corrosion than conventional sulfur-based corrosion inhibitors when compared on a weight or volume basis.

A method of inhibiting corrosion of a metal surface in contact with geothermal system is provided. The method may include contacting the metal surface with a corrosion inhibitor composition by adding the composition to geothermal process water. The corrosion inhibitor composition may include an organic phosphonate, an ortho phosphate, and zinc or a salt thereof.

A surface protection composition having a compound represented by the formula (1) in an amount of 0.1 to 10 mass % in terms of phosphorus element with respect to the total amount of the composition, the compound (b) the metal-containing compound in an amount of 0.1 to 10 mass % in terms of a metal element with the total amount of the composition or the amine compound in an amount of 0.1 to 5.0 mass % in terms of nitrogen element the total amount of the composition, the compound (c) (meth)acrylate having 2 or more carbon-carbon double bonds and hydrocarbon chains having four or more carbon atoms in an amount of 1.0 to 70 mass % with the total amount of the composition, the compound (d) a photopolymerization initiator in an amount of 0.1 to 10 mass % with the total amount of the composition.

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An additive comprising tris (2-carboxyethyl) phosphine (TCEP) and/or tris (3-hyroxypropyl) phosphine (THPP) may be added to an aqueous system in an effective amount to inhibit corrosion of the metallurgy within the aqueous system, wherein the additive may be in the form of a solution and maintains its stability and effectiveness in inhibiting corrosion in a wide range of temperature, pressure, and pH conditions of the aqueous system.

An additive comprising tris (2-carboxyethyl) phosphine (TCEP) and/or tris (3-hyroxypropyl) phosphine (THPP) may be added to an aqueous system in an effective amount to inhibit corrosion of the metallurgy within the aqueous system, wherein the additive may be in the form of a solution and maintains its stability and effectiveness in inhibiting corrosion in a wide range of temperature, pressure, and pH conditions of the aqueous system.

An additive comprising one or more C.sub.3-C.sub.12 hydroxycarboxylic acids and/or one or more C.sub.3-C.sub.12 hydroxycarboxylic acid salts may be added to an aqueous system having galvanized metallurgy or a carbon steel surface in an effective amount to passivate a galvanized coating on the metallurgy or to decrease white rust formation or other types of corrosion upon the galvanized metallurgy or carbon steel surface in an aqueous system. In a non-limiting embodiment, the C.sub.3-C.sub.12 hydroxycarboxylic acid or the C.sub.3-C.sub.12 hydroxycarboxylic acid salt additive may utilize the zinc in the galvanized coating to achieve passivation. The passivation may occur while the system is shut down or in service. The aqueous system may be or include a cooling tower, a cooling water system, and combinations thereof. The additive may be used with or in the absence of a phosphorous-containing compound.

An additive comprising one or more C.sub.3-C.sub.12 hydroxycarboxylic acids and/or one or more C.sub.3-C.sub.12 hydroxycarboxylic acid salts may be added to an aqueous system having galvanized metallurgy or a carbon steel surface in an effective amount to passivate a galvanized coating on the metallurgy or to decrease white rust formation or other types of corrosion upon the galvanized metallurgy or carbon steel surface in an aqueous system. In a non-limiting embodiment, the C.sub.3-C.sub.12 hydroxycarboxylic acid or the C.sub.3-C.sub.12 hydroxycarboxylic acid salt additive may utilize the zinc in the galvanized coating to achieve passivation. The passivation may occur while the system is shut down or in service. The aqueous system may be or include a cooling tower, a cooling water system, and combinations thereof. The additive may be used with or in the absence of a phosphorous-containing compound.

The present invention relates generally to methods for forming peroxyformic acid, comprising contacting formic acid with hydrogen peroxide. The methods for forming peroxyformic acid can include adding formic acid with a relatively lower concentration of hydrogen peroxide, or adding formic acid to a peroxycarboxylic acid composition or forming composition to react with hydrogen peroxide in the compositions. The present invention also relates to peroxyformic acid formed by the above methods. The present invention further relates to the uses of peroxyformic acid for treating a variety of targets, e.g., target water, including target water used in connection with oil- and gas-field operations. The present invention further relates to methods for reducing or removing H.sub.2S or iron sulfide in the treated water source, improving clarity of the treated water source, or reducing the total dissolved oxygen or corrosion in the treated water source, using peroxyformic acid, including peroxyformic acid generated in situ.