Corrosion inhibitor formulations for use in heat transfer fluids include: (a) an optionally substituted benzoic acid or a salt thereof; (b) at least a first n-alkyl monocarboxylic acid or a salt thereof and a second n-alkyl monocarboxylic acid or a salt thereof, the first n-alkyl monocarboxylic acid and the second n-alkyl monocarboxylic acid being different; and (c) an azole compound. A ratio of weight percent of the first n-alkyl monocarboxylic acid or the salt thereof to weight percent of the second n-alkyl monocarboxylic acid or the salt thereof ranges from about 1:0.75 to about 1:2.00. A ratio of weight percent of the benzoic acid or the salt thereof to combined weight percent of the first n-alkyl monocarboxylic acid or the salt thereof and the second n-alkyl monocarboxylic acid or the salt thereof ranges from about 1:0.30 to about 1:2.25.

Disclosed herein is an aqueous composition having a pH value at 55° C. in the range from 5 to 9, containing at least two different amino organophosphonic acid derivatives of formula (I)

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where residues R independently of each other are CH.sub.2—PO(OR″).sub.2, residues R′ independently of each other are alkylene residues with 2 to 4 carbon atoms, residues R″ independently of each other are H, Na, K, Li or NH.sub.4; and n is an integer from 0 to 4; and where the at least two different amino organophosphonic acid derivatives differ in the value of n. Further disclosed herein is a concentrate to produce such compositions, a pickling method for pickling metallic substrates making use of the compositions, a coating method for coating metallic substrates including the pickling method and a method of using the compositions for pickling metallic substrates.

Corrosion inhibitor compositions are provided that can include a mixture of one or more alkaline earth metals, one or more organic phosphates, one or more inorganic phosphates, optionally a dispersant, and hydroxyphosphono acetic acid and/or salts thereof and/or derivatives of hydroxyphosphono acetic acid and/or salts thereof. Methods of mitigating or inhibiting corrosion of metal surfaces are also disclosed. The methods can include the steps of adding a corrosion inhibitor composition as described in the present disclosure to a medium in contact with the metal surface and optionally to the metal surface before it is contacted by the medium.

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.

Methods and compositions for inhibiting corrosion of metal surfaces in aggressive fluids, including fluids with high total dissolved solids content. The treatment composition can include a stannous corrosion inhibitor and optionally an additive that enhances the corrosion inhibition properties of the stannous component. The additive may include organic compounds having at least one heteroatom.

Corrosion inhibitor formulations for use in heat transfer fluids include: (a) an optionally substituted benzoic acid or a salt thereof; (b) at least a first n-alkyl monocarboxylic acid or a salt thereof and a second n-alkyl monocarboxylic acid or a salt thereof, the first n-alkyl monocarboxylic acid and the second n-alkyl monocarboxylic acid being different; and (c) an azole compound. A ratio of weight percent of the first n-alkyl monocarboxylic acid or the salt thereof to weight percent of the second n-alkyl monocarboxylic acid or the salt thereof ranges from about 1:0.75 to about 1:2.00. A ratio of weight percent of the benzoic acid or the salt thereof to combined weight percent of the first n-alkyl monocarboxylic acid or the salt thereof and the second n-alkyl monocarboxylic acid or the salt thereof ranges from about 1:0.30 to about 1:2.25.

A composition and method of inhibiting corrosion and white rust on metal components in a water system. The composition preferably comprises an amino-acid based polymer (most preferably a polyaspartic acid or a salt thereof), hydroxyphosphonoacetic acid, and a second phosphonic acid (preferably a phosphonocarboxylic acid), and does not require the use of regulated metals. The composition is effective even in the presence of biocides. A preferred method of inhibiting white rust comprises adding an amino-acid based polymer or hydroxyphosphonoacetic acid or both to the water system. A preferred method of inhibiting corrosion or white rust comprises adding an amino-acid based polymer, hydroxyphosphonoacetic acid, and a phosphonocarboxylic acid to the water system. Preferably the active concentrations are at least 3 ppm each of the amino-acid based polymer and hydroxyphosphonoacetic acid when added to a volume of water in the water system.

A method for manufacturing a ruthenium wiring including (i) treating a metal surface including ruthenium using a first chemical solution including a compound having a functional group capable of coordinating to a ruthenium atom, and (ii) carrying out an etching treatment on the metal surface including ruthenium treated with the first chemical solution, using a second chemical solution.

A composition and method of inhibiting corrosion, white rust, and scale formation on components in a water system. The composition preferably comprises an amino-acid based polymer (most preferably a polyaspartic acid or a salt thereof), hydroxyphosphonoacetic acid, and a second phosphonic acid (preferably a phosphonocarboxylic acid), and does not require the use of regulated metals. The composition is effective even in the presence of biocides. A preferred method of inhibiting white rust comprises adding an amino-acid based polymer or hydroxyphosphonoacetic acid or both to the water system. A preferred method of inhibiting corrosion, white rust, and scale formation comprises adding an amino-acid based polymer, hydroxyphosphonoacetic acid, and a phosphonocarboxylic acid to the water system. Preferably the active concentrations are at least 3 ppm each of the amino-acid based polymer and hydroxyphosphonoacetic acid when added to a volume of water in the water system.

Certain metal surfaces are often unable to be effectively contacted with fluids containing hydrofluoric acid due to significant corrosion issues. Titanium and titanium alloy surfaces represent but one example. Corrosion inhibitor compositions comprising boric acid and an N-(phosphonoalkyl)iminodiacetic acid or any salt thereof can be used to suppress metal corrosion, including that taking place on titanium and titanium alloy surfaces. Methods for suppressing corrosion of a metal surface can comprise: contacting a metal surface with a corrosive environment, the metal surface comprising titanium or a titanium alloy and the corrosive environment comprising hydrofluoric acid; introducing a corrosion inhibitor composition to the corrosive environment, the corrosion inhibitor composition comprising boric acid and an N-(phosphonoalkyl)iminodiacetic acid or any salt thereof; contacting the metal surface with the corrosion inhibitor composition; and allowing the corrosion inhibitor composition to suppress corrosion of the metal surface by the corrosive environment.