Treatments for controlling liquid and vapor phase corrosion with film-forming compounds
AssigneeChemtreat, Inc.
InventorsDale P. STUART, Robert JEFFERS
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Abstract
Treatments are described for inhibiting corrosion in aqueous systems having metal surfaces that are in contact with water in a liquid phase and a vapor phase. The treatment includes adding a film-forming amine to the water and adding an additional film-forming compound that includes at least one of (i) an ethoxylated alkyl amine, (ii) an alkyl bis amide, and (iii) a fatty acid, an ester of the fatty acid, or an alkoxylated product of the fatty acid.
Claims20
A method of treating an aqueous system having corrodible metal surfaces that are in contact with water in a liquid phase and a vapor phase, the method comprising:
- combining with the water (a) at least one film-forming amine (“FFA”) having a primary amine group and an aliphatic hydrocarbon group having 5 to 40 carbon atoms;
- and (b) at least one additional film-forming compound selected from the group consisting of:
- (i) an ethoxylated alkyl amine having an ethoxy-substituted amine group and an aliphatic hydrocarbon group having from 5 to 40 carbon atoms, wherein the ethoxylated alkyl amine has from 1 to 25 ethoxy groups;
- (ii) an alkyl bis amide having at least two aliphatic hydrocarbon groups having 5 to 40 carbon atoms;
- and
- (iii) a fatty acid compound that includes at least one carboxylic acid group and an aliphatic hydrocarbon group having from 5 to 40 carbon atoms, an ester of the fatty acid compound, or an alkoxylated product of the fatty acid compound,
- wherein the at least one FFA and the at least one additional film-forming compound are added to the water in a relative weight ratio that is in a range of from 1:10 to 10:1.
A method of treating a boiler system that includes a boiler that generates steam by heating liquid water and operates a temperature in a range of from 100 to 500° C. and a pressure of from 100 to 4,000 psig, the method comprising:
- combining with the water (a) at least one film-forming amine (“FFA”) having a primary amine group and an aliphatic hydrocarbon group having 5 to 40 carbon atoms;
- and (b) at least one additional film-forming compound selected from the group consisting of:
- (i) an ethoxylated alkyl amine having an ethoxy-substituted amine group and an aliphatic hydrocarbon group having from 5 to 40 carbon atoms, wherein the ethoxylated alkyl amine has from 1 to 25 ethoxy groups;
- and
- (ii) an alkyl bis amide having at least two aliphatic hydrocarbon groups having 5 to 40 carbon atoms,
- wherein the FFA and the additional film-forming compound are combined with the water so that they are present in the liquid water at a combined concentration that is in a range of from 20 ppb to 20 ppm, and are added to the water at a relative weight ratio that is in a range of from 1:2 to 2:1.
A liquid composition that includes:
- (a) from 40 wt. % to 99 wt. % of water or other solvent;
- (a) from 0.1 to 10 wt. % of at least one film-forming amine (“FFA”) having a primary amine group and an aliphatic hydrocarbon group having 5 to 40 carbon atoms;
- (b) from 0.1 to 10 wt. % of an additional film-forming compound selected from the group consisting of:
- (i) an ethoxylated alkyl amine having an ethoxy-substituted amine group and an aliphatic hydrocarbon group having from 5 to 40 carbon atoms, wherein the ethoxylated alkyl amine has from 1 to 25 ethoxy groups;
- (ii) an alkyl bis amide having at least two aliphatic hydrocarbon groups having 5 to 40 carbon atoms;
- and
- (iii) a fatty acid compound that includes at least one carboxylic acid group and an aliphatic hydrocarbon group having from 5 to 40 carbon atoms.
Dependencies are inferred from the claim text.