Corrosion control for water systems using passivators and a hydroxycarboxylic acid
AssigneeChemtreat, Inc.
InventorsRajendra Prasad Kalakodimi, Santanu Banerjee, Patrick Wood, Deann C. Guy, Curt Turner
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Abstract
Methods and compositions for suppressing corrosion of a corrodible metal surface that contacts a water stream in a water system. The method comprises introducing into the water stream a treatment composition, the treatment composition including a combination of passivators and a hydroxycarboxylic acid promoter.
Claims16
A method of suppressing corrosion of a corrodible metal surface that contacts a water stream in a water system, the method comprising:
- introducing into the water stream a treatment composition including (i) a combination of passivators that include at least two multivalent salts selected from the group consisting of manganese, tungstate, aluminum, and tin, and (ii) a hydroxycarboxylic acid promoter, the hydroxycarboxylic acid promoter having a carboxylic acid group and a hydroxyl group that is bonded to a carbon atom that is adjacent to the carboxylic acid group,
- wherein the treatment composition is introduced so that (i) the concentration of the combination of the passivators in the water stream is in the range of 0.1 to 10 ppm, (ii) the concentration of the promoter in the water stream is in the range of 2 ppm to 50 ppm, and (iii) the ratio of the concentration of the combination of the passivators to the concentration of the promoter is in a the range of from 0.01 to 0.4.
A method of suppressing corrosion of a corrodible metal surface that contacts a water stream in a water system, the method comprising:
- introducing into the water stream a treatment composition including (i) a combination of salts of multi valent metals a tin salt and an aluminum salt and (ii) a hydroxycarboxylic acid promoter, the hydroxycarboxylic acid promoter having a carboxylic acid group and a hydroxyl group that is bonded to a carbon atom that is adjacent to the carboxylic acid group, promoter that is selected from the group consisting of tartaric acid, glucaric acid, glucoheptonate, and gluconic acid,
- wherein the treatment composition is introduced so that (i) the concentration of the combination of the tin salt and the aluminum salt in the water stream is in the range of 0.1 to 10 ppm, (ii) the concentration of the promoter in the water stream is in the range of 2 ppm to 50 ppm, (iii) the ratio of the concentration of the tin salt in the water stream to the concentration of the promoter in the water stream is in the range of from 0.01 to 0.4, and (iv) the ratio of the concentration of the aluminum salt in the water stream to the concentration of the promoter is in a the range of from 0.01 to 0.4.
Dependencies are inferred from the claim text.