Compositions and methods for inhibiting corrosion in aqueous media
AssigneeGeneral Electric Company
InventorsRosa Crovetto, Claudia C. Pierce, Philip D. Deck
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Abstract
Methods and compositions are provided for corrosion inhibition treatment of aqueous systems such as cooling water systems. The methods include conjoint use of a polyvalent metal ion, such as Al or Mn and a corrosion inhibitor/deposit control agent (DCA) to the water system. The corrosion inhibitor DCA agent may be an organic compound such as a hydroxyacid, phosphonocarboxylic acid, polyhydroxysuccinic acid, or polymaleic acid or anhydride.
Claims16
In a water system having a total amount of from about 0.1-1.0 ppm of orthophosphate therein, an improved corrosion inhibition method comprising adding to said system:
- a) from about 0.3-0.5 ppm of a polyvalent metal ion selected from Al and Mn;
- and
- b) polymaleic acid or anhydride in an amount of about 1-25 ppm, said polymaleic acid or anhydride being water based.
A method for inhibiting the corrosion of metals in contact with an aqueous system comprising adding to said aqueous system a) from about 0.1-1.0 ppm of a polyvalent metal ion selected from the group of Al and Mn, and b) from about 1 to less than 50 ppm of a corrosion inhibitor compound selected from the group consisting of saccharic acid, polyepoxysuccinic acid, ammonia hydroxysuccinic acid, p-xylene hydroxysuccinic acid, phosphono-carboxylic acid/phosphonosuccinic acid mixture, phosphonosuccinic oliglomer, and water based polymaleic acid or polymaleic anhydride.
Dependencies are inferred from the claim text.