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US 5,314,660 AGranted
Use of cationic alkyl-phosphonium salts as corrosion inhibitors in open recirculating systems
AssigneeGrace Dearborn Inc.
InventorsBrian E. Clark, Ronald L. Oleka
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Abstract
A method for inhibiting corrosion of metals which are in contact with an aqueous system comprising adding to the system, either alone or in combination with organic or metal containing water treatments, a water-soluble cationic alkyl-phosphonium salt in an amount effective to inhibit corrosion.
Claims10
A method for inhibiting corrosion of metals which are in contact with an aqueous system which comprises adding to the system, in a dosage range between 0.1 ppm to 500 ppm, a water soluble, cationic alkyl phosphonium salt having the formula:
- ##STR3## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are each independently selected from the group consisting of C.sub.1 to C.sub.18 alkyl, C.sub.5 to C.sub.7 cycloalkyl or aryl, and wherein X is an anion selected from the group consisting of halide, alkosulfate, tosylate, carboxylate, sulfonate, sulfate, phosphate, phosphonate, acetate, or nitrate;
- monitoring the corrosion rate of the metals in the system, and if the corrosion rate is unacceptable, modifying the dosage of the cationic alkyl phosphonium salt to a dosage which effectively inhibits corrosion of the metals.
Dependencies are inferred from the claim text.