A method for korrosionsbekaempfung in aqueous systems, therefor suitable composition and their use

摘要

A method of inhibiting corrosion in an aqueous system comprises adding to the system a water soluble inorganic nitrite and an organic phosphonate which contains at least one carboxylic acid group and at least one phosphonic acid group the said two acid groups being attached to carbon atoms, the concentration of phosphonate exceeding 5 ppm weight per volume and the weight ratio of nitrite to phosphonate being from 90:10 to 5:95.