Protection of corrosion of carbon steel by inhibitors in chloride containing solutions

Protection of corrosion of carbon steel by inhibitors in chloride containing solutions

In the first part of this study, the inhibitor effect of single, binary and ternary mixture of chromate, molybdate, nitrite, tetraborate, ortophosphate, benzoate, acetate, ascorbic acid on the corrosion of carbon steel was investigated. Experiments were carried out in neutral aqueous solution containing 100 ppm $Cl^-$ at room temperature. The current-potential curves were obtained by potentiostatic (1mV/s) method and the corrosion rates were determined by the extrapolation of the Tafel slope of the cathodic polarization curves method and linear polarization method. In the second part, the inhibitor effect of some one component, binary and ternary inhibitor blends was investigated depending on the temperature (30, 40, 50 °C) and pH (5, 7, 9). The inhibitor effects were found to be %95 for solutions containing 50 ppm nitrite. Of all inhibitor systems tried, chromate-molibdate and chromate- nitrite- molibdate was found to be the most effective binary and ternary inhibitor blends, the effectiveness of which is equal to that of sodium chromate, sodium nitrite, sodium molibdate that alone and used at a high level.

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