A comparative pitting corrosion study of mild steel in different alkaline solutions containing salts with sulphur-containing anions

Abstract

The localized corrosion of mild steel in alkaline solutions containing a salt with a sulphurcontaining anion (sodium sulphate, sodium sulphite, sodium thiosulphate, potassium thiocyanate and sodium sulphide) is studied by using potentiostatic and potentiodynamic techniques complemented with scanning electron microscopy. Alkaline solutions containing one of those salts produce pitting of mild steel at potential values more positive than those of the active-passive transition of iron in base. In the presence of either thiocyanate or thiosulphate anion iron pitting takes place through sulphide formation which reacts at the electrode surface yielding poorly protective ferrous sulphide. At potential more positive than the breakdown potential the kinetic behaviour fits a competitive surface reaction mechanism involving the formation of the passive film and the nucleation and growth of a ferrous sulphide salt layer. The proposed reaction model reproduces the corresponding experimental current-transients.

Novel Corrosion Inhibitor for Mild Steel in Simulated Concrete Pore Solution with Chloride Contamination

“…Similar studies were reported [5][6][7][8][9][10][11][12][13][14][15][16][17] for mid steel corrosion in chloride contaminated alkaline medium by electrochemical studies and the inhibitors repassivated the steel surface and reduce the pitting corrosion. The present work is also focused on the evaluation of corrosion resistance performance novel inhibitor for mild steel corrosion in chloride contaminated alkaline solution.…”

Surface characterization of sulfur and alkanethiol self-assembled monolayers on Au(111)

“…S-metal interactions are extremely important because S is a poison for many heterogeneous reactions involving different metallic catalysts [27,[48][49][50][51] in some technological processes of great economical interest. In fact, S layers can be formed on metal surfaces as an undesired result of the adsorption and reaction of different compounds, such as SO 2 , disulfides, alkanethiols, thiosulfates, thiocyanates, and sulfides [52,53]. Also, recently it has been found that oxide-supported metallic nanoparticles have excellent catalytic properties [54,55], an issue nowadays of great concern for future technological developments.…”

The Pitting Corrosion of Nickel in Different Electrolyte Solutions Containing Chloride Ions

“…The corrosion process is studied using electrochemical techniques complemented with scanning electron microscopy. Pit initiation of nickel in the various systems investigated can be interpreted through the same complex mechanism already applied to the pitting corrosion of iron (12).…”