Journal of the Tunisian Chemical Society, 2017, 19, 43-51 43 * Corresponding author, e-mail address : nasr.khawla@gmail.com S235JR steel corrosion behavior in neutral chloride media Khaoula Nasr a* , Michele Fedel b , Flavio Deflorian b , Nizar Bellakhal c , Nébil Souissi a a University of Tunis El Manar, Institut Préparatoire aux Etudes d’Ingénieurs d’El Manar, BP 244 El Manar II, 2092 el Manar, Tunisia. b University of Trento, Department of industrial engineering, Via Mesiano 77, 38123 Trento, Italy. c University of Carthage, Institut National des Sciences Appliquées et Technologie, 1080 Tunis Cedex, Tunisia. (Received: 24 May 2016, accepted: 02 July 2016) Abstract: We investigated the electrochemical behavior of S235JR steel in chloride media. The results of studying the effect of chloride concentration were reported and compared to those obtained for ordinary carbon steel (OS). Potentiodynamic polarization and cyclic voltammetry techniques were employed. For S235JR steel, it was revealed that the corrosion rate increased at higher chloride concentration and a first order kinetics was obtained. The pitting potential varied linearly with the logarithm of chloride concentration and the slope value was 110.9 mV/decade. In comparison with the ordinary carbon steel corrosion behavior, S235JR steel showed generally a better general corrosion resistance in chloride media. This was reflected by a lower value of corrosion current density equal to 8.6 mA cm -2 compared to OS (28.3 mA cm -2 ). The pitting potential determined for S235JR steel (-336 mV/SCE) was more positive than the one of OS (-365 mV/SCE) highlighting that S235JR steel is less subjected to pitting corrosion. Keywords: S235JR steel, chloride, pitting, polarization, voltammetry. INTRODUCTION With the rapid development of petroleum industry, tanks play an increasing role in oil and derivatives storage. These tanks are exploited in an open park which is mostly situated in a marine environment. Thus, materials surfaces are subjected to severe corrosion. To prevent environmental disasters and minimize activities disruption, it is important to find reliable methods for materials preservation. This is possible only when understanding the corrosion mechanism evolved. Hydrocarbon storage tanks are made of carbon steel due to its excellent mechanical properties and its low cost. Several investigations have been concerned on discovering its corrosion mechanism in neutral media containing chloride ions [1]. Although S235JR carbon steel is used as a building material for hydrocarbon storage tanks, there is a lack of studies dealing with its corrosion phenomenon in chloride media. In fact, Trzaska and al. [2] compared the electrochemical behavior of pure iron and S235JR steel in NaCl 0.5M solution employing potentiodynamic and impedance spectroscopy techniques. The authors reported a lower corrosion resistance of S235JR steel due to alloying elements addition and material heterogeneity. Popescu and al. [3] also aimed to study the corrosion of S235JR steel and austenitic 304 stainless steel in both HCl 0.5 M and NaCl 3% media by potentiodynamic technique. The results confirmed that regardless of the corrosive solution, S235JR steel corrosion rate was higher. In the other hand, hydrochloric acid medium was much more aggressive to S235JR steel than sodium chloride solution. The purpose of this paper is to extend our knowledge on S235JR steel corrosion in neutral aerated chloride media. The effect of chloride anions concentration on cyclic voltammetry and polarization investigations responses was evaluated. EXPERIMENTAL The specimens under investigation were S235JR steel and ordinary carbon steel (OS)