Electrochemical behavior of carbon steel under a continuous kerosene flow in two different kind of sections

Abstract

This work studies the electrochemical behavior of carbon steel under a continuous kerosene flow in two different kinds of sections: a linear section and a 90-degree horizontal elbow section. To apply the electrochemical techniques, two experimental arrangements were designed, one with the electrochemical cell in a linear section and the other with the cell in an elbow. The electrochemical techniques used were polarization curves and electrochemical impedance spectroscopy (EIS). The polarization curves obtained indicated that the values of Icorr, as well as the density of current, increased significantly for the cell placed in the elbow section. Corrosion velocity values show that there is a difference between the experimental arrangements. The EIS technique shows that for the arrangement with the cell in an elbow, the resistance of steel to corrosion is lower than for the arrangement with the cell in a linear section. The presence of kerosene in steel modifies the corrosion process and avoids the formation and growth of a passive layer, in which the corrosive agents adsorption increases. Analysis with XPS showed that the system with the cell in a 90-degree horizontal elbow section increases crystal deposits of chloride ions on the metal surface.

Galvanic Coupling of Copper and Carbon Steel in the Presence of Bentonite Clay and Chloride

“…Contributions from the oxide film and pores were captured by R film and R pore . Inductive behaviour observed at very low frequencies in some plots is attributed to adsorbed intermediate species, as frequently observed on steel surfaces, 31,32 and was modelled though the inclusion of inductance L and/or associated resistance R L .…”