%0 Journal Article
%T Inhibition Effect of Substituted Thiadiazoles on Corrosion Activity of N80 Steel in HCl Solution
%A M. Yadav
%A Sumit Kumar
%A Debasis Behera
%J Journal of Metallurgy
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/256403
%X The inhibition effect of some prepared compounds, namely, thiadiazole derivatives, on N80 steel corrosion in 15% HCl solutions has been studied by using the weight loss, electrochemical polarization, and electrochemical impedance spectroscopy techniques. It was found that the inhibition efficiency of the thiadiazole derivatives, namely, 2-amino-5-(4-methoxyphenyl)-1,3,4-thiazole (AMPT), 2-amino-5-phenyl-1,3,4-thiazole (APT), and 2-amino-5-(4-chlorophenyl)-1,3,4-thiazole (ACPT), increases with the increase in concentration. Inhibition efficiency follows the order AMPT > APT > ACPT. The effect of temperature on the corrosion was investigated by the weight loss method, and some thermodynamic parameters were calculated. The inhibitive action may be attributed to the adsorption of inhibitor molecules on the active sites of the metal surface following Langmuir adsorption isotherm. Polarization measurements indicated that thiadiazole derivatives act as mixed-type corrosion inhibitor. The adsorption of thiadiazole derivatives on N80 surface exposed to inhibitor-containing solutions was confirmed using SEM and FT-IR spectra. 1. Introduction N80 carbon steel has been generally used as the main construction material for down hole tubular, flow lines, and transmission pipelines in petroleum industry. In most industrial processes, acidic solutions are commonly used for pickling, industrial acid cleaning, acid descaling, oil well acidifying, and so forth [1¨C5]. It is commonly noticed that 15¨C28% of hydrochloric acid is used for the acidization of petroleum oil wells [6, 7]. Because of their aggressiveness, iron and its alloys get corrodes during these acidic applications particularly with the use of hydrochloric acid and sulphuric acid, which results in terrible waste of both resources and money [8]. Addition of inhibitor remains the necessary procedure to secure the metal against acid attack. Therefore, corrosion inhibitors for HCl solutions have attracted more attention. Most of the well-known corrosion inhibitors are organic compounds containing polar groups having nitrogen, sulphur, and/or oxygen atoms and heterocyclic compounds with polar functional groups and conjugated double bonds [9, 10]. These compounds can adsorb on the metal surface and partially blocking the active sites on the surface, thereby reducing the corrosion rate. Among different nitrogen- and sulphur-containing compounds, thiosemicarbazide has been reported to be a potential inhibitor for different metals [11, 12]. Most of the investigation is related to the application of common inhibitors
%U http://www.hindawi.com/journals/jm/2013/256403/