Author/Authors :
Faydy, Mohamed El Laboratory of Agro-Resources - Polymers and Process Engineering - Department of Chemistry - Faculty of Science - Ibn Tofail University, Morocco , Galai, Mouhsine Laboratory of Materials Engineering and Environment: Modeling and Application - Faculty of Science - Ibn Tofail University, Morocco , Rbaa, Mohamed Laboratory of Agro-Resources - Polymers and Process Engineering - Department of Chemistry - Faculty of Science - Ibn Tofail University, Morocco , Ouakki, Moussa Laboratory of Materials - Electrochemistry and Environment - Faculty of Science - Ibn Tofail University, Morocco , Lakhrissi, Brahim Laboratory of Materials Engineering and Environment: Modeling and Application - Faculty of Science - Ibn Tofail University, Morocco , Touhami, Mohamed Ebn Laboratory of Materials Engineering and Environment: Modeling and Application - Faculty of Science - Ibn Tofail University, Morocco , Kacimi, Younes El Laboratory of Materials Engineering and Environment: Modeling and Application - Faculty of Science - Ibn Tofail University, Morocco
Abstract :
New quinoline, namely 5-penthylaminomethyl-8-hydroxyquinoline (P-QN) has been synthesized and characterized by different spectral methods such as 1H NMR and 13C NMR. Their inhibitive action against the corrosion of carbon steel in 1.0 M hydrochloric acid solution were investigated at different temperatures in the range from 25±2 to 55±2 °C by a series of known techniques such weight loss, electrochemical impedance spectroscopy (EIS) and Tafel polarization measurements. The obtained results show that compound (P-QN) is a very good inhibitor with efficiency of 93.3% at 10-3 M additive concentration in 1.0 M HCl solution. Generally the inhibition efficiency increased with increase of inhibitor concentration. Changes in impedance parameters (Rct and Cdl) were indicative of adsorption of compound (P-QN) on the metal surface, leading to the formation of a protective film. Tafel polarization measurements showed that the inhibitor (P-QN) is a mixed type. The adsorption of the inhibitor on the surface of carbon steel in 1.0 M HCl solution was found to obey Longmuir’s adsorption isotherm. The kinetic and thermodynamic parameters for carbon steel corrosion and inhibitor adsorption, respectively, were determined and discussed. On the bases of thermodynamic adsorption parameters, comprehensive adsorption (physisorption and chemisorption) for the studied inhibitors on carbon steel surface was suggested.
Keywords :
Quinoline derivatives , Corrosion inhibition , Carbon steel , Hydrochloric Acid , EIS
