Inhibiting Effects of Some Bis-azoles Compounds on Corrosion of Copper in HCl Solution
M. Sobhi *
Department of Chemistry, Faculty of Science, Benha University, Benha, Qalubya, Egypt and Department of Chemistry, Faculty of Science, University of Tabuk, Tabuk, Saudi Arabia
*Author to whom correspondence should be addressed.
Abstract
The inhibition effect of three bis- azole derivatives, namely bis-[5-hydroxy-1, 3, 4- oxadiazol-2-yl] methane, bis-[5-chloro-1, 3, 4- oxadiazol-2-yl] methane and bis-[5-thiol-1, 3, 4- oxadiazol-2-yl] methane have been investigated against the copper corrosion in 1.0 M HCl solution. The corrosion parameters were calculated using weight loss, potentiodynamic polarization, cyclic voltammetry and electrochemical impedance techniques. Potentiodynamic and cyclic voltammetric measurements indicate that the studied bis- azole compounds are mixed type inhibitors. The best inhibition efficiency was observed from the hydroxy derivative is 96.34% at 1x10-3M. The adsorption of the investigated compounds was found to obey the Langmuir isotherm model. Also the mechanism of inhibition was discussed in view of the conductometric titration analysis.
Keywords: Bis-azole derivatives, copper, corrosion inhibitor