Corrosion inhibition of copper by pyrazole pyrimidine derivative in synthetic seawater: Experimental and theoretical studies

The present study focuses on the inhibitive action of 1H, 4H, 5H-pyrazolo[3,4-d]pyrimidine (PPO) as corrosion inhibitor for copper in 3% NaCl solution by electrochemical techniques and gravimetric method. Results indicated that the compound under study exhibited good inhibition activity with a maximum value of 96.5% at 10(-3)M. The compound was classified as a mixed type inhibitor with an anodic predominance. The protection efficiency was enhanced with increasing the inhibitor concentration and decreased with the increment of temperature. The adsorption of the inhibitor occurred spontaneously and obeyed to Langmuir isotherm. Monte Carlo simulations showed that PPO had a high adsorption energy and possessed the ability to replace pre-adsorbed aggressive species on copper surface and then formed a protective film. PPO was adsorbed in a parallel configuration providing better coverage of the metal surface. (C) 2020 Elsevier Ltd. All rights reserved.