<i>Carpobrotus edulis</i> leaf extract as green corrosion bio-inhibitor for copper in 3.5% NaCl solution
Mohammad Mahdi Alemnezhad, Ali Ghaffarinejad, Faezeh Omidali
Abstract
In this study, Carpobrotus edulis leaf extract (CELE) has been introduced as a new, eco-friendly, and green inhibitor of copper decomposition in a 3.5 wt.% sodium chloride solution. The water/ethanol extract of the leaves was used to investigate the chemical composition of CELE by the use of liquid chromatography combined with a mass spectrometry detector. Using polarization and electrochemical impedance spectroscopy, the dissolution rate of the copper samples in the presence and absence of various concentrations of CELE (2.5–20 wt.%) were studied, which the best being 20% with an inhibition efficiency of 87%. To evaluate the copper surface morphology and perform surface elemental analysis, scanning electron microscopy and energy dispersive spectroscopy were used. Also, the effect of temperature increment on IE% at the optimum concentration of CELE has been studied, which at 338 K was 57%. Isotherm studies showed that the CELE adsorption mechanism follows the Langmuir isotherm.