Electrochemical Investigation of the Adsorptive and Inhibitive Effects of Halide Ions and Anacardium occidentale Extracts on Mild Steel Corrosion in 1 M Sulphuric Acid

Abstract

By utilizing electrochemical technique, the corrosion inhibition efficiency of Anacardium occidentale leave extracts on Grade 304 austenitic mild steel in 1 M sulphuric acid solution was examined. The crude extract of Anacardium occidentale leaves was used in this study to screened the phytochemicals and examine its inhibitory qualities as a corrosion inhibitor for mild steel in 1M sulphuric acid media. The phytochemicals showed the existence of many phytochemicals were flavonoids and alkaloid provide the majority.The efficacy of Anacardium occidentale leave extracts inhibition increased with concentration while decreasing with temperature. At 0.7 g/L extract concentration for 3 hours of immersion, the inhibitor's greatest efficiency was 94%. Mild steel corrosion was successfully inhibited by Anacardium occidentale leave extracts, according to the results obtained, and it was discovered that the presence of halide ions enhanced the efficacy of the inhibition. The synergistic effect of halide ions was found to follow the order: KI >KBr>KCl. According to the electron impedence spectroscopy (EIS), Anacardium occidentale functions as a mixed-type inhibitor. Due to the extract components' adsorption on the mild steel surface, leave extracts exhibit an inhibitory effect. The activation energy of the corrosion reaction increases by the presence of both extract and halide ion. The results of a study using scanning electron microscopy to examine the surface morphology of mild steel in inhibited and uninhibited acid solutions revealed that the presence of extract and halide inhibitors remarkably lowers the corrosion rate.