Inhibitive effect of<i> Irvingia Gabonensis</i> leaf extract on the corrosion of mild steel in 1.0m hydrochloric acid

Abstract

This investigation utilizes leaf extracts as corrosion inhibitors and studies the inhibitive effect of Irvingia gabonensis leafextracton mild steel immersed in 1.0M HCl acid at ambient conditions. The phytochemical constituents responsible for the corrosion inhibition were determined by standard phytochemical methods. The chemicals detected were alkaloids, flavonoids, saponins, and tanins. The study was carried out using eleven (11) experimental setups, which consisted of: 1.0M HCl (control 1), 10ml, 15ml, 20ml, and 25ml extracts in 1.0M HCl and distilled water (control 2). The experiment was conducted using the weight loss/corrosion rate measurement technique and the results showed that the extract concentration and exposure time had effects on the corrosion rate, whilst the 25ml extract inhibited the most in the acidic medium.The results of the experiment with the two-factor ANOVA without replication indicated that the extract concentration had a more significant effect on corrosion rate than the exposure time. Having this in mind, the inhibitive effect of Irvingnia gabonensis (Africa mango or ogbono) leaf extract as an organic "green" inhibitor on mild steel corrosion in an acidic medium can be said to depend on the concentration of the extract for better effectiveness and inhibition efficiency. Therefore, Irvingia gabonensis leaf extract, with an inhibition efficiency of 67.14% on mild steel in a moderate acidic environment, can be recommended for use in commercial and industrial environments where mild steel material is required in service.