Study of jojoba vegetable oil as inhibitor of carbon steel C38 corrosion in different acidic media

This work reports the use of a new kind of metal corrosion inhibitors called green inhibitors. the aim of this study is the evaluation of inhibitor efficiency of an oil extracted from the jojoba plant against the corrosion of c38 carbon steel in hcl (1m),h3po4 (0.5 m) and h2so4 (0.5m) media,using mass loss measurement and electrochemical methods. gravimetric and electrochemical studies show that the addition of jojoba oil in the three media causes a decrease in corrosion current density and therefore a decrease in the rate of corrosion of steel c38. the inhibitor efficiency of the oil increases with the increase in the concentration of inhibitor. the highest efficiency of the employed inhibitor is found at 3 g/l concentration. jojoba oil acts as a mixed inhibitor in hcl(1m) medium. in h3po4 (0.5 m) and h2so4 (0.5 m) media,the inhibitor is anodic. its efficiency is optimum in 1m hcl medium instead in h2so4 0.5m. this is probably because the so42- ions adsorb with higher rate than the cl- ions on the metallic surface,thus occupying more active sites on the surface and leaving enable fewer sites.