Chromoleana odorata and Hevea brasilensis as a Green Corrosion Inhibitor for Aluminium in Acid Solution

Abstract

The methanolic leaf extracts of Chromoleana odorata and Hevea brasiliensis were tested for corrosion inhibitory effects towards aluminum by varying the concentration of hydrochloric acid as 0.01M, 0.05M and 0.1M HCl. The anti corrosion efficiency of the plant extract was studied by means of weight loss method. It was observed from the experiment, that in the absence of the plant extracts, the weight loss increases indicating an increase in corrosion. Conversely when the plant extracts were introduced, there were remarkable decrease in weight loss leading to reduction in corrosion and an increase in inhibitory efficiency. Upon comparative analysis on the inhibitory efficiency of the two extracts, it was discovered that Chromoleana odorata gave the higher inhibition efficiency of 62% than the Hevea brasiliensis which gave 57% inhibition efficiency. This study shows that Chromoleana odorata gave better inhibition against corrosion to aluminium than Hevea brasiliensis. FT-IR spectra of the plant extracts were also examined to elucidate the possible functional groups that may be responsible for the anti-corrosion activity of these bio-degradable extracts in methanolic solution.