Investigative Study Of Adansonia Digitata (Baobab) Extracts As Green Corrosion Inhibitor Of Mild Steels And 2101 Duplex Stainless Steel In Acid Medium
Abstract
In spite of the advanced utilization of mild steel and dual phase stainless steel due to their amenability to heat treatment and alloying, corrosion remains a point of concern to their applications. The use of natural inhibitors has been a proffered solution to corrosion challenges in engineering materials. In view of this, the work focused on investigating the inhibitive properties of Baobab (leaf, bark and the root) plant extract on Mild Steel (MS) and 2101 Duplex Stainless Steel (DSS2101) in H2SO4 solution. The FTIR result shows the hydroxyl (O-H), amide (N-H), aromatic alkene (C-C) and sulfano (S=O) groups stretching mode which are the functional group of organic anti corrosion agent saponin, tannins, steroid and flavonoids. The polarization studies show the effect of inhibitors concentration increase on the corrosion inhibition efficiency. The root exhibited highest corrosion inhibitor efficiency (75.63%) on Mild Steel at 300 ppm and (31.14%) on Mild Steel with root extract in 300ppm. There was also a reduction in the corrosion current (Icorr) value as the extract concentration increases. In addition, the isotherm adsorption behaviour of Baobab (leaf, bark and the root) plant extract on MS and 2101DSS surface is known with Langmuir isotherm adsorption and involves physical adsorption. This confirms the inhibitive effect of the leaf, root and bark extracts, in the sulphuric acid medium.
