Green synthesis of Terminalia Glaucescens Planch (Udi plant roots) extracts as green inhibitor for aluminum (6063) alloy in acidic and marine environment

Abstract

Green synthesis of Terminalia Glaucescens Planch extracts for potential application as green inhibitor for aluminum (6063) alloy immersed in acidic (0.3 M H2SO4) and marine (3.5% NaCl) solution respectively was investigated. The phytochemical examination of the extract was conducted to confirm its bioactive constituents while the inhibition potential of the extract at varied concentration on corrosion of Al (6063) alloy in acid and salt solutions was evaluated using potentiodynamic polarization studies and electrochemical impedance spectroscopy respectively (EIS). Scanning electron microscopy (SEM) was used to examine the morphology of the alloy in the absence and presence of inhibitor while FT-IR was used to determine functional group present in the inhibitor extract. The results showed considerable amount of bioactive agents such as Flavanoids, Tannis and Keller killani present in the Terminalia Glaucescens Planch extracts which is indication of its inhibition potential. The corrosion rates obtained from the polarization curves indicate significant decrease as the concentration of the extracts increases both in acid and salt solutions which is in agreement with the EIS measurements. The surface morphology of the uninhibited alloys in acid and salt showed more pronounced deterioration due to aggressive attack from corrosive media unlike the inhibited alloys.