Starch as an ecofriendly green inhibitor for corrosion control of 6061-Al alloy

The corrosion inhibition characteristics of biopolymer starch was studied as an ecofriendly inhibitor for the corrosion control of 6061 aluminum alloy in 0.1M HCl. Electrochemical methods such as potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) techniques were adopted. Effect of inhibitor concentrations (in the range of 100 to 800ppm) was studied at temperatures of 30, 35, 40, 45 and 50?. The kinetic and thermodynamic parameters for corrosion and inhibition process were determined. The surface morphology of aluminum in the absence and presence of starch in 0.1M HClsolution was studied using Scanning Electron Microscope (SEM) and Electron Dispersive x-ray spectroscopy (EDX). Suitable mechanism was proposed for corrosion and inhibition process. The percentage inhibition efficiency of starch increased with increasing inhibitor concentrations and also with increase in temperature. Starch acted as a mixed inhibitor, underwent chemical adsorptionand obeyed Langmuir adsorption isotherm.Starch - a biodegradable polymer emerged as a potential, cost effective environmentally begin inhibitor for the corrosion control of 6061-aluminum inHCl.