Ethanol extract of corn husk for mild steel corrosion prevention in saline water

Abstract

Natural materials are used for corrosion prevention of metals due to their low cost, zero noxiousness, biomolecules, and effectiveness. However, natural materials are very less used for corrosion prevention as coating materials. In the present report, the ethanol extract of corn husk (EECH) is investigated as natural, low cost and effective coating material for mild steel (MS) protection in chloride (0.5 M NaCl) solutions. Characterization of EECH is performed by UV–visible (UVS) spectroscopy, which suggests that the EECH is chemically active. EECH layers (L) are coated on MS by drop casting. Corrosion testing of MS and EECH coated MS is done in 0.5 M NaCl by electrochemical impedance spectroscopy (EIS), open circuit potential (OCP) curves, and Tafel polarization curves (TPC). It is declared after analysis of the results that EECH prevention ability enhances with the count of layers and 3 L coated MS has given the best protection (77 %) among the tested ones. Surface morphology is analyzed by optical microscopy (OM) and Field emission Scanning electron microscopy (FESEM), which supports that EECH coated MS is less damaged in NaCl than alone MS. It is concluded based on this work that EECH can effectively suppress MS corrosion in 0.5 M NaCl.