Protection of mild steel from corrosion using methanol extract of avocado (Persea americana mill) seeds in a solution of sulfuric acid

Avocado seeds have been studied for use as corrosion inhibitors of mild steel in a solution of 0.75 M sulfuric acid. Corrosion inhibition efficiency at a concentration of 10 g / L avocado seed extract (ASE) was obtained at 74.56% with weight loss method and 68.38% with potentiometric polarization method. Corrosion inhibition efficiency was found to be greater with increasing ASE concentration. Polarization studies show that the avocado seed extract is a mixed corrosion inhibitor. SEM images on mild steel with the addition of ASE showed the formation of a thin layer on the mild steel surface. OH and CN functional groups appear on the FT-IR spectrum of ASE. These functional groups interact with iron on the steel surface to form a thin layer that can inhibit corrosive ion attacks from sulfuric acid solutions. (paper)