Adsorption and Inhibiting Mild Steel Corrosion in Natural Lemon and Lime Citrus Fruit Juices by Alanine

Adsorption and inhibiting mild steel corrosion in natural lemon and lime citrus fruit juices by Alanine was investigated using weight loss (WL) and potentiodynamic polarization (PDP) measurements. The results obtained revealed Alanine to be an excellent inhibitor in the citrus fruit environments with obvious decline in degradation rate as Alanine concentration increases. Alanine adsorption on mild steel follows Temkin’s adsorption isotherm and thermodynamic adsorption values at 298 K revealed a physical adsorption in the two media. PDP results revealed that Alanine might behave as mixed or cathodic type inhibitor; this depends on the pH of the citrus fruit juices. The data obtained from the two different techniques: weight loss (WL) and potentiodynamic polarization (PDP) are in tandem with each other. The scanning electron microscope (SEM) images further validate the results.