Comparison of Corrosion Protection Efficiency of Two Kinds of Amino Acids

Abstract

Corrosion is an inevitable natural phenomenon. The amino acids are green corrosion inhibitors due to their nontoxicity and biodegradability. For this reason they are a good choice for corrosion protection. As inhibitors, we have used two amino acids, lysine and methionine. They have shown good inhibitor properties in protection of low allow carbon steel against the corrosion in acidic media. The aim of this study is to compare corrosion protection efficiency of these amino acids. Material under investigation is low alloy carbon steel marked as: Steel 39, Steel 44 and the corrosion media is: 1M H2SO4 + 10 -3 mol/L Cl -(in form of NaCl). A Tafel polarization technique was used for investigation of corrosion inhibitor efficiency. The results present that methionine is more protective again acidic corrosion and the steel 44 is more sustainable again sulfuric acidic corrosion. The best case in the respect of corrosion sustainability for steel 44 is in presence of 1g/L methionine with protection efficiency respectively 81.27%.