CORROSION INHIBITION OF MILD STEEL IN NaCl AND HCl SOLUTIONS BY AMINO ACIDS EXTRACTED FROM SOYBEAN RESIDUE

Abstract

The influence of some factors to extraction yield of amino acids from soybean residue (SR) was investigated. The composition of amino acids extracted from SR was determined by HPLC/MS-MS. The inhibitive effect of amino acids on mild steel in NaCl solution and HCl solution were investigated by potentiondyamic polarization. As a result, we found that the optimal condition to extract amino acids from SR with the yield of amino acids extraction was 47.10 % of the weight (based on the oven dried powder of SR), amino acids extracted from SR consist of 17 amino acids, and the mild steel inhibition efficiency of amino acids was 74.71 % in 3.5 % NaCl and 80.20 % in 0.5 M HCl.