Performance of unprecedented synthesized biosurfactants as green inhibitors for the corrosion of mild steel-37-2 in neutral solutions: a mechanistic approach

Abstract

The inhibition impacts of two novel synthesized green biosurfactants (B-Surf.), namely, sodium N-dodecyl asparagine (AsS) and sodium N-dodecyl arginine (ArS), on the dissolution of mild steel alloy (MS-37-2), in aqueous sodium chloride solutions was inspected using various techniques. Increased concentration of NaCl solution resulted in an increase in the corrosion rate of MS-37-2. Inhibition efficiencies of B-Surf. compounds were found to increased with increase inhibitor concentrations. The synergistic inhibition action between B-Surf. inhibitors and Zn2+, Al3+ and Ce4+ on the dissolution behavior of steel alloy in NaCl solutions was investigated and interpreted. The surface morphology of the MS-37-2 surface was observed using a scanning electron microscopy (SEM). This adsorption follows Langmuir isotherm. The evaluated thermodynamic functions supported the mechanism of physical adsorption of the inhibitors. The mechanisms of corrosion and its inhibition of MS-37-2 in NaCl solutions were interpreted.

Keywords

• mild steel-37-2
• biosurfactants
• corrosion
• green inhibitors
• adsorption