Sweet Corrosion Inhibition on API 5L-B Pipeline Steel

Abstract

Corrosion inhibition and adsorption behavior of two triazole derivatives on API 5L-B carbon steel in CO₂-saturated 3.5% NaCl solutions was investigated using potentiodynamic polarization, EIS and EFM techniques. Specimen surfaces were characterized using SEM, EDX and XRD. Results show that the two compounds are mixed-type inhibitors and inhibition efficiency increases with increasing concentrations. Adsorption of the two compounds is a mixed between chemisorptions and physisorption and obeys Langmuir adsorption isotherm. Activation energy and thermodynamic parameters were calculated. Surface analyses confirm the formation of iron nitrides on the metal surface, which supports results obtained from previous techniques.

Keywords:

• Acid corrosion
• carbon steel
• EIS
• polarization
• SEM
• XRD

Notes

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