Corrosion inhibition of carbon steel in artificial seawater by caprylate. (30th August 2022)

• Record Type: Journal Article
• Authors: Nwanebu, Emmanuel Onyekachi; Omanovic, Sasha
• Is Part Of: Canadian journal of chemical engineering. Volume 101:Number 3(2023)
• Page Start: 1286
• Page End: 1297
• Publication Date: 2022-08-30
• Subjects: carbon steel -- corrosion inhibition -- NaCl solution -- sodium caprylate; Chemical engineering -- Periodicals; Technology -- Periodicals; 660.05
• DOI: 10.1002/cjce.24560
• Languages: English
• ISSNs: 0008-4034

Abstract

Abstract: The corrosion inhibition efficiency of sodium caprylate (SC) in protecting carbon steel (CS) in aqueous 3.5 wt.% NaCl was studied. SC was found to enable good corrosion protection of CS, yielding a maximum corrosion inhibition efficiency of 80 ± 2%. The inhibition efficiency was shown to be directly proportional to the SC surface coverage, characterized by a two‐step adsorption isotherm. The adsorption of SC on CS in the lower SC concentration region was found to follow the Langmuir adsorption isotherm and the first‐order reversible adsorption kinetics. The corresponding Gibbs free energy of SC adsorption was determined to be −23.8 kJ · mol −1, indicating a highly spontaneous adsorption process. The scanning electron microscopy imaging of the SC‐inhibited CS showed that the surface exhibited good corrosion stability during a 72 h exposure to the test medium.