Document Type : Original Article
Electrochemistry and Material Science Unit, Department of Chemistry, Federal University, Otuoke, Bayelsa State, Nigeria
Department of Physics, Michael Okpara University of Agriculture, Umudike, Abia State, Nigeria
The corrosion inhibition of API 5L X60 pipeline steel in oil well acidizing fluid stimulated with 1.0 M HCl by Tranexamic Acid (TXA) was investigated using potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS) and the conventional gravimetric or weight loss (WL) techniques at temperatures ranging from 303 to 323 K. Surface morphological analysis was carried out using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX). The compound showed high inhibition activity with 98.9% inhibition efficiency at 3.0 g/L concentration of TXA. Polarization analysis indicates that TXA acts as mixed-type inhibitor. The observed decrease in double layer capacitance and an increase in charge transfer resistance obtained from EIS analysis confirmed that TXA performed well as a corrosion inhibitor for X60 steel in 1.0 M HCl medium, ascribed to the adsorption of Tranexamic Acid molecules onto the X60 steel surface. Weight loss analysis showed that inhibition efficiency is increased with the increase of TXA concentration and exposure time while decreased with temperature rise. The adsorption of TXA onto the surface of the X60 steel obeys Langmuir adsorption isotherm. SEM-EDX analysis affirmed the formation of protective adsorbed film of Tranexamic Acid onto the steel surface.