Influence of ilmenite ore particles as pigment on the anticorrosion and mechanical performance properties of polyamine cured epoxy for internal coating of gas transmission pipelines

• Published in: Egyptian journal of petroleum Vol. 27; no. 4; pp. 427 - 436
• Main Authors: Al-Sabagh, A.M., Abdou, M.I., Migahed, M.A., Fadl, A.M., Farag, Ahmed A., Mohammedy, M.M., Abd-Elwanees, S., Deiab, A.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2018
• Subjects: Anticorrosion behavior; EIS; Epoxy coating; Ilmenite ore; Mechanical properties; SEM; Ilmenite ore; Mechanical properties; SEM; Anticorrosion behavior; Epoxy coating; EIS
• ISSN: 1110-0621
• DOI: 10.1016/j.ejpe.2017.07.005

The lamellar-shaped ilmenite particles with flaky – like nature. [Display omitted] •Micro-sized ilmenite ore particles were obtained to be used as bi-functional modifier.•Salt spray test was studied to investigate anticorrosion behavior of ilmenite epoxy coating on the carbon steel surface.•EIS measurements were performed to assure the corrosion protection performance of ilmenite epoxy coating.•The mechanical properties for the investigated epoxy coated films were studied through adhesion pull-off, impact and bend tests. In the present work, Different high build epoxy coating formulations cured by polyamine hardener were modified by incorporation various concentrations (50, 75 and 100%) of processed micro-sized ilmenite ore (FeTiO3) as pigment to replace all inorganic solids content to form a highly cross linked ilmenite epoxy adduct in three dimensional network. X-ray diffraction (XRD) analysis was implemented to assure the phase identification of the crystalline ilmenite particles. Dielectric light scattering measurements were accomplished to measure the particle size distribution of micro-sized ilmenite particles. The lamellar shape of the prepared ilmenite pigment particles (FeTiO3) was illustrated by transmission electron microscopy (TEM) investigation. Flaky-like nature and the arrangement in overlapping plates of ilmenite particles were confirmed by scanning electron microscopy (SEM) technique. The anticorrosion behavior of the considered ilmenite epoxy coating formulations against unmodified blank coating were studied by accelerated corrosion experiment (salt spray chamber) after 500h exposure in 5% NaCl solution. To confirm the previous concept, the electrochemical behavior of cured ilmenite epoxy coated steel films against unmodified epoxy in oil-wells formation water has been studied by electrochemical impedance spectroscopy (EIS) investigation. The mechanical performance properties for these films were investigated via adhesion pull-off, bend and impact coating tests to confirm their application efficiency. From the recorded results it was found that, the inhibition effect of various coating formulations was attributed to the flaky-like character of dispersed ilmenite particles which aligned parallel to the steel surface through the epoxy base matrix producing a shield of overlapping plates. This alignment enhanced protection by providing a protective barrier, increasing the film reinforcement and enhancing the inter-coat adhesion.