Effect of CO2 Partial Pressure on the Corrosion Inhibition of N80 Carbon Steel by Gum Arabic in a CO2-Water Saline Environment for Shale Oil and Gas Industry

Gaetano Palumbo; Kamila Kollbek; Roma Wirecka; Andrzej Bernasik; Marcin Górny

doi:10.3390/ma13194245

Effect of CO₂ Partial Pressure on the Corrosion Inhibition of N80 Carbon Steel by Gum Arabic in a CO₂-Water Saline Environment for Shale Oil and Gas Industry

Materials (Basel). 2020 Sep 23;13(19):4245. doi: 10.3390/ma13194245.

Authors

Gaetano Palumbo¹, Kamila Kollbek², Roma Wirecka^{2

3}, Andrzej Bernasik³, Marcin Górny⁴

Affiliations

¹ Department of Chemistry and Corrosion of Metals, Faculty of Foundry Engineering, AGH University of Science and Technology, 30-059 Krakow, Poland.
² Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, Mickiewicza St. 30, 30-059 Kraków, Poland.
³ Department of Condensed Matter Physics, Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Mickiewicza St. 30, 30-059 Krakow, Poland.
⁴ Department of Cast Alloys and Composites Engineering, Faculty of Foundry Engineering, AGH University of Science and Technology, 30-059 Krakow, Poland.

Abstract

The effect of CO₂ partial pressure on the corrosion inhibition efficiency of gum arabic (GA) on the N80 carbon steel pipeline in a CO₂-water saline environment was studied by using gravimetric and electrochemical measurements at different CO₂ partial pressures (e.g., PCO2 = 1, 20 and 40 bar) and temperatures (e.g., 25 and 60 °C). The results showed that the inhibitor efficiency increased with an increase in inhibitor concentration and CO₂ partial pressure. The corrosion inhibition efficiency was found to be 84.53% and 75.41% after 24 and 168 h of immersion at PCO2 = 40 bar, respectively. The surface was further evaluated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), grazing incidence X-ray diffraction (GIXRD), and X-ray photoelectron spectroscopy (XPS) measurements. The SEM-EDS and GIXRD measurements reveal that the surface of the metal was found to be strongly affected by the presence of the inhibitor and CO₂ partial pressure. In the presence of GA, the protective layer on the metal surface becomes more compact with increasing the CO₂ partial pressure. The XPS measurements provided direct evidence of the adsorption of GA molecules on the carbon steel surface and corroborated the gravimetric results.

Keywords: carbon steel N80; corrosion inhibition; gum arabic; high-pressure CO2 corrosion.