# Effect of H2S on Fe corrosion in CO2-saturated brine

E. Abelev, J. Sellberg, T. A. Ramanarayanan, S. L. Bernasek

Research output: Contribution to journalArticle

51 Scopus citations

### Abstract

The effect of H2S at ppm level concentrations on iron corrosion in 3 wt% NaCl solutions saturated with CO2 in the temperature range of 25-85 °C is examined using electrochemical and surface science techniques. Small H2S concentrations (5 ppm) have an inhibiting effect on corrosion in the presence of CO2 at temperatures from 25 to 55 °C. At 85 °C, however, 50 ppm H2S is needed to provide significant corrosion inhibition. At higher H2S concentrations, the corrosion rate increases rapidly, while still remaining below the rate for the H2S-free solution. Characterization of the iron surfaces after corrosion was carried out using X-ray photoelectron spectroscopy and X-ray diffraction. A sulfur peak (S2p) is observed at a binding energy of 161.8 eV in all cases, attributable to disulfide $$({\text{S}}-{2}{2-})$$ formation. Corrosion protection in the temperature range 25-55 °C can be attributed to Fe(II) bonded to S and O. At 85 °C, protection of the iron surface is most likely due to FeS2 formation. Morphological changes on the iron surface after exposure to H2S containing solutions were observed by SEM. A thin protective film was seen after exposure to solutions containing 5 ppm H2S at 25 °C, while at 85 °C, with the addition of 50 ppm H2S to CO2-saturated brine solution, a dense protective film was formed on the iron surface.

Original language English (US) 6167-6181 15 Journal of Materials Science 44 22 https://doi.org/10.1007/s10853-009-3854-4 Published - Nov 1 2009

### All Science Journal Classification (ASJC) codes

• Materials Science(all)
• Mechanics of Materials
• Mechanical Engineering