• Ziomek-Moroz, M.
• Beck, J.
• Holcomb, G.
• Fedkin, M.
• Lvov, S.
• Tylczak, J.

Abstract

In aqueous phase saturated with CO2, X-65 sample underwent general corrosion with formation of FeCO3. In supercritical CO2 containing water phase, two major regions are present on the sample surface after the EIS experiment. One region covered with corrosion products identified as FeCO3 and the other containing Fe, oxygen, and carbon-rich islands embedded in metal matrix identified as {alpha}-Fe. Precipitation of FeCO3 from Fe2+ and CO3 2- is responsible for formation of passive layer in oxygen-deficient, CO2 rich aqueous environment. Mechanisms of corrosion degradation occurring in supercritical CO2 as a function. Transport of supercritical CO{sub 2} is a critical element for carbon capture from fossil fuel power plants and underground sequestration. Although acceptable levels of water in supercritical CO{sub 2} (up to {approx} 5 x 10{sup -4}g/dm{sup 3}) have been established, their effects on the corrosion resistance of pipeline steels are not fully known. Moreover, the presence of SO{sub 2}, O{sub 2} impurities in addition to the water can make the fluid more corrosive and, therefore, more detrimental to service materials. Also, in this case, limited data are available on materials performance of carbon steels. to advance this knowledge, other service alloys are being investigated in the high pressure high temperature cell containing impure CO{sub 2} fluids using reliable non-destructive in-situ electrochemical methods. The electrochemical results are being augmented by a number of surface analyses of the corroded surfaces.

Topics

• surface
• Carbon
• corrosion
• phase
• experiment
• Oxygen
• steel
• precipitation
• electrochemical-induced impedance spectroscopy