Abstract
Carbon dioxide (CO2) is considered to be easier to transport over moderate distances
when turned into supercritical state (dense phase) than at any other state. Because of this reason,
the transportation of CO2 during carbon capture and storage requires CO2 to be at its supercritical
state. CO2 temperature profile from different regions causes CO2 to deviate between supercritical
and subcritical state (gas/liquid phase). In this study the influence of sulphur dioxide (SO2) on
the corrosion of carbon steel was evaluated under different SO2 concentrations (0.5, 1.5 and 5%)
in combination with subcritical CO2. Scanning Electron Microscopy (SEM), X-Ray Diffraction
(XRD) and Energy-Dispersive X-ray Spectroscopy (EDS) were used to characterize the CO2
corrosion product layer formed on the carbon steel surface. The weight loss results showed that
corrosion rate increased with SO2 concentration with corrosion rate up to 7.45 mm/year while at
0% SO2 the corrosion rate was 0.067 mm/year.