Chukanovite (Fe2(OH)2CO3) identified as a corrosion product at sand-deposited carbon steel in CO2-saturated brine

Chukanovite (Fe2(OH)2CO3) has been identified by synchrotron-sourced infrared microspectroscopy as the main corrosion product at the sand-deposited carbon steel corroded in CO2-saturated brine at 80 °C. Siderite has been shown as a minor corrosion product at the sand-deposited steel, and the only product at the sand-free steel. The sand-deposited steels have similar general corrosion rates as the sand-free steels, but were susceptible to localized corrosion. These differences are related to the presence of the sand-deposit at the surface that influences the local micro-environment and promotes the formation of the mixed layer of corrosion products (chukanovite and siderite) at the carbon steel.