Carbon steel corrosion in clay-rich environment

International audienceWe investigated the carbon steel corrosion in carbon dioxide clay-rich environment to understand its behavior under geological conditions. The results show the formation of magnetite as the main corrosion product in the first step of the corrosion process, followed by the formation of different corrosion products with complex mixtures of iron-oxide, hydroxycarbonate, hydroxychloride and sulfide phases. These results strongly contrast with similar experiments conducted under H-2 atmosphere where the major corrosion products consisted of iron sulfides. It appears then important to consider all the geochemical parameters including gas composition to better study corrosion of steel buried in geological formations. (C) 2014 Elsevier Ltd. All rights reserved