1995/11/23 by Claudius Gros, Maha Mehanna · 2 citations
Engineering · Environmental Science · Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Corrosion Behavior and Inhibition #Metal Extraction and Bioleaching #Microbial Fuel Cells and Bioremediation #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #cond-mat
paper · pdf · doi:10.1103/physrevb.53.6865
published as Phys. Rev. B, Vol.53 6865(BR) (1996) · Phys. Rev. B (Brief Report), in press
arxiv created 1995/11/23 · openalex publication_date 2009/01/19 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/02
Microbially influenced corrosion (MIC) costs billions of euros per year. It is commonly agreed that sulphate-reducing bacteria (SRB) play a key role in anaerobic MIC of steels. In spite of this, laboratory experiments have difficulty in reproducing the corrosion of steels that is observed in natural environments. Moreover, they do not explain what triggers corrosion since SRB, ubiquitous in natural environments, do not systematically induce corrosion. The aim of this work was to evaluate the relevance of new electron transfer mechanisms between steels and proteins or microbial cells in the domain of MIC. The first part of the thesis evaluates the impact of [Fe]-hydrogenase on the anaerobic corrosion of mild steels. The direct catalysis of proton reduction by hydrogenases has often been suggested in the literature; here, it is clearly demonstrated. Hydrogenase from Clostridium acetobutylicum, whether it is active, deactivated on denatured, can accelerate the corrosion of mild steel. The presence of a phosphate medium makes the interpretations more complex without modifying the mechanism. A new hypothesis implying the crucial role of iron-sulphur clusters contained in the protein is brought to light. Corrosion catalysis by hydrogenases could be compared with well-known mechanisms of corrosion catalysis by iron sulphide. In this case, the redox state of iron-sulphur clusters would play a key role in the occurrence of corrosion. The second part elucidates the role of Geobacter sulfurreducens in anaerobic corrosion of three types of steels: mild steel (1145), ferritic (403) and austenitic steels (304L and 316L). Results show, for the first time, that adherent bacterial cells induce open circuit potential ennoblement of steels and accelerate the corrosion of slightly alloyed steels by a direct electron transfer mechanism. Depending on the concentrations of the electron acceptors and donors in the medium, G. sulfurreducens could either enhance corrosion propagation by direct catalysis of proton reduction or, in the absence of acceptors and with an excess of donors, protect against corrosion. Thus the occurrence of corrosion relies on the unfavourable conjunction of many parameters. These results obtained in laboratory conditions open new paths for investigating MIC in natural environments.