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Corrosion of Copper Alloys in Natural Seawater: Effects of Hydrodynamics and Ph

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Corrosion of Copper Alloys in Natural Seawater: Effects of Hydrodynamics and Ph Corrosion of copper alloys in natural seawater : effects of hydrodynamics and pH Maria Leonor Carvalho To cite this version: Maria Leonor Carvalho. Corrosion of copper alloys in natural seawater : effects of hydrodynamics and pH. Analytical chemistry. Université Pierre et Marie Curie - Paris VI, 2014. English. NNT : 2014PA066304. tel-01207012 HAL Id: tel-01207012 https://tel.archives-ouvertes.fr/tel-01207012 Submitted on 30 Sep 2015 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. THESE DE DOCTORAT DE L’UNIVERSITÉ PIERRE ET MARIE CURIE Spécialité Chimie Physique et Chimie Analytique Présentée par Maria Leonor DE CASTRO REBELO DE AZEVEDO CARVALHO Pour obtenir le grade de DOCTEUR DE L’UNIVERSITE PIERRE ET MARIE CURIE Sujet de la thèse : Corrosion of copper alloys in natural seawater – Effects of hydrodynamics and pH Soutenue le : 29 septembre 2014 devant le jury composé de : Mme. Nadine Pébère Directrice de recherche, CNRS Rapporteur Mme. Judit Telegdi Professeur, RCNS - HAS Rapporteur M. Bernard Tribollet Directeur de recherche, CNRS Examinateur M. Philippe Marcus Directeur de recherche, CNRS Examinateur Mme. Pierangela Cristiani Chercheur, RSE SpA Examinateur Mme. Isabelle Frateur Chargée de recherche, CNRS Directrice de thèse ACKNOWLEDGEMENTS First and foremost I would like to express my sincere appreciation to my advisors Isabelle FRATEUR and Pierangela CRISTIANI for giving me an opportunity to work on this interesting topic and for providing me great guidance and support through the course of this research work. I am also thankful to Philippe MARCUS for encouraging my research and for allowing me to work at his laboratory. I would like to express my special thanks to Sandrine ZANNA for the XPS training and Antoine SEYEUX for the ToF-SIMS training, from the research group Physical Chemistry of Surfaces (LPCS), Chimie-Paristech. They were my primary resource for getting my surface analysis questions answered. Special thanks also to Blanca TORRES BAUTISTA for welcoming me at LPCS, helping me polishing samples, sharing scientific results and having good time during our “formulas”. I am grateful to Bernard TRIBOLLET and the Laboratory of Interfaces and Electrochemical Systems (LISE) for the scientific advices, knowledge, many insightful discussions and suggestions. I will definitely get stuck in EIS results without your help. Special thanks also to Iwona BEECH, Magdalena SZTYLER and Jemimah DOMA from the University of Portsmouth, UoP, to have helping me performing all the genetic studies. I also want to thank all current colleagues from RSE, SpA: Angelo PREVITALLI, Anna TOPPETTI, Claudia IMPOSIMATO, Claudio VANNINI, Dany CAM, Edoardo GUERRINI, Fiorella GRASSO, Flavia TULLI , Leonardo NERICCIO, Lidia FERRAVANTE and Michela TRIBUZIO. They provided a great atmosphere and lots of fun. Thank you for your motivation and support. A special thanks also to Giorgio PERBONI, from CESI. I thank you for your patience in helping me and nice travels to Piombino! The research leading to these results has received funding from the Marie Curie European Community's Seventh Framework Programme (FP7/2007–2013) under grant agreement n°238579, BIOCOR Initial Training Network (www.biocor.eu/ip7). The BIOCOR project gave me this incredible opportunity to collaborate with research institutes across Europe and to work with the greatest experts within the field of biocorrosion. All that was possible thanks to an excellent project coordination and management and I want to thank for that Régine BASSEGUY, Vincent BIRRIEN and Jennifer STEPHENSON. My sincere thanks also goes to all my BIOCOR colleagues, all senior scientists and professors. M.L.CARVALHO Last but not least, I can never add enough words to express how grateful I am for the endless support of my family. My father Antonio CARVALHO and also Ana COELHO have always provided me with unconditional love, support and motivation. Without their faith in me, I could not have made it this far (Obrigada pai!). Finally, and most importantly, I would like to express much gratitude and love to my beloved husband Giovanni VARGIU. Without his patience, invaluable support, encouragement and “editing assistance”, I would not have been able to complete this work. M.L.CARVALHO This thesis is lovingly dedicated to my mother, who will always be missed. I love you mommy! M.L.CARVALHO TABLE OF CONTENTS CHAPTER 1 – SCIENTIFIC BACKGROUND ....................................................................... 1 1.1 Cooling water systems in power supply facilities ......................................................... 1 1.1.1 Types of condensers ........................................................................................... 2 1.1.2 Types of cooling waters ....................................................................................... 3 1.1.3 Constituent materials of cooling water systems ................................................... 4 1.1.4 Cooling water systems operating problems.......................................................... 6 1.1.5 Cooling circuits tubes cleaning methods .............................................................. 9 1.1.6 Chlorination ......................................................................................................... 9 1.2 Corrosion of copper and its alloys in aqueous environments......................................11 1.2.1 Galvanic corrosion ..............................................................................................19 1.2.2 Pitting corrosion ..................................................................................................20 1.2.3 Dealloying ...........................................................................................................20 1.2.4 Ammonia attack ..................................................................................................21 1.2.5 Sulfide attack ......................................................................................................21 1.2.6 Erosion-corrosion ................................................................................................22 1.2.7 Microbiologically influenced corrosion (MIC) .......................................................23 1.3 Effect of different parameters on the corrosion behavior of 70Cu-30Ni alloy and Al brass ..................................................................................................................................25 1.3.1 Effect of iron and nickel.......................................................................................26 1.3.2 Effect of temperature ..........................................................................................27 1.3.4 Effect of pH .........................................................................................................27 1.3.4 Effect of oxygen content .....................................................................................29 1.3.5 Effect of polluted seawater ..................................................................................29 1.3.6 Effect of water velocity ........................................................................................30 1.3.7 Effect of seawater treatments .............................................................................30 1.3.8 Effect of suspended particles and mud ...............................................................31 1.3.9 Effect of biomolecules .........................................................................................32 1.4 Aim of this thesis and research strategy ....................................................................32 1.5 Thesis outline ............................................................................................................33 CHAPTER 2 – MATERIALS AND METHODS .....................................................................36 2.1 Studied metallic materials and electrolytes ................................................................36 2.1.1 Metallic materials ................................................................................................37 2.1.1.1 Field experiments - electrodes and surface preparation ..................................39 2.1.1.2 Laboratory experiments - electrodes and surface preparation .........................40 2.1.2 Electrolytes .........................................................................................................42 2.1.2.1 Field experiments ............................................................................................42 Natural seawater (NSW) ................................................................................42 Treated natural seawater (TNSW) .................................................................43 2.1.2.2 Laboratory experiments ...................................................................................43 Filtered natural seawater (FNSW) ..................................................................43 Artificial seawater (ASW) ...............................................................................43
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