No abstract

Polymer coating systems are classically applied on a metal surface to provide a dense barrier against the corrosive species. Cathodic protection is used for many applications at the same time than coatings to protect the metal structures from corrosive attack when the coating is damaged. However, the current demand will increase with the disbonded areas; moreover, the reactions that take place at the cathode can cause a progressive enlargement of the unbonded area. Self-healing coatings were considered as an alternative route for efficient anticorrosion protection while maintaining a low demand in cathodic protection. Such coatings typically incorporate micro or nanocapsules that contain film-formers and repair the coating damage when the coating is scratched. Selfhealing systems were developed for metal structures under cathodic protection using specific-film formers sensitive to the electrical field and pH encountered in the vicinity of a default on a coated structure under cathodic protection. The present paper describes the principle of this novel self-healing concept and discusses the healing efficiency on the basis of laboratory results. Electrochemical Impedance Spectroscopy was used to evaluate the performance of the barrier efficiency and continuous current demand monitoring assessed the ability of specific film-formers to provide self-healing and repair defects generated through the coating to the metal.

International audienceThe aim of this paper is to review some of the parameters influencing the corrosivity of alkanolamine solvents used for natural gas purification or for CO2 capture. In the light of literature data and of new experimental results, the influences of temperature and of acid gas loading are discussed. These two parameters appear to have a strong impact on corrosion rates of carbon steel, with extrapolated corrosion rates of several tens of mm/year for the highest temperature and acid gas loading condition

Polypropylene compounds containing organophilic layered silicates were prepared by means of melt extrusion at 180°C. We have studied the effect of the coupling agent on morphology development and mechanical properties. We are convinced of the importance of both the chemistry and the process conditions to elaborate nanocomposites with optimized properties.

Re´sume´-Corrosion dans les proce´de´s utilisant des alcanolamines pour le captage du CO 2 en post-combustion -Les proce´de´s de captage et de stockage du CO 2 occupent une place importante dans les strate´gies visant a`limiter les e´missions industrielles de gaz a`effet de serre. Les proce´de´s de captage en post-combustion par solvant chimique de type alcanolamine sont bien adapte´s au traitement d'e´missions ponctuelles massives issues de combustibles fossiles, rencontre´es notamment dans les centrales thermiques au charbon et au gaz, ou les industries side´rurgiques ou de production de ciment. La technologie utilisant le principe d'absorptionde´sorption par les alcanolamines est une des voies les plus matures a`ce jour : elle est en effet de´ja`mise en oeuvre, par exemple pour la de´sacidification du gaz naturel, bien qu'a`une e´chelle sensiblement plus petite. L'ope´ration de telles unite´s pour le traitement des fume´es de combustion pre´sente toutefois de nombreux challenges, parmi lesquels la corrosion des e´quipements tient une place importante. Le but de cet article est de pre´senter une revue des connaissances sur cet aspect particulier. Dans une premie`re partie, l'expe´rience issue de plusieurs de´cennies d'utilisation de proce´de´s aux alcanolamines dans le domaine de la production d'huile et de gaz est pre´sente´e. Dans une seconde partie, les risques spe´cifiques associe´s aux particularite´s des proce´de´s de captage du CO 2 en post-combustion sont identifie´s et discute´s. Diffe´rentes strate´gies de maıˆtrise de la corrosion sont de´crites, et certains axes prioritaires en matie`re de recherche et de´veloppement sont propose´s. Enfin, certaines difficulte´s en vue du transport du CO 2 issu du captage puis de son injection a`fin de stockage ge´ologique sont mises en avant, avec des recommandations strictes sur les teneurs maximales en impurete´s pour disposer en toute surete´du CO 2 issu de ce proce´de´.Abstract -Corrosion in CO 2 Post-Combustion Capture with Alkanolamines -A Review -CO 2 capture and storage plays an important part in industrial strategies for the mitigation of greenhouse gas emissions. CO 2 post-combustion capture with alkanolamines is well adapted for the treatment of large industrial point sources using combustion of fossil fuels for power generation, like coal or gas fired power plants, or the steel and cement industries. It is also one of the most mature technologies to date, since similar applications are already found in other types of industries like acid gas separation, although not at the same scale. Operation of alkanolamine units for CO 2 capture in combustion fumes presents several challenges, among which corrosion control plays a great part. It is the aim of this paper to present a review of current knowledge on this specific aspect. In a first part, lessons learnt from several decades of use of alkanolamines for natural gas separation in the oil and gas industry are discussed. Then, the specificities of CO 2 post-combustion capture are presented, and their conseq...