Tesis sobre el tema "Alliages de stockage d'hydrogène"
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Lefèvre, Gauthier. "Propriétés physico-chimiques de nouveaux matériaux en couches minces pour le stockage d'hydrogène". Thesis, Artois, 2018. http://www.theses.fr/2018ARTO0406.
Hydrogen storage is probably the last lock facing the development of fuel cells system.Hydrogen is a non-harmful, non-polluting that can be used as an energy vector, allowing to produce fossil fuel free electricity efficiently and releasing only water.It could trigger the next technological and green revolution, marking the end of environmental concerns related to energy.Hydrogen is the most energetic gas. These double-edged caracteristics makes it attractive and unsafe at the same time. Solid state storage can be seen as a solution in spite of a moderate hydrogen uptake and a poor desorption process.In this context, research of new materials with enhanced physico-chemical properties is desirable and represent the aim of this work.This thesis is an investigation study. On the one hand, with the help of efficient theoretical structural prediction systems, an exploration of the infinite possibilities offered by metal alloys has been performed. On the other hand, pulsed laser deposition of metal thin films has been implemented to make use of its benefits.The present theoretical study has highlighted the influence of external strains on stability and emergence of alloys in numerous binary systems. In addition, a search for potential hydrides was carried out. Informations obtained are encouraging the use of similar prediction schemes in order to identify new systems.From metallic thin films made by pulsed laser ablation, deposition difficulties and disparities in procedures have been put forward. Nonetheless, singular morphologies have been achieved by this process, opening new insights for designing novel materials
Zeaiter, Ali. "Caractérisation et modélisation du comportement des alliages TiFe dédiés au stockage solide d'hydrogène. : Application à l'amélioration des performances d'un réservoir à hydrures métalliques". Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCD007/document.
He environmental and economic problems caused by the use of petroleum products and the scarcity of these fossil fuels have led to the search for alternative sources of energy, which are renewable and respectful of the environment. Many of these sources are intermittent and require storage solutions. Hydrogen gas appears as a good candidate for this function. The hydrogen element, abundant in nature, has in its gaseous form a calorific value of 140 MJ / kg, i.e. 2.5 times that of gasoline. The 'hydrogen' sector is based on 3 pillars: production, storage, distribution and use. The storage of hydrogen is traditionally carried out by compression, under pressures ranging from a few bars to several hundreds, and by liquefaction at 20 K. The low density of these two types of storage (42 and 70 kgH2 / m3) associated with serious problems of safety and mechanical design, make solid storage in metal alloys particularly relevant for some applications. This solution favors the development of safe, compact design tanks with a high density of 120 kgH2/m3for TiFe alloys, for example. This type of hydride has been retained in this work because it has operating conditions of temperatures and pressures that are relatively close to ambient conditions, and also because it does not contain rare earth elements. The aim of this study is to characterize and model the hydriding/dehydriding behavior of the TiFe0.9Mn0.1 alloy, in order to improve its performance when it is integrated into a storage system. We first tried to characterize the alloy TiFe0.9Mn0.1 in powder form by describing it morphologically, chemically and thermodynamically. Then, two strategies of improvement were tested, the first one based on a mechanical treatment by planetary ball milling, the second considers a thermochemical treatment at given temperature and duration. Both strategies accelerated the process of powder activation, but the planetary ball milling significantly impaired the apparent desorption kinetics. The thermo-chemical treatment did not degrade the equilibrium domains and thus did not have an adverse effect on the reaction kinetics. The two most important parameters of this treatment, temperature and holding time, have been optimized. Other parameters remain to be refined.In addition to this experimental characterization, we have undertaken to describe the hydriding / dehydriding reaction macroscopically. The model allows to account for the thermodynamic response of the hydride within a reservoir. This work presents the results obtained on a tank containing 4 kg of TiFe0.9Mn0.1 powder when different hydrogen loading / unloading scenarios are considered: (i) loading / unloading under constant pressure, (ii) loading / unloading under an initial dose ( Method of Sievert), iii) loading / unloading under inlet or outlet flux of hydrogen. For each scenario, the effect of the coupling with a heat exchange system on the filling / emptying times is analyzed and optimal operating conditions are proposed. Finally, a sensitivity study using the Morris method is presented, and the most influential parameters of the model on the reaction rates are identified. The design of a solid hydrogen storage system requires a good understanding of the macroscopic as well as the microscopic aspects of the hydriding reaction and therefore requires further research to find new directions for improving its performance
Ponthieu, Marine. "Nouveaux matériaux riches en Mg pour le stockage d’hydrogène : composés Mg6Pd1-xMTx (MT = Ni, Ag, Cu) massifs et nanoconfinés et nanocomposites MgH2-TiH2". Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST1139/document.
This thesis is dedicated to the study of novel magnesium-rich compounds for solid state hydrogen storage. The aim is to destabilize Mg hydride and accelerate its sorption kinetics by alloying and nanostructuration. The first family of compounds concerns the Mg6Pd1-xTMx (TM = Ni, Ag, Cu) pseudo-binary phases. Their structural properties and the effects of Pd substitution have been studied by X-ray diffraction, scanning electron microscopy and electron microprobe analyses. Their thermodynamics and kinetics of hydrogenation have been determined by solid-gas reaction. Different hydrogenation mechanisms take place depending on the substituting element. The stability of the metal-hydrogen system is altered by the nature of the phases formed during hydrogenation reaction. Thus, metal to hydride transformation is characterized by at least two absorption plateau pressures. The pressure of the first plateau is similar to that of Mg/MgH2 while the second one occurs at higher pressure. The enthalpy and entropy of reaction are determined to quantify the destabilizing effect of Pd by TM substitution. Best desorption kinetics are found for the Ni containing alloy thanks to the catalytic effect of the Mg2NiH4 phase formed on hydrogenation. The second approach aims to combine alloying with nanostructuration effects. Nanoparticles of Mg6Pd as small as 3 nm are confined into nanoporous carbon matrix. By comparing their hydrogenation properties with those of the bulk alloy, we demonstrate that not only the (de)hydrogenation kinetics are much faster for the nanoparticles, but also that their hydrided state is destabilized. Finally, MgH2-TiH2 nanocomposites were synthesized by mechanical milling under reactive atmosphere. The addition of a catalyst (TiH2) and Mg nanostructuration allow strongly accelerating the sorption kinetics of hydrogen in Mg. To understand the role of the TiH2 phase on the outstanding kinetics of these nanocomposites, their structural properties have been determined by X-ray and neutron diffraction. The existence of a coherent interface between Mg and TiH2 phases is of major importance to facilitate H-mobility within the nanocomposite. Furthermore, it is shown that the TiH2 inclusions inhibit the Mg/MgH2 grain growth, thus maintaining the composites nanostructure during their cycling
Ponthieu, Marine y Marine Ponthieu. "Nouveaux matériaux riches en Mg pour le stockage d'hydrogène : composés Mg6Pd1-xMTx (MT = Ni, Ag, Cu) massifs et nanoconfinés et nanocomposites MgH2-TiH2". Phd thesis, Université Paris-Est, 2013. http://tel.archives-ouvertes.fr/tel-00939180.
Liu, Yuchen. "Synthesis, structural characterization and electrochemical hydrogen storage properties of LaNi5 and La4MgNi19 alloys prepared by mechanical alloying". Electronic Thesis or Diss., Bourgogne Franche-Comté, 2024. http://www.theses.fr/2024UBFCA004.
Today's world is facing the imminent depletion of fossil fuels and serious environmental problems, and it is urgent to find clean and renewable energy sources. Hydrogen energy, as a clean energy source, is a potential candidate. In a hydrogen economy based on hydrogen energy, hydrogen storage is the biggest obstacle limiting its development. Metal hydrides have attracted attention due to their safety and high hydrogen storage properties. The first generation of commercial hydrogen storage alloy LaNi5-based alloy has excellent hydrogen storage performance and has been widely used in various fields. However, due to its low hydrogen storage capacity, it is difficult to meet the requires of the European Union for hydrogen storage materials. Scientists often use a single optimization method, such as element substitution, new synthetic routes, surface optimization, etc. However, few articles report optimization methods that combine the two methods.In this work, first principles were used to screen out the best element Cr to substitute Ni. Mechanical alloying was used to synthesize LaNi5 alloy and LaNi4Cr alloy. The micromorphology and phase composition of different samples produced with different ball milling parameters were characterized by SEM and XRD tests. The hydrogen storage performance of the sample was then tested, and the gaseous hydrogen storage performance and electrochemical performance of the sample were obtained. The hydrogen storage properties of all the above samples are compared with each other, and the results reflect the effectiveness of the combination of mechanical alloying and element substitution methods for the optimization of LaNi5.In addition, another optimization method of LaNi5 alloy was also carried out, that is, combining it with AB2 phase to form La4MgNi19 alloy. A total of 6 sets of parameters with different ball milling times and different precursors were used to synthesize La4MgNi19 alloy. The phase composition and hydrogen storage properties of all samples were obtained and compared with the hydrogen storage properties of LaNi4Cr. The results show that the hydrogen storage performance of La4MgNi19 alloy is better than that of LaNi5 alloy, but slightly worse than that of LaNi4Cr alloy.Finally, with the help of simulation software, the parameters of the LaNi4Cr alloy were introduced into the proven hydrogen storage tank model to explore the performance of this alloy in the hydrogen storage tank. After exploring the effects of different parameters on the hydrogen storage tank, water pipes were added to adjust the heat exchange. The results show that hydrogen storage tanks filled with LaNi4Cr have excellent performance
Huang, Liwu. "Élaboration, caractérisation et propriétés de stockage d'hydrogène électrochimique des alliages : Mg2Ni1-xMnx (x = 0, 0.125, 0.25, 0.375) et Mg2-xAlxNi (x = 0, 0.25) + 5 wt.% MWCNTs préparés par mécanosynthèse". Phd thesis, Université de Technologie de Belfort-Montbeliard, 2012. http://tel.archives-ouvertes.fr/tel-00720661.
Campesi, Renato. "Synthèse, caractérisation et étude des propriétés thermodynamiques d'hydrogénation de nanocomposites matériaux poreux / métaux-alliages". Phd thesis, Université Paris-Est, 2008. http://tel.archives-ouvertes.fr/tel-00461689.
Nguyen, Julien. "Stockage électrochimique d'hydrogène dans le carbure de titane". Limoges, 2013. https://aurore.unilim.fr/theses/nxfile/default/3ef7b178-91cc-4a1d-9d54-d5d078de92db/blobholder:0/2013LIMO4023.pdf.
This work deals with the feasibility of the electrochemical hydrogen insertion into the substoichiometric titanium carbides TiCx (0. 5 ≤ x ≤ 1) obtained by conventional reactive sintering (natural and hot pressing), and under the form of thin films, as obtained by magnetron reactive sputtering. The electrochemical hydrogen insertion in this material strongly depends on several parameters : (i) the elaboration process ; (ii) the crystalline structure ; and (iii) the stoichiometry of the carbide. The carbides TiCx obtained by hot pressing with x lower or equal to 0. 70 present an ordered crystalline structure where the (111) carbon plans are partially empty, allowing the hydrogen insertion into the material. On the contrary, the carbides prepared by reactive sintering at high temperature (2100°C) do not allow the hydrogen insertion whatever the carbide stoichiometry, because of the disorder of the carbon vacancies inside the crystalline structure. Nevertheless, it is possible to order these carbon vacancies by annealing at low temperature (730°C), this treatment rendering again the carbon plans (111) partially empty, and so, allowing the hydrogen to penetrate inside the titanium carbide with a diffusion coeffcient estimated at 1. 2 X 10-13 cm2. S-1 in TiC0. 60. The electrochemical reaction of oxidation of the titanium carbide was also studied, and it is demonstrated that TiC oxidizes into TiO2 accompanied by a CO2 release
Langohr, David. "Étude du stockage d'hydrogène par adsorption dans des carbones nanostructurés". Phd thesis, École Nationale Supérieure des Mines de Paris, 2004. http://pastel.archives-ouvertes.fr/pastel-00001383.
Langohr, David. "Etude du stockage d'hydrogène par adsorption dans des carbones nanostructurés". Paris, ENMP, 2004. http://www.theses.fr/2004ENMP1249.
El, Kharbachi Abdelouahab. "Etude des réactions complexes en phase solide pour stockage d'hydrogène". Thesis, Grenoble, 2011. http://www.theses.fr/2011GRENI010.
Hydrides for solid-state hydrogen storage are one of the future solutions - pollutant free - for the storage and the transport of energy. Among the candidates, LiBH4 was selected considering its high gravimetric hydrogen capacity (up to 13.6 wt.% H2). This material has thermodynamic and kinetic properties insufficiently established to be included in future applications. Its decomposition can be facilitated within the presence of the hydride MgH2. Thus, the composite MgH2-xLiBH4 (0< x< 3.5) reactivated by high energy ball-milling, was studied regarding its microstructural properties and stability of the phases. The desorption reaction of hydrogen, with or without additives, shows the appearance of additional phases accompanying the principal reaction. Heat capacity measurements of LiBH4 revealed the presence of an abnormal behaviour before the polymorphous transition (Ttrs = 386 K), attributed to the increase of crystal defects in agreement with the existence of a hypo-stoichiometric domaine LiBH4-ε observed at higher temperatures. The stability of the three-phase system LiBH4-LiH-B was studied resulting to the principal reaction of decomposition: LiBH4(s,l) → LiH(s) + B(s) + 1,5H2(g). Vapour pressure measurements of LiBH4 showed that H2 is the major component of decomposition with minor species such as B2H6 and BH3. The thermodynamic properties of LiBH4 were critically assessed, gathering the new data with those existing in the literature, in the aim of modelling of reactions occurring in hydride mixtures
Gagnon-Thibault, Évelyne. "Synthèse et caractérisation de matériaux polymères poreux pour le stockage d'hydrogène". Thesis, Université Laval, 2012. http://www.theses.ulaval.ca/2012/29167/29167.pdf.
Kelouwani, Sousso. "Stratégie de commande d'un système à énergie renouvelable avec stockage d'hydrogène". Thèse, Université du Québec à Trois-Rivières, 2002. http://depot-e.uqtr.ca/2579/1/000694556.pdf.
Bergeron, Guy. "Élaboration par voie liquide de l'intermétallique Mg¦2Ni destiné au stockage d'hydrogène". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ62045.pdf.
Charbonnier, Jean. "Etude de deux types d'hydrures métalliques pour le stockage réversible de grandes quantités d'hydrogène". Université Joseph Fourier (Grenoble), 2006. http://www.theses.fr/2006GRE10016.
The main subject ofthis study is hydrogen storage in two types ofmetal hydrides, from the synthesis of compounds with remarkable properties to the design of a tank prototype. Concerning the body centered cubic aIloys, we first aim at destabilizing the stable a vanadium hydride by modifYing the surroundings atoms of crystallographic sites occupied by hydrogen. Ln a second time, the elaboration of a specific microstructure, including an activating phase and storing matrix, lead us to extremely reactive compounds with a high storage capacity moreover stable while cycling. During the study of the magnesium hydride, we determined the influence and the optimum of MgH2 mechanical aIloying with a transition metal. The best kinetic properties have been obtained using energetic milling through the creation of numerous nucleation sites thanks to additive metal atoms. Ln addition, an upscaling study succeeds in the production of nanostructured MgH2 batches of 1 kg with similar properties compared to l!lboratory samples. . A metal hydride tank prototype for hydrogen storage, with a greatly flexible configuration, has finally been developed and will be the cornerstone of the thermal exchanges study in the tank and in the storing hydrogen compound
Charlas, Benoit. "Etude du comportement mécanique d'un hydrure intermétallique utilisé pour le stokage d'hydrogène". Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENI101/document.
It is harder and harder to find fossil fuels and it becomes therefore more and more expensive. Furthermore the environmental impacts of energy are more and more taken into account. For those reasons new solutions to produce, store, transport energy are currently researched and/or developed. Among those solutions, hydrogen system could be a good solution depending and how its main parts (production, storage, supply and use) are improved.This PhD is relative to hydrogen storage in intermetallic hydride compouds. Hydrogen tanks using these kind of materials have to allow good thermal control of the hydride powder especially because of the exothermicity of the hydriding and endothermicity of the unhydriding reaction. That's why the internal architecture of these vessels are often cellular, the cell walls playing the role of a thermal conductor. If the thermal aspects relative to these tanks are often studied, it is not the case of the mechanical phenomenon induced by the swelling and shrinking of the grains during absorption and desorption of hydrogène by the material. However, the mechanical interaction between the powder and the cell walls could endanger the tank.This PhD consists of two main parts. The first part is a mechanical study of the behavior of a Ti-Cr-V compound while the second is a mechanical modelling and analysis mainly by the Discretes Elements Method (DEM). Thanks to this work the main features and mechanical properties of the hydride (granulometry, matrix compaction, granular flow, powder density …) and their evolution due to cycling were measured. The influence of hydride grains rearrangement induced by hydride breathing were analysed experimentally. It lead to a progressive densification of the powder bed in instrumented cells that resulted in a decrease of porosity and an increase of stresses on cell walls. This effect was reproduced in discrete elements simulations of spherical and clump particles
Roumanie, Marilyne. "Microréacteur pour la catalyse hétérogèneApplications : Stockage d'hydrogène dans les hydrocarbures Filtre pour capteur gaz". Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2005. http://tel.archives-ouvertes.fr/tel-00012119.
Tayeh, Toufic. "Composés à base de magnésium pour le stockage et/ou la production délocalisée d'hydrogène". Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0011/document.
Hydrogen is a very important energy carrier. Indeed, it is abundant in the combined state and its combustion, very energetic, is non-polluting. However, the safest storage mode of this explosive gas is in the metal hydride form. Among metals, magnesium is one of the most promising one because its high mass capacity storage (7. 6%), low cost and natural abundance. However its kinetics of sorption are slow and its hydride MgH2 is very stable and has a poor thermal conductivity. The objective of this thesis is to resolve most of the weaknesses of magnesium by adding carbon fibers as reinforcement using the ball milling process, a way to ensure a good contact between the two, either by tape casting, a technique to help in the fibers’ orientation, for a maximum of thermal conductivity. We were therefore interested in the study of absorption / desorption kinetics, where an improvement was observed after the addition of carbon by grinding. A study of the thermal conductivity was also interesting, and the material prepared by tape casting, as expected, gave a very good result. On the other hand, we performed some hydrolysis’ tests to produce hydrogen. Having the problem of Mg(OH)2 formation on the surface, that blocks the reaction; different parameters were modified (e. G. PH, T°, particle size, U. S. ), which showed a positive impact on the hydrogen yield and reaction kinetics. Finally, two severe plastic deformation methods: i) cold rolling and ii) ECAP were applied to the TiH2 and MgH2 samples. Both techniques showed a destabilizing power of hydrides and therefore a decrease in the temperature of dehydrogenation. They even showed different behaviors than the mechanical grinding from microstrain and planes orientation point of view
Leh, David. "Optimisation du dimensionnement d'un réservoir composite type IV pour stockage très haute pression d'hydrogène". Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-00942731.
Santa, Cruz Bustamante Gabriela Victoria. "Contribution à l'étude d'un procédé de transport d'hydrogène dans les hydrocarbures cycliques pour l'industrie automobile". Lyon 1, 2005. http://www.theses.fr/2005LYO10244.
Roumanie, Marilyne. "Microréacteur pour la catalyse hétérogène. Applications : Stockage d'hydrogène dans les hydrocarbures. Filtre pour capteur gaz". Saint-Etienne, EMSE, 2005. http://www.theses.fr/2005EMSE0023.
This manuscript presents the design and the use of silicon microstructured reactor for heterogeneous catalysis and especially for the dehydrogenation of methylcyclohexane reaction. This reaction enables on one hand to store hydrogen and on the other hand to realise technological developments since it is endothermic and difficult to carry out. By consequence, a new microreactor obtained by DRIE was designed and capped with a Pyrex wafer. It bundles microheaters deposited by screen-printing and a high temperature metallic connection. It comprises either a catalyst coming from microtechnology, Pt film deposited by sputtering or a classic catalyst, platinum supported on alumina. For this last catalyst, the microreactor previously preoxidised is pretraited by oxygen plasma or liquid way so that the deposit to walls. The washcoat could be done in open microreactor by dip coating in the suspension or in closed microreactor under vacuum or by liquid circulation. After catalytic tests realised in a macroreactor, the Pt/Al₂O₃ catalyst was chosen to be inserted in the microreactor. The catalytic tests realised in a microreactor coupled with a mass spectrometer let to show the presence of hydrogen. In parallel, the microreactor was used as filter to improve gas sensor selectivity
D'ambra, Florian. "Evaluation du système de stockage de l'hydrogène sous forme de liquide organique transporteur d'hydrogène (LOHC)". Electronic Thesis or Diss., Université Grenoble Alpes, 2023. https://thares.univ-grenoble-alpes.fr/2023GRALI029.pdf.
Hydrogen is an excellent energy vector to compensate for the intermittence of renewable energies, if it is stored and transported safely at low cost. However, hydrogen possesses a very low-density gas, thus its transport and storage present many challenges, both in terms of the quantity transported and in terms of its containment.A potential answer to these problems consists in using LOHC (Liquid Organic Hydrogen Carrier) type organic molecules. These are capable of creating covalent bonds with hydrogen, thus improving the safety and handling of hydrogen while maintaining volumetric densities of hydrogen comparable to those of traditional storage systems. Indeed, LOHCs have hydrogen gravimetric densities at room temperature and atmospheric pressure that can be higher than those of 700 bar or cryogenic storage systems while limiting the associated risks. In general, LOHCs are liquid molecules capable of storing and producing hydrogen at a desired location and time through catalytic exothermic hydrogenation and endothermic dehydrogenation reactions. Thus, the transportation of hydrogen consists in transporting a liquid instead of a gas with the dehydrogenation carried out at the point of use of the hydrogen. The hydrogen-poor LOHC is the only by-product of the reaction that can then be reused to store hydrogen again. Nevertheless, the high energy cost to dehydrogenate these molecules is a barrier to the emergence of this technology. This thesis objetcives are therefore to determine new LOHC molecules whose dehydrogenation enthalpy is lower than the dehydrogenation enthalpy of the state of the art N-Ethylcarbazole (50 kJ/mol H2). Then, experimental tests will evaluate the suitability of these molecules for their hydrogenation and dehydrogenation reactions.In this thesis, the viability of potential LOHCs was previously evaluated by calculating their thermodynamic properties by ab-inito Density Functional Theory. The liquid temperature range, gravimetric and volumetric hydrogen densities, synthetic accessibility, and safety were also considered. Although no LOHC potential had a lower enthalpy than N-Ethylcarbazole, these criteria highlighted the interest of previously unstudied bifunctional LOHCs, i.e. LOHC systems whose molecules can store/release hydrogen in/from two different chemical functions such as an aromatic ring/saturated ring and a ketone/alcohol. The performance and reaction mechanisms of the 1-Cyclohexylethanol/Acetophenone couple were evaluated with commercial heterogeneous catalysts in hydrogenation and dehydrogenation batch systems in order to develop suitable reaction conditions for its cycling.Then, the LOHC degradation pathways were identified for hydrogenation and dehydrogenation and the formation of degradation products was related to the different components of the LOHC system. Modification of the carrier, additives and modification of the LOHC structure to Dicyclohexylmethanol/Benzophenone were thus tested to block the degradation pathways.A methodology to regenerate the dehydrated LOHC was also developed. A new couple, Dodecahydrofluoren-9-ol/Fluoren-9-one was suggested due to the increased conversion of Fluorene to Fluoren-9-one under the developed conditions. The effect of regeneration on the LOHC cycling was then tested.Finally, the LOHC Cyclohexylmethanol/Benzylbenzoate couple was studied to highlight the effect of replacing the ketone function with an ester. The effects of the modification on the reactivity and stability of the LOHC couple were rationalized
Marcus, Kylia. "Alliages multi-élémentaires comme matériaux innovants pour le stockage solide de l’hydrogène". Electronic Thesis or Diss., Université Grenoble Alpes, 2023. http://www.theses.fr/2023GRALI115.
Multiple principal element alloys (MPEAs) are an interesting new class of alloys for hydrogen storage. Unlike a conventional alloy in which 1 or 2 elements are added in small quantities to a high-concentration element, here at least 4 elements are mixed in almost equal proportions. Depending on the composition, the increase in mixing entropy can lead to the formation of a single-phase solid solution (mainly cubic or hexagonal in structure). Equilibrium pressure is generally less than 1 bar, which means that the hydride is thermodynamically stable. This low equilibrium pressure is not suitable for storage applications, as the dehydridation reaction requires a significant amount of energy to occur. In order to improve the first equilibrium pressure plateau, new compositions are designed on the basis of the AB type classification, with A a stable hydride-forming element and B an unstable hydride-forming element. This thesis deals with the synthesis, microstructural and structural studies and sorption properties of four-element alloys, mainly transition elements
Bisor, Caroline. "Compréhension des mécanismes de prise d'hydrogène des alliages de zirconium en situation de corrosion en conditions REP : impact des hydrures sur la corrosion du Zircaloy-4". Thesis, Evry-Val d'Essonne, 2010. http://www.theses.fr/2010EVRY0004/document.
Zirconium alloys are widely used as fuel claddings in Pressurized Water Reactors. However, the corrosion and hydriding lead to a progressive reduction of the use of Zircaloy-4 alloys whereas the Zr-1Nb alloy becomes a competitive material. In order to improve the understanding of their behaviour, two research axes were investigated: the determination of the hydrogen pick-up mechanism for each alloy and the impact of zirconium hydrides on Zircaloy-4 corrosion. Regarding the study of mechanisms, isotopic exchanges were carried out in D2O environment at 360°C and led (SIMS, ERDA) to the localization, in the oxide scales, of the limiting step for the hydrogen diffusion. The lower hydrogen pick-up fraction observed on Zr-1Nb alloy is rather due to a smaller hydrogen gradient in the oxide than to a lower value of the diffusion coefficient. Concerning the impact of hydrides on Zircaloy-4 corrosion, the characterization of pre-hydrided samples which were corroded in primary water at 360°C revealed several changes, as the presence of Zr3O sub-oxide at the inner metal/oxide interface, a lower fraction of β-ZrO2 in the oxide and a faster diffusion of oxygen species through grain boundaries of zirconia (TEM, µ-XRD, 18O isotopic experiments). Moreover, during oxidation, the hydrogen initially present in the hydride phase remains in the metallic matrix and leads to the allotropic transformation ZrH1 ,66 εZrH2. Finally, based on all those experimental results, a simultaneous mechanism of oxidation and hydrogen pick-up was proposed for the studied alloys
Girard, Grégory. "Étude de nouvelles formes de matériaux basés sur le magnésium pour le stockage réversible de grandes quantités d'hydrogène : effet d'addition d'éléments de transition". Grenoble 1, 2009. http://www.theses.fr/2009GRE10177.
The aim of this thesis was the principles of activation of MgH2 based materials for fast and reversible hydrogen storage. The relatively high temperature of reaction of hydrogen with magnesium is said a brake for a systematic application in terms of hydrogenstorage. Here, new alloys of Ca-Mg-Ni formula allowing working close to room temperature were characterised. Although weaker storage capacity was realised, it overpasses that of the reference LaNis. If hydrogen sorpion kinetics are commonly improved when exhibiting a fme microstructure up to nanometric crystallites, here an original work was devoted to the use of extrusion ECAP process. Activation of extruded Mg-based alloys was achieved successfully. Ball-milling of MgH2 powders with small amount of selected 3-d transition metals leads to marked improvements of the hydrogen absorptionldesorption kinetics of nanostructured powders. The diffusion mechanism involving the fine interfaces created in PLD deposits allows understanding the so-called catalytic process in a multilayer. Finally, the study of new alloys as synthesized under high-temperature and high-pressure was undertaken to understand the activation at atomic scale but in ternary metastable hydrides
Queylat, Benoît. "Compréhension de l'évolution de la fraction d'hydrogène absorbée par les gaines en alliages de zirconium". Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASN026.
In nuclear Pressurized Water Reactor (PWR), nuclear fuel is contained in zirconium alloy cladding tubes. As the cladding tube acts as the first containment barrier of fissile materials, protecting its physical integrity is fundamental. Under harsh environment (high temperature and pressure, neutron irradiation), claddings undergo oxidation and hydriding processes. Hydrogen uptake is detrimental to the integrity of claddings: when the hydrogen content reaches the solubility limit, precipitation of hydrides occurs, which may embrittle them. For the last decades, development of new zirconium-niobium alloys, as M5Framatome, allowed a large decrease of the hydrogen uptake by claddings. In addition, it has been observed that, opposite to Zircaloys, M5Framatome absorbs less hydrogen after ion-irradiation. Nevertheless, the reasons of this decrease in niobium containing alloys are still not well understood. Consequently, this PhD thesis follows multiple aims:· Understanding the hydrogen pickup evolution of the M5Framatome under simulated PWR conditions;· Understanding niobium’s role in hydrogen pickup;· Understanding irradiation effects on hydrogen pickup.To reach these goals, samples of M5Framatome (with 1 wt% niobium) and model alloys (containing 0.2 and 0.4 wt% of niobium) have been corroded in static autoclave in order to monitor the evolution of oxidation and hydrogen pick up kinetics. Neutron irradiation has been simulated by series of ion irradiations of pre-oxidized M5Framatome samples. Chemical analyses have been performed in order to understand mechanisms involved in the absorption and diffusion processes of hydrogen in the oxide layer at different spatial scales. All these tests have led to the following conclusions :· As long as the oxide layer thickness stays below 2.5 µm, the hydrogen pickup by the metal underneath is close to zero. Above that limit, the hydrogen pickup is proportional to the oxide layer thickness.· The hydrogen pickup in the metal is not limited by its absorption nor its diffusion in the oxide but by the transition from the oxide layer into the metal.· When the niobium content is below or equal to the solubility limit in α-Zr, the hydrogen pickup is proportional to the oxide thickness.· Ion irradiation in post-transition corrosion state decreases the oxidation and hydrogen pickup rates but has no effect on the hydrogen pickup fraction.Based on these various results, a hydrogen pickup mechanism in corrosion conditions has been suggested for the M5Framatome. It attempts to take into account the role of both the niobium inclusion and the irradiation effects observed in this work. In addition, empirical laws describing the evolution of hydrogen pickup fraction have been proposed and compared to data taken from nuclear reactors
Sáinz-García, Álvaro. "Dynamique de stockage souterrain de gaz : aperçu à partir de modèles numériques de dioxyde de carbone et d'hydrogène". Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30187/document.
Climate change mitigation is one of the major challenges of our time. The anthropogenic greenhouse gases emissions have continuously increased since industrial revolution leading to global warming. A broad portfolio of mitigation technologies has to be implemented to fulfill international greenhouse gas emissions agreements. Some of them comprises the use of the underground as a storage of various substances. In particular, this thesis addresses the dynamics of carbon dioxide (CO2) and hydrogen (H2) underground storage. Numerical models are a very useful tool to estimate the processes taking place at the subsurface. During this thesis, a solute transport in porous media module and various multiphase flow formulations have been implemented in COMSOL Multiphysics (Comsol, 2016). These numerical tools help to progress in the understanding of the migration and interaction of fluids in porous underground storages. Three models that provide recommendations to improve the efficiency, monitoring and safety of the storages are presented in this manuscript: two in the context of carbon capture and storage (CCS) and one applied to underground hydrogen storage (UHS). Each model focus on a specific research question: Multiphase model on CCS. The efficiency and long-term safety of underground CO2 storage depend on the migration and trapping of the buoyant CO2 plume. The wide range of temporal and spatial scales involved poses challenges in the assessment of the trapping mechanisms and the interaction between them. In this chapter a two-phase dynamic numerical model able to capture the effects of capillarity, dissolution and convective mixing on the plume migration is applied to a syncline-anticline aquifer structure. In anticline aquifers, the slope of the aquifer and the distance of injection to anticline crest determine the gravity current migration and, thus, the trapping mechanisms affecting the CO2. The anticline structure halts the gravity current and promotes free-phase CO2 accumulation beneath the anticline crest, stimulating the onset of convection and, thus, accelerating CO2 dissolution. Variations on the gravity current velocity due to the anticline slope can lead to plume splitting and different free-phase plume depletion time is observed depending on the injection location. Injection at short distances from the anticline crest minimizes the plume extent but retards CO2 immobilization. On the contrary, injection at large distances from anticline crest leads to large plume footprints and the splitting of the free-phase plume. The larger extension yields higher leakage risk than injection close to aquifer tip; however, capillary trapping is greatly enhanced, leading to faster free-phase CO2 immobilization. Reactive transport model on convective mixing in CCS. Dissolution of carbon-dioxide into formation fluids during carbon capture and storage (CCS) can generate an instability with a denser CO2-rich fluid located above the less dense native aquifer fluid. This instability promotes convective mixing, enhancing CO2 dissolution and favouring the storage safety
Bhouri, Maha. "Optimisation des transferts de chaleur dans un système de stockage d'hydrogène à base d'alanate de sodium". Thèse, Université du Québec à Trois-Rivières, 2012. http://depot-e.uqtr.ca/4414/1/030309563.pdf.
Kaddami, Mohammed. "Etude physico-chimique du système eau-nitrate d'aluminium-nitrate d'ammonium : application au stockage de l'énergie frigorifique". Lyon 1, 1986. http://www.theses.fr/1986LYO10057.
Roussel, Thomas Julien. "Simulation numérique de répliques de zéolithes en carbone : structures et propriétés d'adsorption en vue d'une application au stockage d'hydrogène". Aix-Marseille 2, 2007. http://theses.univ-amu.fr.lama.univ-amu.fr/2007AIX22029.pdf.
Hydrogen storage is the key issue to envisage this gas as an energy vector in the field of transportation. Porous carbons are materials that are considered as possible candidates. We have studied well-controlled microporous carbon nanostructures, carbonaceous replicas of mesoporous ordered silica materials and zeolites. We realized numerically the atomic nanostructures of the carbon replication of four zeolites : AlPO4-5, silicalite, and Faujasite (FAU and EMT). The faujasite replicas allow nanocasting a new form of carbon cristalline solid made of tetrahedrally or hexagonally interconnected nanotubes. The pore size networks are nanometric giving to these materials optimized hydrogen molecular storage capacities. However, we demonstrate that these new carbon forms are not interesting for a room temperature efficient storage compared to the void space of a classical tank. We showed that doping with alkaline element such as lithium one could store the same quantities at 300 bars than a classical tank at 700 bars. This result is a possible route to achieve interesting performances for on-board docking systems
Truche, Laurent. "Transformations minéralogiques et géochimiques induites par la présence d'hydrogène dans un site de stockage de déchets radioactifs". Phd thesis, Université Paul Sabatier - Toulouse III, 2009. http://tel.archives-ouvertes.fr/tel-00439788.
Hosni, Bilel. "Élaboration par mécano-synthèse d'alliages à base Ti-Fe : caractérisation de leurs propriétés de stockage électrochimique d'hydrogène". Thesis, Bourgogne Franche-Comté, 2018. http://www.theses.fr/2018UBFCA015.
Hydrogen is the potential solution to make a success of the energy transition of a current system basically based on fossil fuels towards a system friendly to environment. However, the storage of hydrogen is a big challenge that hinders its practical application in different areas.. Metal hydrides can store a large amount of hydrogen reversibly under good conditions (temperature, pressure, safety ...) compared to other storage modes (gaseous and liquid). In addition, these same materials are used as negative electrode in Nickel-Metal Hydride batteriesIn the first part of this thesis, Ti-Fe alloys were synthesized using mechanical alloying (MA) under argon atmosphere at room temperature, with different ball to powder weight ratio and at different milling times. In order to determine the optimal parameters of the elaboration the metallic composite were investigated using different techniques such as X-ray diffraction, scanning electron microscopy (EDS support), chronopotentiometry, chronoamperometry and cyclic voltammetry,In the second part, the metallic compounds, TiFe+4%MWNTs, TiFe0.95-xMx, TiFe0.90M0.10 and TiFe0.90Mn0.05V0.05 (x=0.05, 0.15) (M : Mn or V), which are used as the negative electrode material for Ni-MH secondary batteries, were synthesized by mechanical alloying according to optimal parameters, previously determined.The effect of MWNT addition, the Mn and/or V partial substitution for Fe and the excess of titanium on the structural, morphological and electrochemical parameters such as activation, electrochemical discharge capacity, reversibility, cycle life time and hydrogen diffusion coefficient were investigated.The redox properties of the electrodes such as the Nernst potential and the exchange current density were studied based on Stern’s first law and the theoretical model of Bulter-Volmer.The electrochemical properties of studied samples show the best performance for TiFe+4% MWNTs alloy. Indeed, this alloy presents a rapid activation (1st cycle) and a best discharge capacity (266 mAhg-1) with a reversibility remaining unchanged
Boulin, Pierre. "Expérimentation et modélisation du transfert d'hydrogène à travers des argiles de centre de stockage de déchets radioactifs". Phd thesis, Grenoble INPG, 2008. http://www.theses.fr/2008INPG0086.
Gases will be generated by corrosion of high radioactive waste containers in deep geological repositories. A gas phase will be generated. Gas pressure will build up and penetrated the geological formation. If gases do not penetrate the geological barrier efficiently, the pressure build up may create a risk of fracturation and of creation of preferential pathways for radionuclide migration. The present work focuses on Callovo-Oxfordian argillites characterisation. An experiment, designed to measure very low permeabilities, was used with hydrogen/helium and analysed using the Dusty Gas Model. Argillites close to saturation have an accessible porosity to gas transfer that is lower than 0,1% to 1% of the porosity. Analysis of the Knudsen effect suggests that this accessible network should be made of 50 nm to 200 nm diameter pores. The permeabilities values were integrated to an ANDRA operating model. The model showed that the maximum pressure expected near the repository would be 83 bar
Boulin, Pierre. "Expérimentation et Modélisation du Transfert d'hydrogène à travers des argiles de centre de stockage de déchets radioactifs". Phd thesis, Grenoble INPG, 2008. http://tel.archives-ouvertes.fr/tel-00331826.
Zhao, Weigang. "Synthèse et caractérisation de matériaux carbonés microporeux pour le stokage de l'hydrogène". Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0093/document.
This thesis describes the preparation, the characterisation and the performances in terms of hydrogen storage capacity of activated carbons designed for such application. The objective was to develop materials that might be able to meet or approach the storage capacity targeted by the US Department of Energy for 2015, i.e. 5.5 wt. % with respect to the whole storage system. With this aim in view, the researches reported here focused on: (1) investigation and understanding of experimental conditions for preparing such adsorbents; (2) optimization of their porous texture for hydrogen storage; (3) correlations between hydrogen storage capacity and textural parameters (surface area, pore volumes and pore size distributions); (4) investigation of materials doping by nitrogen and metal nanoparticles. Storage capacities of 6.6 % in weight with respect to adsorbent at 77K and 4 MPa on one hand, and of 1 wt. % at 298K and 20 MPa on the other hand, were obtained in the present thesis, among the highest reported so far in the open literature
Angers, Benjamin. "Simulations de fuites d'hydrogène en provenance d'un réservoir de stockage à haute pression : dispersion et conséquences de l'allumage". Thèse, Université du Québec à Trois-Rivières, 2006. http://depot-e.uqtr.ca/1944/1/000135772.pdf.
Shah, Virenkumar. "Propriétés interfaciales contrôlant la sécurité du stockage géologique des gaz acides". Pau, 2008. http://www.theses.fr/2008PAUU3015.
Acid gas geological storage is a process under which acid gas (CO2, H2S) is injected in a geological formation and thus stored away from the atmosphere for a long time (hundreds of years). It is a promising process to reduce CO2 atmospheric emissions and an alternative to the transformation of H2S into sulphur by the Claus process. In this process, the acid gas buoyantly rises to the top of the formation and accumulates beneath the caprock, a low permeable medium imbibed with water. This thesis investigates the interfacial properties involved in capillary failure of the caprock: water/acid gas interfacial tension (IFT) and caprock’s water-wettability. It presents the first ever systematic IFT and contact angle measurements under storage conditions (up to 150 bar and 120°C) with H2S-rich acid gases, as well as a model to predict IFTs between water and non-polar or slightly-polar compounds. Water/H2S IFT decreases with increasing pressure and levels off at around 9-10 mN/m at high pressure and temperature (T ≥ 70°C, P > 120 bar). However, wettability alteration due to the presence of dense acid gas is limited in the case of natural and model substrates typically present in the caprock, except in the case of mica, which exhibits pronounced alteration in the presence of H2S. These properties have a strong impact on various quantities of practical interest in geological storage, such as the maximum injection and storage pressure and potential storage capacity of a given formation. These quantities are significantly lowered in the case of H2S-rich gas as compared to CH4 and even CO2; they should be carefully determined when planning an acid gas geological storage operation
Tantchou, Yakam Guy. "Modélisation en cyclage-fluage du comportement mécanique d'un liner thermoplastique collapsé utilisé dans les réservoirs de stockage d'hydrogène gazeux". Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2017. http://www.theses.fr/2017ESMA0018/document.
Hyperbaric hydrogen storage vessels of type IV are encountering success for portable applications of fuel cell. During their use, these cylindric containers undergo repeated fill in/fill out cycles of H2-gaz. Under specific fillout conditions, an emerging detachment between the sealing inner layer (liner) and the composite wall, can be observed. This layer debonding also called collapse may limit the pressure release rate of H2-vessels or increase the residual gas pressure prescribed to avoid collapse.Experimental studies have been conducted by Air Liquide at vessel scale to identify some parameters responsible for the collapse onset. But the high cost of these studies and the complexity of the operating conditions makes the use of numerical tools necessary. That led to a numerical modeling approach. The main goal in the numerical approach is to model the cyclic mechanical response of a collapsed liner under fatigue – creep loadings.In this thesis, the purpose was to develop a mechanical constitutive law able to predict the cyclic deformation of a collapsed liner subjected to hydrogen pressure cycles.The liner was subjected to several environment variations due to: (i) the presence of residual water into the liner after initial hydraulic vessel tests, (ii) the temperature changes caused by the hydrogen compression/expansion, and (iii) the hydrogen diffusion/saturation. So, a preliminary work consisted in investigating the influence of each environmental factor on the polyamide 6 mechanical response. This first step allowed to outline a loading frame at laboratory scale that preserved main characteristics of the collapse phenomenon. Characterization tests on tensile specimens revealed that the liner could be modelled by a non linear viscoelastic law written within the thermodynamic framework of the irreversible processes in small deformations, and coupled with the temperature. Minor changes were introduced to extend the model capacity to capture liner behavior effects during fatigue – creep. These changes had negative impact on the manual method of model calibration, and consequently required to develop a specific identification strategy. The identification performance was assessed in different isothermal frames through stress rate, stress level and temperature effects. Then, the calibrated model was validated by taking temperature gradients into account, firstly on a tensile specimen, secondly within a H2-vessel
Peu, Pascal. "La gestion des effluents d'élevage et la production d'hydrogène sulfuré, cas particulier de la méthanisation". Phd thesis, Université Rennes 1, 2011. http://tel.archives-ouvertes.fr/tel-00634913.
Villeneuve-Faure, Christina. "Étude par spectrométrie Raman des défauts créés par l'implantation d'hydrogène et d'hélium dans le silicium et le silicium - germanium". Toulouse 3, 2007. http://thesesups.ups-tlse.fr/3745/.
Acoustic and optical phonons are very sensitive probes to characterize the disorder produced in a crystal. Consequently, Raman/Brillouin spectroscopy was used to study ion implantation-induced defects. The interest of this study arises from the fact that only light ions (hydrogen and/or helium) were used to induce damage in a perfect silicon single crystal. Such implanted systems, also used in the production of microelectronics substrates, exhibit two mains advantages for basic research: They are ideal candidates to quantify defects and to characterize the crystal-amorphous transition, thanks to the weak amount of damage and hence to slow and progressive defects accumulation with increasing implanted dose. The formation of extended defects (He bubbles or H2 platelets), which introduce a well-controlled porosity in the materials. As the aim is to characterize atomic disorder, extended defects and implantation-induced stress, short-range probe optical and long-range probe acoustic phonons were both used. We evidenced the influence of the implanted species (hydrogen vs helium), of the co-implantation and the sequence of the co-implantation, of the substrate orientation on both the implantation damage (profile and point defect density) and strain. The crystal-amorphous transition was characterized, as well as the vibration modes related to extended defects. The results and methods validated in the case of pure silicon were extended to silicon-germanium alloys (Si1-xGex) as function of the chemical composition x
Chebab, Safa. "Elaboration et caractérisation de composés hydrurables types AB3 (A : terre rares, B : métal 3d) pour le stockage et la conversion d'hydrogène". Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1054/document.
The increasing energy demand is mainly supplied by fossil sources which had environmental drawback essentially greenhouse gas emission. Considered as an energy carrier, hydrogen has the huge advantage to be clean. Its storage in intermetallic compound leads too higher hydration capacities than liquid and compressed storage. In this work, LaCaMgNi9 quaternary type alloy has been synthesized, for the first time, by mechanical alloying in order to avoid the inherent difficulties of the fusion technique. The structural and morphological characterization of the obtained alloys were performed. Their hydrogen related properties were examined (solid-gas and electrochemical reactions) in order to study their performance as negative electrode material in Ni-MH batteries
Schaefer, Sébastien. "Effets du dopage d'adsorbants nanoporeux par des métaux ou des semi-métaux nanodispersés sur leurs performances en stockage d'hydrogène par sorption". Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0123/document.
In this PhD work, microporous carbonaceous materials decorated with metallic nanoparticles were developed in order to study the effect of nanodispersed metals on hydrogen sorption properties. Bio-sourced precursors such as sucrose, mimosa tannins or even rice straw have been used in order to promote eco-friendly, sustainable and innovating ways of synthesis. The use of hydrothermal pretreatment on tannins or sucrose allowed obtaining hydrochars that have been chemically or physically activated. Depending on synthesis parameters, these syntheses allowed to produce materials with controlled porosity. Then, the hydrogen adsorption properties of these materials were evaluated at ambient temperature as well as their textural properties. The main interest of this work was to propose a coupling between hydrogen sorption properties, from low to high pressure, and the textural properties. The textural properties were modelized using theoretical tools such as the DFT (Density Functionnal Theory). The use the different precursors and of decoration steps using supercritical carbon dioxide or hydrothermal synthesis, during which ones metallic or nitrogen containing precursors were used, allowed to obtain nickel, nitrogen or silicon doped materials without using harmful organic solvents. Finally, the decorrelation of the different adsorption contributions gave the possibility to detect and quantify the hydrogen fractions engaged in different processes such as physisorption, chemisorption and spillover. Polarized or enhanced physisorption was also detected using the same methods
Ngameni, Jiembou Joseph Rostand. "Caractérisation thermodynamique, microstructurale et cinétique d’alliages de palladium au contact de l’hydrogène : application aux procédés de purification par perméation gazeuse". Paris 11, 2010. http://www.theses.fr/2010PA112377.
Palladium-silver alloys are used in the industry for the purification of hydrogen. State-of-the-art materials still require optimization (i) to increase permeation flows ; (ii) to maintain performances on the long-term ; (iii) to reduce investment costs (development of thin membranes). To achieve these goals, it is necessary to measure in situ surface (H₂ dissociative chemisorption) and bulk (diffusion transport of atomic H) kinetic contributions. The kinetics of chemical (gas-phase) and electrochemical (electrolyte) hydrogen insertion have been compared. Electrochemical and chemical impedance diagrams have been obtained from “potential step” and from “pressure step” experiments. Rate constants of individual steps have been measured. Then, the insertion of gaseous hydrogen into a metallic membrane of known surface state (texture and roughness factor) and known volume microstructure (grain size distribution) has been investigated. Values of surface resistance and hydrogen diffusion coefficient have been measured with temperature. By measuring the impedance of membranes of different thicknesses, it has been shown that the surface step is rate-determining. Then, the surface roughness of a membrane has been increased by electrochemical deposition of palladium black. A membrane showing a reduced surface resistance has been prepared and a diffusion impedance diagram has been obtained for the first time for a gas phase experiment
Leiva, Daniel Rodrigo. "Étude de l'élaboration de nanocomposites à base de magnésium pour le stockage d'hydrogène par broyage à haute énergie et déformation plastique sévère". Grenoble 1, 2009. http://www.theses.fr/2009GRE10040.
Mg-based nanocrystalline alloys or nanocomposites are promising materials for hydrogen storage in the solid state, being more effective and safe storing media than pressurized or liquefied hydrogen. In this work, the synthesis and processing of theses materials by high-energy ball milling (HEBM) and severe plastic deformation (SPD) were studied. MgH2- and Mg2FeH6- based nanocomposites were prepared by reactive milling under hydrogen atmosphere using different conditions in order to clarify the effects of several processing parameters in the hydride synthesis. Beside this, the use of the SPD techniques of high-pressure torsion (HPT) and equal-channel angular extrusion (ECAP) was explored to compose processing routes for Mg-based reactive mixtures for hydrogen storage. The materials prepared by the different methods were characterized by structural analysis techniques as, among others, X-ray diffraction, optical microscopy, scanning and transmission electron microscopy. The desorption behavior was studied by differential scanning calorimetry and selected samples were submitted to H-sorption cycles for kinetic measurements. The correlation of the results for the different Mg-based systems has promoted a better control of the synthesis of the nanocomposites by reactive milling and also a better knowledge of the potential of use of the SPD techniques in the composition of processing routes aiming hydrogen storage applications
Song, Myoung-Youp. "Étude de la cinétique et des propriétés de stockage de l'hydrogène de l'alliage Mg₂Ni et de mélanges mécanochimiques Mg-Ni". Bordeaux 1, 1986. http://www.theses.fr/1986BOR10515.
Grigorova, Eli. "Préparation et caractérisation de matériaux composites à base de magnésium et de Mg2Ni : application pour le stockage de l'hydrogène". Bordeaux 1, 2005. http://www.theses.fr/2005BOR12961.
Girard, Grégory. "Etude de nouvelles formes de matériaux basés sur le magnésium pour le stockage réversible de grandes quantités d'hydrogène - Effet d'addition d'éléments de transition". Phd thesis, Université Joseph Fourier (Grenoble), 2009. http://tel.archives-ouvertes.fr/tel-00445767.
Wojcieszak, Robert. "Catalyseurs de nickel Supportés Préparés par la Méthode de l'Hydrazine Aqueuse. Propriétés Hydrogénantes et Stockage d'Hydrogène : Effet du Support. Effet de l'Ajout d'Argent". Nancy 1, 2006. http://docnum.univ-lorraine.fr/public/SCD_T_2006_0023_WOJCIESZAK.pdf.
We have studied Ni or NiAg nanoparticles obtained by the reduction of nickel salts (acetate or nitrate) by hydrazine and deposited by simple or EDTA-double impregnation on various supports (g-Al2O3, amorphous or crystallized SiO2, Nb2O5, CeO2 and carbon). Prepared catalysts were characterized by different methods (XRD, XPS, low temperature adsorption and desorption of N2, FTIR and FTIR-Pyridine, TEM, STEM, EDS, H2-TPR, H2-adsorption, H2-TPD, isopropanol decomposition) and tested in the gas phase hydrogenation of benzene or as carbon materials in the hydrogen storage at room temperature and high pressure. The catalysts prepared exhibited better dispersion and activity than classical catalysts. TOF's of NiAg/SiO2 or Ni/carbon catalysts were similar to Pt catalysts in benzene hydrogenation. Differences in support acidity or preparation method and presence of Ag as metal additive play a crucial role in the chemical reduction of Ni by hydrazine and in the final properties of the materials. Ni/carbon catalysts could store significant amounts of hydrogen at room temperature and high pressure (0. 53%/30 bars), probably through the hydrogen spillover effect
Lacroix, Elodie. "Développements de protocoles méthodologiques pour le monitoring géochimique appliqué à la détection de fuite d'hydrogène (H₂) à l'aplomb des sites de stockage souterrain". Electronic Thesis or Diss., Université de Lorraine, 2021. http://www.theses.fr/2021LORR0342.
Combined with the energy transition, underground H₂ storage is a storage solution for the energy. The research project named "Rostock'H" integrating this thesis work associated the University of Lorraine and Ineris to develop geochemical monitoring methods in order to analyze the risks and opportunities. This project aims to study the risks and opportunities of H₂ storage in salt caverns. The next goal is to be able to store H₂ in a volume of up to 1,000,000 m³ between 300 and 1,400 m deep. The development of an underground storage site involves controlling pre, syn and post-operational risks by geochemical monitoring methods. Colorless and odorless, H₂ is a volatile and explosive gas. A particular attention is therefore paid to the risks of subsurface leakage from these storage sites and to the metrology associated with this detection. This thesis work had three main objectives: (i) to experiment in-situ and continuous monitoring methods from dissolved gas injections on a dedicated experimental site, (ii) to determine the potential impacts of a leak in “soils” and “aquifers” with a modeled analysis of the geochemical behavior of H₂ and associated parameters, (iii) to establish recommendations and a monitoring strategy for existing or future underground storage sites to prevent potential H₂ leakages. Composed of a semi-confined aquifer from 13 m deep, this experimental site in the Paris Basin has several wells and equipments reaching the saturated and unsaturated zones. Oxidizing, oxygenated and moderately mineralized, the waters of this aquifer have an initial chemical composition belonging to the calcium bicarbonate facies with a slight alteration in nitrates and sulphates. Several steps were necessary to simulate and model a potential leak: - Preparation of the site and choice of the metrological systems that will be deployed - Establishment of the initial state of the site through the definition of a geochemical baseline from measurements of the piezometric level, physico-chemical parameters, analyzes of ionic species and dissolved gas measurements in a dedicated well by combining of the Raman and infrared spectroscopies - Co-injection of dissolved He and hydrogeological tracers to validate the experimental protocol of the H₂ injection and to allow a first analysis of the aquifer dynamics - Co-injection of dissolved H₂ and tracers selected according to the adapted protocol linked to the experience feedback from the He injection - Post-injection monitoring to determine the impacts and the kinetics of return in the initial state of the aquifer using in particular the monitoring system of dissolved gases by optical sensors. An initial concentration of H₂ dissolved at 1.78 mg.L-1 was injected under surface conditions for 2.5 hours into the aquifer. The migration of the dissolved H₂ plume as well as other gases initially present in the aquifer was monitored both by continuous method (Raman and infrared spectroscopies) and discontinuous measurements (partial degassing). A dynamic of H₂ transfer in the water table was observed up to 20 m downstream from the injection well: 0.6 mg.L⁻¹ at 5 m, 0.17 mg.L⁻¹ at 7 m then 1.8*10⁻³ mg.L⁻¹ of H₂ at 10 and 20 m during the first week. Following the addition of H₂(aq), the physico-chemistry of the aquifer was modified with an increase of pH, a decrease of redox potential and of the O₂(aq) concentration. From continuous measurements by Raman spectroscopy (at 7 m downstream the injection well), a 2D model was established on the basis of a mixed H₂ diffusion/advection process, assuming a single-channel flow in the aquifer. The experimental results acquired in this thesis work validate, over the long term, the metrological choices applied, with a detection limit of H₂ in aquifer lowered to 0.02 mg.L⁻¹. These results thus confirm the feasibility of monitoring dissolved H2 in shallow aquifers and highlight the potential impacts of leakages from underground storage reaching the surface
Jacquemet, Nicolas. "Durabilité des matériaux de puits pétroliers dans le cadre d'une séquestration géologique de dioxyde de carbone et d'hydrogène sulfuré". Phd thesis, Université Henri Poincaré - Nancy I, 2006. http://tel.archives-ouvertes.fr/tel-00084391.