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Ji-cheng Zhao - One of the best experts on this subject based on the ideXlab platform.
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methods for Phase Diagram Determination
2007Co-Authors: Ji-cheng ZhaoAbstract:Chapter 1. Introduction to Phase Diagrams (J.F. Smith). Chapter 2. The Role of Phase Transformation Kinetics in Phase Diagram Determination and Assessment (J-C. Zhao). Chapter 3. Correct and Incorrect Phase Diagram Features (H. Okamoto, T.B. Massalski). Chapter 4. Determination of Phase Diagrams Using Equilibrated Alloys (Y. Zhong Zhan et al.). Chapter 5. DTA and Heat-Flux DSC Measurements of Alloy Melting and Freezing (W.J. Boettinger et al.). Chapter 6. Application of Diffusion Couples in Phase Diagram Determination (A.A. Kodentsov et al.). Chapter 7. Phase Diagram Determination Using Diffusion Multiples (J-C. Zhao). Chapter 8. Application of Computational Thermodynamics to Rapidly Determine Multicomponent Phase Diagrams (Y. Austin Chang, Y. Yang). Chapter 9. Determination of Phase Diagrams with Reactive or Volatile Elements (C. Guminski). Chapter 10. Phase Diagram Determination of Ceramic Systems (D. Edwards). Chapter 11. Determination of Phase Diagrams Involving Order-Disorder Transitions (R. Kainuma et al.). Chapter 12. Determination of Phase Diagrams Involving Magnetic Transitions (I. Takeuchi, S.E. Lofland). Chapter 13. Determination of Pressure-Dependent Phase Diagrams (S.K. Saxena, Y. Wang). Chapter 14. The Determination of Phase Diagrams for Slag Systems (D. Gaskell). Chapter 15. Determination of Phase Diagrams for Hydrogen-Containing Systems (T.B. Flanagan, W. Luo). Chapter 16. Phase Diagram Determination of Semiconductor Systems (V.P. Zlomanov, A. Davydov).
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chapter seven Phase Diagram Determination using diffusion multiples
Methods for Phase Diagram Determination, 2007Co-Authors: Ji-cheng ZhaoAbstract:Publisher Summary This chapter introduces a novel diffusion-multiple approach with examples. Using a hot isostatic pressing process, one can put several pieces of metals together to form several diffusion couples and triples in a single “diffusion multiple” to determine isothermal sections of several systems. The key considerations and steps in making good diffusion multiples are discussed in the chapter to stress the importance of sample preparation. The analysis steps involving imaging and Phase identification, the electron probe microanalysis, and extraction of tie lines are also discussed in the chapter. It is shown that two plots, one composition profile (composition–distance plot) and one composition path (composition–composition plot), are essential for reliable interpretation of the experimental results obtained from very concentrated areas of diffusion multiples. The chapter concludes discussing the practices used to reduce the chances of errors. By following the many recommendations specified in the chapter, one can determine Phase Diagrams with high efficiency while maintaining high quality.
S Pellet-rostaing - One of the best experts on this subject based on the ideXlab platform.
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An instrumented microfluidic tool for complex fluid Phase Diagram Determination: Inline and real-time exploration of solvent extraction
2015Co-Authors: T. Theisen, J. Rey, C. Penisson, A. Wilk, V. Kokoric, N. Verplanck, Sandrine Dourdain, B. Mizaikoff, J. Duhamet, S Pellet-rostaingAbstract:Liquid-liquid extraction, i.e. control of the reversible transfer of cations between Phases, is a core chemical process for metal purification and recycling. The objective of the “REE-CYCLE” project (Rare Earth Element reCYCling with Low harmful Emissions) is to develop the fundamental understanding of complex fluid processing in order to innovate environmentally friendly, economically competitive processes. The presented work on micro-solvent-extraction takes this approach beyond the state-of-the-art: An instrumented and computer-controlled microfluidic device is described, enabling the first steps towards fast measurement of the free energy of ion transfer between complex fluids. Continuous screening of a manifold parameter set, including e.g. multi-component Phase composition, pH, temperature, will be enabled by integra-ting inline, real-time measurements into a robotized lab-on-a-chip. Miniaturized spectro-scopic and sensing methods will allow automated characterization of kinetics/thermody-namics, partition coefficients, chemical potential differences and constituent’s activity coefficients. First results of the microfluidic device, compared to batch mode assays, are presented concerning temperature and pH variation. Examples are shown on N,N,N′,N′-tetraoctyl-3-oxapentane-1,5-diamide (TODGA) reverse micelles diluted in dodecane for lanthanide extraction in the presence of iron. Partition coefficients and kinetics data for different parameters are addressed and resulting pathways explored to enhance separation and selectivity. First data on solvent activity coefficient measurements will also be presented, giving insight on molecule aggregation, constituents’ chemical potentials and solvent vapour pressure.
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An instrumented microfluidic tool for complex fluid Phase Diagram Determination: Enabling in-line and real-time screening of solvent extraction processes
2015Co-Authors: Johannes Theisen, J. Rey, C. Penisson, A. Wilk, V. Kokoric, N. Verplanck, Sandrine Dourdain, B. Mizaikoff, J. Duhamet, S Pellet-rostaingAbstract:1 Scientific and technological background: Solvent extraction of metal ions and circular economy If Richard Feynman is often cited as a pioneer in Nanosciences, one should also cite Glenn Seaborg, 1951's Nobel prize in chemistry who stated in 1980 in a visionary conference that: « In the future, chemistry will be called upon to extend our natural resources of copper, lead, zinc, and other non-ferrous metals by making it possible to recover these metals more economically from low-grade ores or to recycle materials now discarded as waste » [1]. And indeed, rare earth elements as trivalent cations are absolutely irreplaceable for strong magnets, " energy-saving " light bulbs and high capacity batteries, amongst other applications. They are in fact not rare, just highly diluted in the earth crust. They are also chemically very similar. For these two reasons, their extraction and separation is a lengthy and very polluting process. Consequently, cost and environmental constraints led to the closure of most mining facilities in western countries over the past few decades, leading to today's quasi-monopoly of China which controls approximately 97% of the world's rare earth element market as per 2012 figures [2]. The same year, the first industrial recycling of rare earth elements by solvent extraction was started in Saint-Fons and La Rochelle, France, showing that supply autonomy, economical and ecological considerations are of importance in today's society. Following 2011 figures [3], Japan detains 300 kT of WEEE, corresponding to nearly three times the annual global production of rare earths. In order to recycle these ressources, solvent extraction processes need to be rendered ecologically friendly, and be rapidly adapted to each kind of urban mining material. Solvent extraction, i.e. control of the reversible transfer of cations between feed and extraction Phases, is a core chemical process for metal purification and recycling in hydrometallurgy. These processes are very complex chemical two-Phase systems, where slight changes in parameters may imply huge effects on the Phase behavior of the involved complex fluids. This may lead to so-called " third-Phase accidents " , representing huge financial losses for a production plant. The overall behavior of these complex fluids is analyzed in multi-dimensional Phase Diagrams, requiring several years of thorough analysis by techniques ranging from simple pH measurements to scattering techniques implying consequent instrumental and time efforts. Thus, solvent extraction process tweaking is frequently based on empirical data. The objective of the " REE-CYCLE " project (Rare Earth Element reCYCling with Low harmful Emissions) [4] is to develop the fundamental understanding involved in the process' complex fluids (both experimental and theoretical) in order to enable a quantum leap in process analysis and thereby rapidly innovating environmentally friendly and economically competitive processes. 2 Instrumented microfluidic device for complex fluid Phase Diagram exploration If extraction microfluidic devices have already been reported [5], the presented work takes this approach beyond the state of the art. Indeed, we will describe the instrumented and computer-controlled microfluidic device enabling the first steps towards simultaneous fast measurement of the free energy of mass transfer per ion pair between complex fluids. In the longer run, high-througput screening in this lab-on-a-chip tool, and complete automation and robotization of the experimental setup, will enable: 1) Rapid evaluation for innovative " green " processes issued of synthetic chemistry, 2) Benchmarking for numerical approaches and predictive theories, e.g. ienaics [6], 3) Process intensification and ecologilization regarding principles of green chemistry and circular economy. Screening of a manifold parameter set, including e.g. multi-component Phase composition, pH, temperature, etc., will be enabled by integrating inline and real-time measurements into a fully robotized system. Ultimately, the Les Rencontres Scientifiques d'IFP Energies nouvelles Microfluidics: from laboratory tools to process development Rueil-Malmaison, France, 4-5 November 2015 device will be designed to deliver continuous, in-line and real-time exploration of Phase Diagrams by combining several miniaturized spectroscopy and sensing methods for characterization of kinetic & thermodynamic time scales, partition coefficents of extraction, chemical potential differences and constituent activities, without user intervention. Here, we show first results of the microfluidic device (cf. Figure 1) and compare these with batch mode assays concerning temperature and pH variation. Examples will be shown on TODGA reverse micelles diluted in dodec-ane as model system, and extraction of five rare earth elements: La, Nd, Eu, Dy and Yb; in the presence of iron. Partition coefficients and kinetics data for different parameters will be addressed as well as pathways explored to enhance separation and selectivity. First data on solvent activity coefficient measurements will also be presented, giving insight on molecule aggregation, solvent chemical potentials and constituents' vapor pressures. Fig. 1. Microfluidic chip for solvent extraction with in-line measurement sites. Conclusions The microfluidic device stands as a first pillar of the REE-CYCLE project, enabling benchmarking for meso-scale modelling and numerical analysis, testing of newly synthesized extraction agents, and paving the way to assisted pertraction devices. On the longer time range, a semi-industrial prototype device for solvent extraction will be conceived gathering the results of all working groups. Furthermore, the microchemistry and-analysis activity is meant to be developed and extended beyond solvent extraction, involving research as well as industrial partners.
Van Fjj Frans Loo - One of the best experts on this subject based on the ideXlab platform.
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The diffusion couple technique in Phase Diagram Determination
Journal of Alloys and Compounds, 2001Co-Authors: Aa Alexander Kodentsov, Gf Giel Bastin, Van Fjj Frans LooAbstract:The diffusion couple technique is a valuable experimental approach in studying Phase relations in multicomponent systems. The use of different modifications of the method is illustrated by examples of Phase Diagram Determination in various ternary systems. It is also shown that a number of error sources may appear when multiPhase diffusion experiments are employed for constructing isothermal cross-sections. The difficulties connected with the concentration measurement at the interfaces and problems associated with the formation of a quasi-equilibrated diffusion zone are discussed. It is demonstrated that the efficiency of the diffusion couple technique is very high. However, in order to increase the reliability of the information obtained about a ternary Diagram, a combination of the diffusion methods with an investigation of selected alloys is desirable.
Cyril Aymonier - One of the best experts on this subject based on the ideXlab platform.
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A microfluidic approach for investigating multicomponent system thermodynamics at high pressures and temperatures
Lab on a Chip, 2014Co-Authors: Bruno Da Silva Pinho, Stéphane Girardon, Frédéric Bazer-bachi, Ghislain Bergeot, Samuel Marre, Cyril AymonierAbstract:In this work, we present a novel microfluidic-based approach for investigating the thermodynamics of multicomponent systems at high pressures and temperatures, such as determining miscibility Diagrams and critical coordinates of complex mixtures. The developed method is primarily based on (i) bubble and dew point detection through optical characterization and (ii) the use of a so-called dynamic stop-flow measurement mode for fast screening of the Diagram parameters, mainly P, T and composition. Our strategy was validated through the studies of model binary CO2-alkane mixtures. The obtained results were then compared to PREOS-calculated and literature data. We later applied this strategy for determining ternary and quaternary mixtures critical coordinates. This approach has equal accuracy compared to conventional high-pressure optical cell methods but allows for a much faster Phase Diagram Determination, taking advantage of improved heat and mass transfers on the microscale and of the dynamic stop-flow approach.
Daniel Topgaard - One of the best experts on this subject based on the ideXlab platform.
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Polarization transfer solid-state NMR for studying surfactant Phase behavior.
Langmuir, 2010Co-Authors: Agnieszka Nowacka, Parveen Choudhary Mohr, Jens Norrman, Rachel W. Martin, Daniel TopgaardAbstract:The Phase behavior of amphiphiles, e.g., lipids and surfactants, at low water content is of great interest for many technical and pharmaceutical applications. When put in contact with air having a moderate relative humidity, amphiphiles often exhibit coexistence between solid and liquid crystalline Phases, making their complete characterization difficult. This study describes a (13)C solid-state NMR technique for the investigation of amphiphile Phase behavior in the water-poor regime. While the (13)C chemical shift is an indicator of molecular conformation, the (13)C signal intensities obtained with the CP and INEPT polarization transfer schemes yield information on molecular dynamics. A theoretical analysis incorporating the effect of molecular segment reorientation, with the correlation time τ(c) and order parameter S, shows that INEPT is most efficient for mobile segments with τ(c) 10 μs and/or S > 0.5 under typical solid-state NMR experimental conditions. For liquid crystalline Phases, where τ(c) < 0.01 μs and 0 < S < 0.3, the observed CP and INEPT intensities serve as a gauge of S. The combination of information on molecular conformation and dynamics permits facile Phase Diagram Determination for systems with solid crystalline, solid amorphous, anisotropic liquid crystalline, and isotropic liquid (crystalline) Phases as demonstrated by experiments on a series of reference systems with known Phase structure. Three solid Phases (anhydrous crystal, dihydrate, gel), two anisotropic liquid crystalline Phases (normal hexagonal, lamellar), and two isotropic liquid crystalline Phases (micellar cubic, bicontinuous cubic) are identified in the temperature-composition Phase Diagram of the cetyltrimethylammonium succinate/water system. Replacing the succinate counterion with DNA prevents the formation of Phases other than hexagonal and leads to a general increase of τ(c).