Larrayoz Iriarte, Maria Angeles
Total activity: 87
Research group
FLUIDS - Fluids Engineering
Department
Department of Chemical Engineering
School
Barcelona School of Industrial Engineering (ETSEIB)
E-mail
m.angeles.larrayozupc.edu
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Scientific and technological production
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1 to 50 of 87 results
  • Evaluation of physical properties on a supercritical tertiary mixture using CFD

     Mekala, Samuel; Guardo Zabaleta, Alfredo de Jesús; Larrayoz Iriarte, Maria Angeles
    Conference on Supercritical Fluids and Their Applications
    Presentation's date: 2013-05
    Presentation of work at congresses

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    Crystallization of microparticulate pure polymorphs of active pharmaceutical ingredients using CO 2-expanded solvents  Open access

     Sala, S.; Córdoba, A.; Moreno Calvo, E.; Elizondo, Elisa; Muntó, M.; Rojas, P.E.; Larrayoz Iriarte, Maria Angeles; Ventosa, Nora; Veciana, Jaume
    Crystal growth and design
    Date of publication: 2012-04-04
    Journal article

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    The feasibility of the Depressurization of an Expanded Liquid Organic Solution (DELOS) method to process different active pharmaceutical ingredients (APIs) as finely divided powders with narrow particle size distribution, high crystallinity degree, high polymorphic purity, and free from residual solvent has been demonstrated. Cholesterol, acetylsalicylic acid (aspirin), naproxen, acetaminophen, and ibuprofen were chosen as model drugs. It has been demonstrated that the supersaturation ratio attained during crystallization from CO2-expanded solvents can be modulated through appropriate variations of process parameters  CO2 content and concentration of the initial solution. In view of the potential application that compressed fluidsbased technologies have in the pharmaceutical industry, a preliminary scalability study of the process in compliance with the constraints imposed by the Good Manufacturing Practices (GMP) specifications is presented herein

  • Continuous production of biodiesel using supercritical fluids: A comparative study between methanol and ethanol

     Santana Scotelari de Souza, Aline; Maçaira, José; Larrayoz Iriarte, Maria Angeles
    Fuel processing technology
    Date of publication: 2012-09
    Journal article

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  • Using CFD to estimate external mass transfer coefficients and intra-particle diffusional effects on the supercritical hydrogenation of sunflower oil

     Guardo Zabaleta, Alfredo de Jesús; Ramirez Rangel, Eliana; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    Date of publication: 2012-09-02
    Book chapter

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    Hydrogenation of vegetable oils is an important process in the food industry because of its widespread application to produce margarines, shortenings, and other food components. Supercritical technology has proven to be a reliable alternative to conventional hydrogenation process because not only the trans isomer levels can be reduced, but also offers a clean, economic and environmental friendly process. Computational Fluid Dynamics (CFD) modeling applied to the supercritical hydrogenation reaction can be useful in visualizing and understanding the mass transfer phenomena involved. CFD is applied to the study of the catalytic hydrogenation of sunflower oil in the presence of a supercritical solvent. A mix of sunflower oil, hydrogen and supercritical propane (used as a solvent) is the flowing fluid. Their transport properties at high pressure are incorporated within a CFD commercial code in order to estimate them online within the simulation process. A 2D CFD model of a single Pd-based catalyst pellet is presented. Intra-particle and surface concentration profiles and surface mass fluxes for all species present in the mixture (oil triglycerides and hydrogen) are obtained and compared against experimental results. Different temperatures, flow velocities and particle sizes are studied and external and internal mass transfer phenomena are analyzed. External mass transfer coefficients for hydrogen and oil triglycerides are obtained and a correlation for estimating them is presented.

  • Continuous production of biodiesel from vegetable oil using supercritical ethanol/carbon dioxide mixtures

     Santana Scotelari de Souza, Aline; Maçaira, José; Larrayoz Iriarte, Maria Angeles
    Fuel processing technology
    Date of publication: 2012-04
    Journal article

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  • Glycerol desorption from ion exchange and adsorbent resin using supercritical fluid technology: An optimization study

     Costa, A. E.; Santana Scotelari de Souza, Aline; Quadri, M.B; Machado, R.A.F; Recasens Baxarias, Francisco-javier; Larrayoz Iriarte, Maria Angeles
    Journal of supercritical fluids
    Date of publication: 2011-09
    Journal article

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    In this study, glycerol desorption from Purolite® PD206 resin was investigated using conventional and supercritical fluids (SCF) techniques. Untreated biodiesel was purified by dry washing using the resin and, after purification, the glycerol desorption was carried out using absolute ethanol under atmospheric conditions at different mass flows (10–30 g/min) or using ethanol-modified supercritical CO2 (1:3 molar ratio of ethanol:CO2), under a pressure of 140 bar, within a temperature range of 106–134ºC and with mass flow rates of 6–34 g/min. The results showed that ethanol is an efficient solvent for this process and that the supercritical desorption is much faster than conventional desorption process. Employing the Response Surface Methodology (RSM) it was found that temperature has the greatest effect on the resin regeneration time using supercritical fluids. Optimum conditions obtained were 106.1ºC and 21.9 g/min, in which the resin was regenerated in only 4.17 min.

  • Producción de hidrógeno a partir del reformado con vapor de dimetil éter utilizando monolitos catalíticos  Open access

     Ledesma Rodriguez, Cristian
    Defense's date: 2011-11-25
    Department of Chemical Engineering, Universitat Politècnica de Catalunya
    Theses

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    El modelo actual del consumo energético basado en la utilización de combustibles fósiles requiere un replanteamiento debido al agotamiento de éstos y a las emisiones de gases contaminantes que generan. La obtención de energía mediante la utilización de pilas de combustible se presenta como una alternativa prometedora dado su elevado rendimiento energético y que únicamente genera agua como subproducto. El tipo más sencillo de pila de combustible requiere de una fuente de oxígeno e hidrógeno. El primero puede extraerse del aire de forma sencilla, pero el hidrógeno debe generarse ya que no existe de forma aislada en la Tierra. Uno de los métodos con los que se obtiene una mayor cantidad de hidrógeno es mediante el reformado catalítico con vapor de un combustible derivado de la biomasa, el cual además es un método sostenible dado que no se generan nuevas emisiones a la atmósfera. En este trabajo se ha estudiado la producción de hidrógeno a través de la reacción catalítica y endotérmica del reformado con vapor del dimetil éter, producto que puede obtenerse a partir de la biomasa. Para ello se ha preparado y caracterizado mediante diferentes técnicas propias del estado sólido una serie de catalizadores soportados en estructuras monolíticas de cordierita que contienen diferentes óxidos inorgánicos como soporte y cobre, zinc, paladio o mezclas de éstos como fase activa. Se ha estudiado el comportamiento de los catalizadores monolíticos en la reacción de reformado con vapor del dimetil éter para evaluar su actividad, selectividad y estabilidad tanto en condiciones diluidas como en condiciones próximas a las de la industria. Asimismo se ha estudiado el mecanismo de la reacción mediante espectroscopía IR y la naturaleza de los centros activos de los catalizadores mediante espectroscopía fotoelectrónica de rayos X (XPS). El catalizador monolítico que ha mostrado un mejor comportamiento en términos de actividad, selectividad y estabilidad es el que contiene Cu y Zn como fase activa y óxido de zirconio. La presencia de especies reducidas de cobre favorece la formación de especies intermedias tipo formiato, que son las que evolucionan a dióxido de carbono. La presencia del zinc favorece la dispersión de las partículas de cobre, además de mejorar la selectividad hacia los productos de la reacción de reformado, hidrógeno y dióxido de carbono

    The current model of energy consumption based on the use of fossil fuels needs a change due to their exhaustion and their hazardous emissions to the atmosphere. Fuel cells are considered a promising alternative due to their high energy yield and only water is produced as a side product. The easiest type of fuel cell needs a source of oxygen and hydrogen. The first one can be extracted from air but the hydrogen must be produced since it does not exist as an isolated compound in Earth. One of the methods which a high amount of hydrogen is produced is by the steam reforming reaction of a biomass derived fuel, a sustainable method since no new emissions are generated. In this work, the production of hydrogen by the catalytic steam reforming of dimethyl ether (DME), a fuel that can be obtained from biomass, has been studied. Different catalysts supported on cordierite monolithic structures have been prepared and characterized by different techniques. These catalysts contain different inorganic oxides as a support and copper, zinc, palladium or mixtures of them as active phase. The performance of these catalysts in terms of activity, selectivity and stability in the DME steam reforming reaction has been studied under diluted conditions or using pure mixtures, simulating industrial conditions. Moreover, the reaction mechanism has been studied by IR spectroscopy and the nature of the active sites of the catalysts has been studied by X-ray photoelectron spectroscopy (XPS). The catalytic monolith that showed the best performance in terms of activity, selectivity and stability was the one that contains copper and zinc as active phase and zirconia oxide as a support. The presence of copper-reduced species favours the formation of formate intermediates, which evolves to carbon dioxide. The presence of zinc favours the dispersion of copper particles and improves the selectivity towards the reforming products, hydrogen and carbon dioxide.

  • Biodiesel production using supercritical methanol/carbon dioxide mixtures in a continuous reactor

     Maçaira, José; Santana Scotelari de Souza, Aline; Recasens Baxarias, Francisco-javier; Larrayoz Iriarte, Maria Angeles
    Fuel (Guildford)
    Date of publication: 2011-03-01
    Journal article

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    Fatty acid methyl esters (biodiesel) were produced by the transesterification of triglycerides with compressed methanol (critical point at 240 C and 81 bar) in the presence of solid acids as heterogeneous catalyst (SAC-13). Addition of a co-solvent, supercritical carbon dioxide (critical point at 31 C and 73 bar), increased the rate of the supercritical alcohols transesterification, making it possible to obtain high biodiesel yields at mild temperature conditions. Experiments were carried out in a fixed bed reactor, and reactions were studied at 150–205 C, mass flow rate 6–24 ml/min at a pressure of 250 bar. The molar ratio of methanol to oil, and catalyst amount were kept constant (9 g). The reaction temperature and space time were investigated to determine the best way for producing biodiesel. The results obtained show that the observed reaction rate is 20 time faster than conventional biodiesel production processes. The temperature of 200 C with a reaction time of 2 min were found to be optimal for the maximum (88%) conversion to methyl ester and the free glycerol content was found below the specification limits.

  • Vegetable Oils Hydrogenation Technology in Supercritical Fluids for Food Applications: Characterization of Hydrogenated Products.

     Santana Scotelari de Souza, Aline
    Defense's date: 2009-07-17
    Department of Chemical Engineering, Universitat Politècnica de Catalunya
    Theses

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  • Use of the supercritical fluid technology for the preparation of nanostructured hybrid materials and design of the interface  Open access  awarded activity

     García González, Carlos Alberto
    Defense's date: 2009-12-11
    Department of Chemical Engineering, Universitat Politècnica de Catalunya
    Theses

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    Los materiales compuestos nanoestructurados son considerados una opción prometedora para la concepción de materiales multifuncionales. Sin embargo, la falta habitual de interacción entre los componentes orgánicos e inorgánicos en los materiales híbridos nanoestructurados comporta unas propiedades macroscópicas anisotrópicas que limitan su uso. Por ello, se hace necesario el diseño de la interfase formada entre los componentes mencionados a fin de mejorar sus prestaciones. En esta Tesis Doctoral se ha optado por el uso de dióxido de carbono supercrítico (scCO2) para la modificación superficial de nanopartículas inorgánicas y para la preparación de materiales híbridos nanoestructurados. Estos procesos supercríticos, diseñados como sostenibles, se proponen como sustitutos de técnicas convencionales que empleen disolventes orgánicos. El tratamiento superficial de nanopartículas de dióxido de titanio (TiO2) con octiltrietoxisilano se ha empleado como sistema de estudio para evaluar el uso de recubrimientos de alcoxisilanos bifuncionales como promotores de adhesión de partículas inorgánicas nanométricas. El scCO2 se emplea como disolvente del alcoxisilano para la silanización del TiO2. También se han llevado a cabo estudios fundamentales de solubilidad de octiltrietoxisilano en CO2 y de la cinética del proceso de silanización del TiO2. La modulación de las propiedades fisicoquímicas del scCO2 con la presión y la temperatura permite el control de las características del recubrimiento con silano. El proceso de silanización supercrítico se ha extendido a diferentes sistemas alcoxisilano-nanopartículas inorgánicas. Asimismo, se ha evaluado la tecnología de scCO2 para la preparación de materiales híbridos nanoestructurados que contengan nanopartículas inorgánicas silanizadas. El tratamiento superficial de las nanopartículas favorece la distribución homogénea de éstas en el material híbrido y mejora la interacción relleno-matriz orgánica. Se han procesado matrices biopoliméricas de interés en ingeniería tisular, compuestas de ácido poliláctico o la mezcla iv polimetilmetacrilato/policaprolactona, con adiciones de nanopartículas de TiO2 o hidroxiapatita, respectivamente. Para su procesado, se ha empleado scCO2 como no-disolvente utilizando la técnica Particles from a Compressed Anti-Solvent (PCA). Además, se han preparado partículas híbridas formadas por una mezcla lipídica de aceite de ricino hidrogenado y glicerilmonoestearato con adiciones de TiO2 y cafeína, con posibles aplicaciones en cremas para uso tópico. Estas partículas sólidas lipídicas se han obtenido usando la técnica Particles from Gas Saturated Solutions (PGSS) que emplea scCO2 como soluto. Por último, el proceso de silanización supercrítico se ha ensayado para materiales híbridos complejos multiescalados. Se han procesado materiales de base cemento empleando un proceso supercrítico de carbonatación-silanización en dos etapas. Primero, el cemento se carbonata de manera acelerada usando scCO2 como agente de carbonatación. Este cemento, ya carbonatado, se somete, finalmente, a un tratamiento hidrofóbico mediante silanización supercrítica, para su posible aplicación en confinamiento de residuos peligrosos en ambientes húmedos o como material de construcción duradero.

    Nowadays, society is asking for a global changing in the way of manufacturing goods in a more sustainable manner. Indeed, the weight of the classical factors (cost, quality, appearance) influencing the acceptance of a certain good in the market have currently changed. Manufacturing requirements and regulations concerning environment protection (e.g., resource consumption, sustainability, toxicity, CO2 footprint, recycling potential) and quality features (e.g., product guarantees, durability against aggressive environments, corporate vision) are aspects of increasing concern. The competitive position of a company is influenced by seizing the opportunities and challenges and by managing the risks that the changeable market has. As a consequence, the industry is continuously looking for smart and innovative solutions for the design and manufacturing of materials with novel properties and increased added value, and for the production of materials already existing in the market in a more efficient manner. Nanostructured hybrid composites have emerged as a promising class of innovative materials for many industrial sectors (e.g., energy, optoelectronics, biomedicine, cosmetics). The multicomponent composition of these materials provides them with unique properties arising from the synergistic combination of the characteristics of their individual components structured at the nanolevel. Nevertheless, in numerous hybrid materials, the lack of coupling or bonding between the components often leads to anisotropic macroscopic properties, limiting their use. Hence, the interaction at the interphase between hybrid components must be properly engineered to enhance materials properties. In this PhD Thesis, the quest for sustainable and environmentally friendly processes led to the use of supercritical carbon dioxide (scCO2) for both the surface modification of nanometric inorganic particles and the preparation of nanostructured hybrid materials. These processes are designed for the replacement of conventional methods using organic solvents. vi Bifunctional alkoxysilane molecules, acting as adhesion promoters, are, herein, investigated for the surface modification of nanometric inorganic particles. The surface treatment of titanium dioxide (TiO2) nanoparticles with octyltriethoxysilane is taken as the model system for study. In terms of processing, scCO2 is used as the solvent of choice for alkoxysilanes for the surface modification of TiO2. Fundamental studies on the solubility of the used silane in CO2 in the pressure range 8-18 MPa at two different temperatures (318 and 348 K) and on the kinetics of the TiO2 silanization process are performed. For the scCO2-aided silanization process, studies are conducted to ascertain the effects and interactions of the operating variables on the properties of the final material. Results show that the tunable physicochemical properties of scCO2 with pressure and temperature (e.g., density, solvation power) allows the engineering control of the characteristics of the silane coating. Examples of the extension of the application of the supercritical silanization process to other sets of alkoxysilanes and inorganic nanoparticles are also presented. The preparation of hybrid materials including silanized inorganic nanoparticles and organic matrices is further tested using scCO2 technology. Surface treated nanoparticles are used to facilitate the homogeneous distribution of the nanoparticles within the matix and to improve the inorganic filler-organic matrix interaction. Biopolymeric matrices of either poly(L-lactic acid) (L-PLA) or the blend poly(methylmethacrylate)/poly(ε-caprolactone) (PMMA/PCL) loaded with nanometric titanium dioxide or hydroxyapatite, respectively, are prepared. To obtain these hybrid materials, scCO2 is employed as an anti-solvent, using the Particles from a Compressed Anti-Solvent (PCA) technique. Studies are performed to pursue the effect of the processing conditions on the morphology of the precipitated hybrid materials. The resulting material, obtained in the form of fibers, has suitable properties for its potential application in tissue engineering. In a different system, hybrid particles composed of a lipidic matrix (hydrogenated castor oil/glyceryl monostearate) loaded with silanized titanium dioxide and caffeine are prepared. The Particles from Gas Saturated Solutions (PGSS) technique, assisted by the use of scCO2 as a solute, is employed for the production of these solid lipid particles. The obtained hybrid material is evaluated concerning the drug carrier and release ability and the UV-shielding capacity. The UV-light protection and photoaging prevention capacity of the lipid-based hybrid material provide excellent properties for the use of these particles in the formulation of sunscreens and pharmaceutical dermal products. vii Finally, the possibility of extending the supercritical silane treatment to multiscale complex hybrid materials is assessed. The technology based on the use of scCO2 is presented for the two-step carbonation-silanization process of cement-based materials. In the first step, the carbonation of cement is accelerated using scCO2 as the carbonation agent. The effects of the cement formulation and process operation conditions on the microstructure and physicochemical properties of carbonated samples are evaluated. The carbonation process is followed by the hydrophobic treatment of the carbonated samples using a supercritical silanization method. The surface modification of carbonated cement with octyltriethoxysilane confers water repellence to the material. The carbonation-silanization process is scheduled and integrated to mitigate the consumption of raw materials and the use of facilities.

  • Vegetable Fat Hydrogenation in Supercritical-Fluid Solvents: Melting Behaviour by DSC and NMR

     Santana, A; Fernández, X; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    Journal of supercritical fluids
    Date of publication: 2008-10
    Journal article

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  • Hidrogenation reactions in SC solvents

     Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier; Zgarni, S
    Date of publication: 2008-12
    Book chapter

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  • Trans-free hydrogenation of vegetable fat in vapor fase supercritical modified CO2

     Santana Scotelari de Souza, Aline; Mayorga, M J; Huguet, A; Pina, B; Recasens Baxarias, Francisco-javier; Larrayoz Iriarte, Maria Angeles
    AIChE Annual Meeting
    Presentation of work at congresses

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  • Sunflower oil hydrogenation on Pd in supercritical solvents: Kinetics and selectivities

     Santana, A; Larrayoz Iriarte, Maria Angeles; Ramirez, E; Nistal, J; Recasens Baxarias, Francisco-javier
    Journal of supercritical fluids
    Date of publication: 2007-07
    Journal article

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  • CFD modeling on external mass transfer and intra-particle diffusional effects on the supercritical hydrogenation of sunflower oil

     Guardo Zabaleta, Alfredo de Jesús; Casanovas, M; Ramírez, E; Recasens Baxarias, Francisco-javier; Magaña, I; Martínez, D; Larrayoz Iriarte, Maria Angeles
    Chemical engineering science
    Date of publication: 2007-09
    Journal article

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  • CFD studies on particle-to-fluid mass and heat transfer in packed beds: Free convection effects in supercritical fluids

     Guardo Zabaleta, Alfredo de Jesús; Coussirat Nuñez, Miguel Gustavo; Recasens Baxarias, Francisco-javier; Larrayoz Iriarte, Maria Angeles; Escaler Puigoriol, Francesc Xavier
    Chemical engineering science
    Date of publication: 2007-09
    Journal article

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  • Computational Fluid Dynamics Studies in Heat and Mass Transfer Phenomena in Packed Bed Extraction and Reaction Equipment: Special Attention to Supercritical Fluids Technology  Open access

     Guardo Zabaleta, Alfredo de Jesús
    Defense's date: 2007-03-01
    Department of Chemical Engineering, Universitat Politècnica de Catalunya
    Theses

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    El entendimiento de los fenómenos de transferencia de calor y de masa en medios porosos implica el estudio de modelos de transporte de fluidos en la fracción vacía del medio; este hecho es de fundamental importancia en muchos sistemas de Ingeniería Química, tal como en procesos de extracción o en reactores catalíticos. Los estudios de flujo realizados hasta ahora (teóricos y experimentales) usualmente tratan al medio poroso como un medio efectivo y homogéneo, y toman como válidas las propiedades medias del fluido. Este tipo de aproximación no tiene en cuenta la complejidad del flujo a través del espacio vacío del medio poroso, reduciendo la descripción del problema a promedios macroscópicos y propiedades efectivas. Sin embargo, estos detalles de los procesos locales de flujo pueden llegar a ser factores importantes que influencien el comportamiento de un proceso físico determinado que ocurre dentro del sistema, y son cruciales para entender el mecanismo detallado de, por ejemplo, fenómenos como la dispersión de calor, la dispersión de masa o el transporte entre interfaces.La Dinámica de Fluidos Computacional (CFD) como herramienta de modelado numérico permite obtener una visión mas aproximada y realista de los fenómenos de flujo de fluidos y los mecanismos de transferencia de calor y masa en lechos empacados, a través de la resolución de las ecuaciones de Navier - Stokes acopladas con los balances de materia y energía y con un modelo de turbulencia si es necesario. De esta forma, esta herramienta permite obtener los valores medios y/o fluctuantes de variables como la velocidad del fluido, la temperatura o la concentración de una especie en cualquier punto de la geometría del lecho empacado.El objetivo de este proyecto es el de utilizar programas comerciales de simulación CFD para resolver el flujo de fluidos y la transferencia de calor y de masa en modelos bi/tri dimensionales de lechos empacados, desarrollando una estrategia de modelado aplicable al diseño de equipos para procesos de extracción o de reacción catalítica. Como referencia se tomaran procesos de tecnología supercrítica debido a la complejidad de los fenómenos de transporte involucrados en estas condiciones, así como a la disponibilidad de datos experimentales obtenidos previamente en nuestro grupo de investigación. Estos datos experimentales se utilizan como herramienta de validación de los modelos numéricos generados, y de las estrategias de simulación adoptadas y realizadas durante el desarrollo de este proyecto.

    An understanding of the heat and mass transfer phenomena in a porous media implies the study of the fluid transport model within the void space; this fact is of fundamental importance to many chemical engineering systems such as packed bed extraction or catalytic reaction equipment. Experimental and theoretical studies of flow through such systems often treat the porous medium as an effectively homogeneous system and concentrate on the bulk properties of the flow. Such an approach neglects completely the complexities of the flow within the void space of the porous medium, reducing the description of the problem to macroscopic average or effective quantities. The details of this local flow process may, however, be the most important factor influencing the behavior of a given physical process occurring within the system, and are crucial to understanding the detailed mechanisms of, for example, heat and mass dispersion and interface transport.Computational Fluid Dynamics as a simulation tool allows obtaining a more approached view of the fluid flow and heat and mass transfer mechanisms in fixed bed equipment, through the resolution of 3D Reynolds averaged transport equations, together with a turbulence model when needed. In this way, this tool permit to obtain mean and fluctuating flow and temperature values in any point of the bed. The goal of this project is to use commercial available CFD codes for solving fluid flow and heat and mass transfer phenomena in two and three dimensional models of packed beds, developing a modeling strategy applicable to the design of packed bed chemical reaction and extraction equipment. Supercritical extraction and supercritical catalytic reaction processes will be taken as reference processes due to the complexity of the transport phenomena involved within this processes, and to the availability of experimental data in this field, obtained in the supercritical fluids research group of this university. The experimental data priory obtained by our research group will be used as validation data for the numerical models and strategies dopted and followed during the developing of the project.

  • Differential Scanning Calorimetryc studies of the hydrogenated products in SCFs fluids

     Santana Scotelari de Souza, Aline; Fernandez Francos, Xavier; Ramirez Rangel, Eliana; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    5th International Symposium on High Pressure Processes Technology and Chemical Engineering
    Presentation of work at congresses

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  • Using CFD to estimate external mass transfer coefficients and intra-particle diffusional effects on the supercritical hydrogenation of sunflower oil

     Guardo Zabaleta, Alfredo de Jesús; Casanovas, M; Ramirez Rangel, Eliana; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    5th International Symposium on High Pressure Processes Technology and Chemical Engineering
    Presentation's date: 2007-06-26
    Presentation of work at congresses

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  • Intraparticle Diffusion Mechanisms in Supercritical Sunflower Oil Hydrogenation on Pd/C Catalyst

     Ramirez Rangel, Eliana; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    AICHE journal
    Date of publication: 2006-04
    Journal article

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  • CFD study on particle-to-fluid heat transfer in fixed bed reactors: Convective heat transfer at low and high pressure

     Guardo Zabaleta, Alfredo de Jesús; Coussirat Nuñez, Miguel Gustavo; Recasens Baxarias, Francisco-javier; Larrayoz Iriarte, Maria Angeles; Escaler Puigoriol, Francesc Xavier
    Chemical engineering science
    Date of publication: 2006-02
    Journal article

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  • ¿Es posible obtener margarinas más saludables?

     Ramirez Rangel, Eliana; Santana, A; Guardo Zabaleta, Alfredo de Jesús; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    CTC alimentación
    Date of publication: 2006-06
    Journal article

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  • AGL2006-05156 MINIMIZACION DEL RIESGO EN LA HIDROGENACION SUPERCRITICA DE ACEITES VEGETALES UTILIZANDO CO2 CON COSOLVENTE

     Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    Participation in a competitive project

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  • Supercritical Fluid Extraction of Fat from Animal Skin

     Generó, N; Masferrer, M; Santana Scotelari de Souza, Aline; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    8th International Symposium on Supercritical Fluids
    Presentation of work at congresses

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  • Effect of Triacylglycerols Distribution on the Melting Behaviour of the Hydrogenated Products in SC Fluids

     Santana Scotelari de Souza, Aline; Ramirez Rangel, Eliana; Recasens Baxarias, Francisco-javier; Larrayoz Iriarte, Maria Angeles
    8th Conference on Supercritical Fluids and Their Applications
    Presentation of work at congresses

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  • Effect of Triglyceride Distribution and Crystallization on the Melting Behavior of the Hydrogenated Products in Several SCFs Fluids

     Santana Scotelari de Souza, Aline; Fernández, X; Ramirez Rangel, Eliana; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    8th International Symposium on Supercritical Fluids
    Presentation of work at congresses

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  • Entrainer Selection for Vegetable Oil Hydrogenation in SC CO2

     Cama, J; Ramirez Rangel, Eliana; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    8th International Symposium on Supercritical Fluids
    Presentation of work at congresses

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  • Influence of the turbulence model in CFD modeling of wall-to-fluid heat transfer in packed beds

     Guardo Zabaleta, Alfredo de Jesús; Coussirat Nuñez, Miguel Gustavo; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier; Egusquiza Estevez, Eduardo
    Chemical engineering science
    Date of publication: 2005-03
    Journal article

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  • Contribution to the study of heterogeneous catalytic reactions in SCFs: Hydrogenation of sunflower oil in Pd catalysts at single-phase conditions

     Ramirez Rangel, Eliana
    Defense's date: 2005-12-19
    Department of Chemical Engineering, Universitat Politècnica de Catalunya
    Theses

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  • Using CFD simulations to estimate properties of a supercritical binary mixture

     Guardo Zabaleta, Alfredo de Jesús; Oliver, A; Larrayoz Iriarte, Maria Angeles
    The 10th Meeting on Supercritical Fluids: Reactions, Materials and Natural Product Processing
    Presentation of work at congresses

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  • Flow and heat transfer simulation in a packed bed with supercritical solvent: CFD modeling of free convection effects

     Guardo Zabaleta, Alfredo de Jesús; Larrayoz Iriarte, Maria Angeles; Recasens Garcia, Francesc
    Flow and heat transfer simulation in a packed bed with supercritical solvent: CFD modeling of free convection effects
    Presentation of work at congresses

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  • Study of meeting behaviour of hydrogenated vegetable oils in supercritical propane

     Guardo Zabaleta, Alfredo de Jesús; Santana Scotelari de Souza, Aline; Ramirez Rangel, Eliana; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    The 10th Meeting on Supercritical Fluids: Reactions, Materials and Natural Product Processing
    Presentation of work at congresses

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  • Hidrogenación catalítica de aceite de girasol en fluido supercrítico y su interés en la indústria alimentaria

     Guardo Zabaleta, Alfredo de Jesús; Larrayoz Iriarte, Maria Angeles; Ramirez Rangel, Eliana; Recasens Baxarias, Francisco-javier; Santana Scotelari de Souza, Aline
    2a Reunión de Expertos en Tecnologías de Fluidos Comprimidos (Red Flucomp)
    Presentation of work at congresses

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  • CFD flow and mass transfer simulation in a packed bed with supercritical solvent: preliminary results

     Guardo Zabaleta, Alfredo de Jesús; Coussirat Nuñez, Miguel Gustavo; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    The 10th Meeting on Supercritical Fluids: Reactions, Materials and Natural Product Processing
    Presentation of work at congresses

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  • Sunflower Oil Hydrogenation on Pd/C in SC Propane in a Continuous Recycle Reactor

     Ramirez Rangel, Eliana; Recasens Baxarias, Francisco-javier; FERNANDEZ, M; Larrayoz Iriarte, Maria Angeles
    AICHE journal
    Date of publication: 2004-07
    Journal article

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  • CFD flow and heat transfer in non-regular packings for fixed bed equipment design.

     Guardo Zabaleta, Alfredo de Jesús; Coussirat Nuñez, Miguel Gustavo; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier; Egusquiza Estevez, Eduardo
    Industrial & engineering chemistry research
    Date of publication: 2004-06
    Journal article

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  • PROCESO DE HIDROGENACIÓN PARCIAL DE TRIGLICÉRIDOS INSATURADOS EN FASE VAPOR A ALTA PRESIÓN Y REACTOR PARA LA REALIZACIÓN DE DICHO PROCESO / High Pressure Process of Partial Hydrogenation of un-saturated triglycerides in gas phase

     Ramirez Rangel, Eliana; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier; Hernán-Pérez, Silvia Camps; Fernández, Mónica Garza
    Date of request: 2004-09-01
    Invention patent

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    Proceso de hidrogenación parcial de triglicéridos insaturados en fase vapor a alta presión y reactor para la realización de dicho proceso.

    Se describe un proceso de hidrogenación de aceites vegetales sobre paladio, en fase vapor homogénea, que emplea una mezcla de triglicéridos, hidrógeno y un solvente gaseoso a alta presión.

    El proceso se realiza en un reactor de flujo mezclado consistente en un lecho fijo de partículas de catalizadores con flujo radial o bien en un reactor monolito, ambos con pequeño tamaño de partícula y baja pérdida de carga. El efecto de mezcla perfecta en ambos se consigue por recirculación de la mezcla reactante.

    Empleando alta turbulencia en el reactor y pequeño tamaño de partícula del catalizador, se consiguen contenidos del isómero C18:1 trans inferiores al 3,5% en peso.

  • Gas-Phase Sunflower Oil Hydrogenation in High Pressure Propane: Preliminary Kinetics in an Internal-Recycle CSTR

     Ramirez Rangel, Eliana; Oliveira, A S; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    European Congress of Chemical Engineering
    Presentation of work at congresses

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  • Regular packing types for CFD simulation of SCF extraction and reaction equipment

     Guardo Zabaleta, Alfredo de Jesús; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    6th International Symposium on Supercritical Fluids
    Presentation of work at congresses

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  • Pd-Catalised Hydrogenation of Sunflower Oil in SC Propane: Design of Experiments in a well Mixed Continuous Reactor

     Ramirez Rangel, Eliana; Recasens Baxarias, Francisco-javier; Fernández, M; Larrayoz Iriarte, Maria Angeles
    6th International Symposium on Supercritical Fluids
    Presentation of work at congresses

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  • Sunflower Oil Hydrogenation In SCF In A Continuous Reactor: Preliminary Experimental Results

     Ramirez Rangel, Eliana; Larrayoz Iriarte, Maria Angeles
    4th International Symposium on High Pressure Technology and Chemical Engineering
    Presentation of work at congresses

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  • Short Compilation of Published Rate-of-reaction Data for Hydrogenations in Supercritical Fluids

     Ramirez Rangel, Eliana; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    Chemical engineering and technology
    Date of publication: 2002-09
    Journal article

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  • PROCEDIMIENTO DE OBTENCIÓN DE FRACCIONES DE LÍPIDOS CON DIÓXIDO DE CARBONO PRESURIZADO A PARTIR DE LANA O LANOLINA

     Recasens Baxarias, Francisco-javier; Larrayoz Iriarte, Maria Angeles
    Date of request: 2002-06-06
    Invention patent

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  • Hydrogenation reactions in SC Solvents

     Zgarni, S; Ramirez Rangel, Eliana; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    Exploratory Workshop on Supercritical Fluids as Active MEdia: Fundamentals and Applications
    Presentation of work at congresses

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  • Hydrogenation Of Organic Compounds In Sc Solvents: Preliminary Data On Catalytic Rates

     Ramirez Rangel, Eliana; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    IV Brazilian Meeting on Supercritical Fluids
    Presentation of work at congresses

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  • Procedimiento de obtención de fracciones de lípidos con dióxido de carbono presurizado a partir de lana o lanolina

     Recasens Baxarias, Francisco-javier; Larrayoz Iriarte, Maria Angeles; Termens, Joseph Maria Bayona; Serrabasa, Pilar Erra; Moldovan, Zaharie; Domínguez, Carmen Fernández; Jover Comas, Eric
    Date of request: 2001-06-11
    Invention patent

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  • Catalyst Reactivation Using Supercritical CO2

     Stüber, F; Abauroudi, K J Trabelsi; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier
    Industrial & engineering chemistry research
    Date of publication: 2000-01
    Journal article

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  • Waterless wool cleaning process with supercritical carbon dioxide: extractor modeling and optimisation

     Trabelsi, Fakher; Larrayoz Iriarte, Maria Angeles; Recasens Baxarias, Francisco-javier; Trabelsi, F; Luc, J -C; Miquel, J; Capilla, M
    Date of publication: 2000-05
    Book chapter

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