<div>Adsorbent technology is widely used in many industrial applications including waste heat recovery, water purification, and atmospheric revitalization in confined habitations. Astronauts depend on adsorbent-based systems to remove metabolic carbon dioxide (CO₂) from the cabin atmosphere; as NASA prepares for the journey to Mars, engineers are redesigning the adsorbent-based system for reduced weight and optimal efficiency. These efforts hinge upon the development of accurate, predictive models, as simulations are increasingly relied upon to save cost and time over the traditional design-build-test approach. Engineers rely on simplified models to reduce computational cost and enable parametric optimizations. Amongst these simplified models is the axially dispersed plug-flow model for predicting the adsorbate concentration during flow through an adsorbent bed. This model is ubiquitously used in designing fixed-bed adsorption systems. The current work aims to improve the accuracy of the axially dispersed plug-flow model because of its wide-spread use. This dissertation identifies the critical model inputs that drive the overall uncertainty in important output quantities then systematically improves the measurement and prediction of these input parameters. Limitations of the axially dispersed plug-flow model are also discussed, and recommendations made for identifying failure of the plug-flow assumption.</div><div><br></div><div>An uncertainty and sensitivity analysis of an axially disperse plug-flow model is first presented. Upper and lower uncertainty bounds for each of the model inputs are found by comparing empirical correlations against experimental data from the literature. Model uncertainty is then investigated by independently varying each model input between its individual upper and lower uncertainty bounds then observing the relative change in predicted effluent concentration and temperature (<i>e.g.</i>, breakthrough time, bed capacity, and effluent temperature). This analysis showed that the LDF mass transfer coefficient is the largest source of uncertainty. Furthermore, the uncertainty analysis reveals that ignoring the effect of wall-channeling on apparent axial dispersion can cause significant error in the predicted breakthrough times of small-diameter beds.</div><div><br></div><div>In addition to LDF mass transfer coefficient and axial-dispersion, equilibrium isotherms are known to be strong lever arms and a potentially dominant source of model error. As such, detailed analysis of the equilibrium adsorption isotherms for zeolite 13X was conducted to improve the fidelity of CO₂ and H₂O on equilibrium isotherms compared to extant data. These two adsorbent/adsorbate pairs are of great interest as NASA plans to use zeolite 13X in the next generation atmospheric revitalization system. Equilibrium isotherms describe a sorbent’s maximum capacity at a given temperature and adsorbate (<i>e.g.</i>, CO₂ or H₂O) partial pressure. New isotherm data from NASA Ames Research Center and NASA Marshall Space Flight Center for CO₂ and H₂O adsorption on zeolite 13X are presented. These measurements were carefully collected to eliminate sources of bias in previous data from the literature, where incomplete activation resulted in a reduced capacity. Several models are fit to the new equilibrium isotherm data and recommendations of the best model fit are made. The best-fit isotherm models from this analysis are used in all subsequent modeling efforts discussed in this dissertation.</div><div><br></div><div>The last two chapters examine the limitations of the axially disperse plug-flow model for predicting breakthrough in confined geometries. When a bed of pellets is confined in a rigid container, packing heterogeneities near the wall lead to faster flow around the periphery of the bed (<i>i.e.</i>, wall channeling). Wall-channeling effects have long been considered negligible for beds which hold more than 20 pellets across; however, the present work shows that neglecting wall-channeling effects on dispersion can yield significant errors in model predictions. There is a fundamental gap in understanding the mechanisms which control wall-channeling driven dispersion. Furthermore, there is currently no way to predict wall channeling effects a priori or even to identify what systems will be impacted by it. This dissertation aims to fill this gap using both experimental measurements and simulations to identify mechanisms which cause the plug-flow assumption to fail.</div><div><br></div><div>First, experimental evidence of wall-channeling in beds, even at large bed-to-pellet diameter ratios (<i>d</i>_bed/<i>d</i>_p=48) is presented. These experiments are then used to validate a method for accurately extracting mass transfer coefficients from data affected by significant wall channeling. The relative magnitudes of wall-channeling effects are shown to be a function of the adsorption/adsorbate pair and geometric confinement (<i>i.e.</i>, bed size). Ultimately, the axially disperse plug-flow model fails to capture the physics of breakthrough when nonplug-flow conditions prevail in the bed.</div><div><br></div><div>The final chapter of this dissertation develops a two-dimensional (2-D) adsorption model to examine the interplay of wall-channeling and adsorption kinetics and the adsorbent equilibrium capacity on breakthrough in confined geometries. The 2-D model incorporates the effect of radial variations in porosity on the velocity profile and is shown to accurately capture the effect of wall-channeling on adsorption behavior. The 2-D model is validated against experimental data, and then used to investigate whether capacity or adsorption kinetics cause certain adsorbates to exhibit more significant radial variations in concentration compared than others. This work explains channeling effects can vary for different adsorbate and/or adsorbent pairs—even under otherwise identical conditions—and highlights the importance of considering adsorption kinetics in addition to the traditional <i>d</i>_bed/<i>d</i>_p criteria.</div><div><br></div><div>This dissertation investigates key gaps in our understanding of fixed-bed adsorption. It will deliver insight into how these missing pieces impact the accuracy of predictive models and provide a means for reconciling these errors. The culmination of this work will be an accurate, predictive model that assists in the simulation-based design of the next-generation atmospheric revitalization system for humans’ journey to Mars.</div>

Ce travail vise à évaluer les performances de matériaux à base de silice et à rationaliser leur synthèse en fonction des propriétés d’adsorption recherchées (capacité et/ou sélectivité) en combinant des approches expérimentales et la modélisation de dynamique moléculaire. Ces matériaux devaient idéalement présenter une capacité d’adsorption CO2 mais également une sélectivité CO2 /CH4 élevées. Les différentes étapes de ce travail ont été :- la synthèse et la fonctionnalisation des matériaux de silice,- leur caractérisation texturale et chimique,- la détermination des capacités d’adsorption du CO2, de leur sélectivité CO2/CH 4 ,- les caractérisations par différentes techniques spectroscopiques et microscopiques des échantillons pour essayer de localiser l’adsorption du CO2 et mesurer sa mobilité,- l’identification microscopique par modélisation moléculaire des facteurs physico-chimiques influant sur l’adsorption préférentielle du CO2 et sa diffusivité dans le matériau hôte ainsi que sur le rôle du caractère hydrophile/hydrophobe du matériau de silice par le biais de sa fonctionnalisation.Ces objectifs ont nécessité la préparation de matériaux à surfaces spécifiques élevées par le biais d’un procédé sol-gel simple. Ces matériaux ont été modifiés afin d’obtenir un taux de fonctionnalisation par des groupements -CH3 suffisant pour modifier le caractère hydrophile du matériaux tout en conservant une surface spécifique suffisante. L’influence de la taille des pores a également été sondée.Les capacités d’adsorption des gaz sous pression ont été réalisées pour les gaz purs mais également sur des mélanges CO2/CH4 dans différentes proportions. La sélectivité CH 4 /CO 2 , souvent estimée à partir des isothermes des corps purs et/ou la méthode IAST, a dans ce cas été déterminée à partir de la mesure directe des isothermes des mélanges de gaz. Il est apparu que l’eau joue un rôle crucial sur les capacité et sélectivités d’adsorption. Ce paramètre est l’un de ceux qui a été étudié à travers les simulations de dynamiques moléculaires. L’influence de l’introduction de groupements hydrophobes a également été exploré.Les résultats obtenus par dynamique moléculaire sont dans l’ensemble en bon accord avec les données expérimentales. Ces deux approches parallèles expérience/théorie ont mis en évidence la sélectivité de l’un des matériaux pour des applications où l’effluent gazeux est peu chargé en CO 2 . / This work aims to evaluate the performance of silica-based materials and to rationalize their synthesis according to their desired adsorption properties (capacity and/or selectivity) by combining experimental approaches and the management of the molecular animal. These materials are ideally suited for CO2 adsorption capacity but also CO2/ CH4 selectivity. The different stages of this work were:- the synthesis and functionalization of the silica materials,- their textural and chemical characterization,- the determination of CO2 adsorption capacities, of their CO2/ CH4 selectivity.- the characterizations by various spectroscopic and microscopic techniques of tests to try to locate the adsorption of CO2 and to measure its mobility,- microscopic identification by the factor of physic-Factors influence the preferential adsorption of CO2 and its diffusivity in the role of hydrophilic / hydrophobic character in silica by functional.These objectives required the preparation of high specific surface materials through a simple sol-gel process. These materials have been modified in order to obtain a degree of functionalization with -CH3 groups sufficient to modify the hydrophilic nature of the material while maintaining a sufficient specific surface area. The influence of pore size was also probed.The adsorption capacities of the gases under pressure were carried out for pure gases but also on CO2/ CH4 mixtures in different proportions. The CH4/ CO2 selectivity, often estimated from the pure body isotherms and / or the IAST method, was in this case determined from the direct measurement of the isotherms of the gas mixtures. It has become apparent that water plays a crucial role in adsorption capacity and selectivity. This parameter is one of those studied through molecular dynamics simulations. The influence of the introduction of hydrophobic groups has also been explored.The results obtained by molecular dynamics are on the whole in good agreement with the experimental data. These two parallel experience / theory approaches have highlighted the selectivity of one of the materials for applications where the gaseous effluent is little loaded with CO2.

No description available.

The work described in this thesis focuses on the effects that adsorption processes on catalytic surfaces pose in controlling key steps that can affect and control reaction pathways. To that, the development of Nuclear Magnetic Resonance (NMR) relaxometry methods and the comparison with traditional catalytic was performed with a series of C5 and C6 unsaturated hydrocarbons on two different alumina supports, γ- and θ-Al2O3. The developed techniques were applied in the study of liquid phase selective hydrogenation of citral on 5% Pt/SiO2. Infrared (IR) spectroscopy, volumetric adsorption isotherms, dynamic isotherms via a Tapered Element Oscillating Microbalance (TEOM), temperature programmed desorption (TPD) as well as 13C T1 NMR and 1H 2D T1-T2 relaxometry methods were employed. Energies of adsorption as a function of coverage were obtained via adsorption isotherms and the particular surface adsorbate interactions were described with IR spectroscopy. For example, 1-pentyne showed the strongest interaction with the alumina (94 kJ mol-1) while 1-pentene presented a weaker interaction (46 kJ mol-1) on θ-Al2O3. Desorption energies obtained from TPD ranged 85 – 130 kJ mol-1, irrespective of the adsorbate. Reactivity of the aluminas was captured with TPD, TEOM and NMR relaxometry. Interaction of adsorbates with hydrocarbon occurred predominantly on weak adsorption sites. 13C NMR T1 relaxometry provided in addition atom-specific adsorbate-adsorbent interaction strengths, showing the molecular geometry of adsorption, and applied in co adsorption measurements. The selective hydrogenation of citral as a model α,β-unsaturated aldehyde and the effect of different solvents on the activity and product distribution was studied at 298 and 373 K. A series of polar protic, polar aprotic and non polar solvents was investigated. Results showed higher initial reaction rates in non polar solvents but higher selectivities towards desired products on polar protic solvents. Solvent used also affected by product formation. The strong variations in reaction rates and selectivities reported were related with adsorbate catalyst interactions, as well as solvent reactant interactions. For example, adsorption isotherms showed that ethanol notably reduced the adsorption capacity of citral as compared with hexane, related with the rate differences observed. ATR-IR measurements indicated solvent citral interactions were solely present in polar protic solvents in line with higher yields of geraniol and nerol. Finally, 13C T1 NMR and 1H 2D T1-T2 correlation experiments determined that the geometry of adsorption of citral, influenced by solvent, affected product selectivity, and that product adsorption affected selectivity and deactivation.

Tesis por compendio / [ES] El objetivo de la presente tesis es el de desarrollar y utilizar técnicas basadas en la fotónica de baja frecuencia, como la radiofrecuencia, las microondas y los infrarrojos, para monitorizar de forma no destructiva procesos utilizados en la industria agroalimentaria, desde el punto de vista de la termodinámica irreversible. Estudiar los distintos fenómenos que ocurren durante la operación de deshidratación de patata mediante el secado con aire caliente combinado con microondas, utilizando la termografía infrarroja para monitorizar los perfiles de temperatura superficial que presenta la muestra, la espectrofotometría en el rango de las microondas y la termodinámica irreversible para modelizar el proceso. Desarrollar un sistema de monitorización de la congelación de la carne de pollo, que permita obtener datos del proceso a tiempo real y de forma no invasiva mediante la espectrofotometría en el rango de la radiofrecuencia y la termografía infrarroja. A su vez, con esos datos se modelizará el comportamiento del producto a lo largo del proceso de congelación, utilizando los principios de la termodinámica irreversible para estimar los distintos fenómenos que ocurren. Desarrollar una herramienta de predicción de los distintos estados del agua y la sacarosa durante el proceso de caramelizado de manzanas, basada en las propiedades dieléctricas obtenidas mediante la espectrofotometría en el rango de las microondas. Diseñar y desarrollar un sensor basado en las propiedades dieléctricas en el rango de la radiofrecuencia, capaz de monitorizar en tiempo real y de forma no invasiva con el medio las cinéticas de liberación de compuestos encapsulados en matrices de alginato en un medio líquido. Utilizando este nuevo sensor se pueden modelizar y estudiar las cinéticas de liberación y utilizarse para diseñar la encapsulación de compuestos. / [CA] L'objectiu de la present tesi és el de desenvolupar i utilitzar tècniques basades en la fotònica de baixa freqüència, com ara la radiofreqüència, les microones i els infrarojos, per monitoritzar de forma no destructiva processos utilitzats a la indústria agroalimentària, des del punt de vista de la termodinàmica irreversible. Estudiar els diferents fenòmens que ocorren durant l'operació de deshidratació de patata mitjançant l'assecat amb aire calent combinat amb microones, utilitzant la termografia infraroja per monitoritzar els perfils de temperatura superficial que presenta la mostra, l'espectrofotometria al rang de les microones i la termodinàmica irreversible per modelitzar el procés. Desenvolupar un sistema de monitorització de la congelació de la carn de pollastre, que permeti obtenir dades del procés a temps real i de manera no invasiva mitjançant l'espectrofotometria al rang de la radiofreqüència i la termografia infraroja. Alhora, amb aquestes dades es modelitzarà el comportament del producte al llarg del procés de congelació, utilitzant els principis de la termodinàmica irreversible per estimar els diferents fenòmens que ocorren. Desenvolupar una eina de predicció dels diferents estats de l'aigua i la sacarosa durant el procés de caramel·litzat de pomes, basada en les propietats dielèctrics obtingudes mitjançant l'espectrofotometria al rang de les microones. Dissenyar i desenvolupar un sensor basat en les propietats dielèctrics al rang de la radiofreqüència, capaç de monitoritzar en temps real i de forma no invasiva amb el medi les cinètiques d'alliberament de compostos encapsulats en matrius d'alginat en un medi líquid. Utilitzant aquest sensor nou es poden modelitzar i estudiar les cinètiques d'alliberament i utilitzar-se per dissenyar l'encapsulació de compostos. / [EN] The objective of this thesis is to develop and use techniques based on low-frequency photonics, such as radiofrequency, microwaves and infrared, to non-destructively monitor processes used in the agri-food industry, from the point of view of irreversible thermodynamics. To study the different phenomena that occur during the potato dehydration operation by drying with hot air combined with microwaves, using infrared thermography to monitor the surface temperature profiles of the sample, spectrophotometry in the microwave range and thermodynamics. irreversible to model the process. Develop a monitoring system for the freezing of chicken meat, which allows data to be obtained from the process in real time and non-invasively through spectrophotometry in the radiofrequency range and infrared thermography. In turn, with these data, the behavior of the product will be modeled throughout the freezing process, using the principles of irreversible thermodynamics to estimate the different phenomena that occur. To develop a prediction tool for the different states of water and sucrose during the candying process of apples, based on the dielectric properties obtained by spectrophotometry in the microwave range. Design and develop a sensor based on dielectric properties in the radiofrequency range, capable of monitoring in real time and non-invasively with the medium the release kinetics of compounds encapsulated in alginate matrices in a liquid medium. Using this new sensor, release kinetics can be modeled and studied and used to design the encapsulation of compounds. / The authors acknowledge the financial support from THE SPANISH MINISTERIO DE ECONOMÍA, INDUSTRIA Y COMPETITIVIDAD, Programa Estatal de I+D+i orientada a los Retos de la Sociedad AGL2016- 80643-R, Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER). Juan Ángel Tomás-Egea wants to thank the FPI Predoctoral Program of the Universitat Politècnica de València for its support. This paper is part of the I+D+i PID2020-116816RB-I00 project, funded by MCIN/ AEI/10.13039/501100011033. / Tomás Egea, JÁ. (2022). Fotónica aplicada a la monitorización de procesos y al desarrollo de sensores en la industria agroalimentaria [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/182292 / TESIS / Compendio

The preparation of a new group of functionalized conjugated polymer networks has been described based on spontaneous quaternization polymerization of ethynylpyridines with bis(bromomethyl)arenes. The networks consisted of polyacetylene chains with pyridyl and pyridiniumyl pendants cross-linked with -CH2(arylene)CH2- links. The variation of the ratio of monomer and quaternization agent in the feed modified the ratio of pyridyl and pyridiniumyl groups in the networks (pyridyl/pyridiniumyl ratios from 0 to 1.32). The networks did not exhibit a permanent microporosity that could be confirmed by nitrogen adsorption at 77 K. Nevertheless, all networks were active in capture of CO2 at 293 K (up to 0.73 mmol CO2/g, 750 Torr). It has been hypothesized that CO2 capture reflected formation of a temporary porous texture of the networks through conformational changes of the network segments enabled by the segments mobility at room temperature. The preparation of functionalized conjugated polymer networks with permanent micro/mesoporosity (SBET up to 667 m2 /g) has been described that was based on chain coordination copolymerization of acetylenic monomers. The copolymerization of 1,4-diethynylbenzene or 4,4'-diethynylbiphenyl with mono or diethynylbenzenes bearing NO2 or CH2OH groups has been demonstrated as...

Tesis por compendio / [ES] El mercado de bebidas vegetales está experimentando un crecimiento constante debido a la creciente demanda de productos de origen vegetal. Dentro de este mercado, la bebida de almendra, perteneciente al grupo de las oleaginosas, destaca por su alto contenido en nutrientes, compuestos fenólicos y sus propiedades antioxidantes. Por otra parte, la generación masiva de residuos y subproductos por parte de la industria alimentaria representa uno de los mayores desafíos a nivel global. De acuerdo con la Comisión Europea, aproximadamente se desperdicia un 13% de la producción alimentaria mundial, equivalente a 366 millones de toneladas dentro de la Unión Europea. La industria alimentaria ha estado trabajando en la implementación de los Objetivos de Desarrollo Sostenible (ODS) adoptados por las Naciones Unidas en 2015, con especial atención en el ODS 12, que promueve la producción responsable y sostenible. Este objetivo busca prevenir el desperdicio de alimentos, revalorizar residuos y promover la economía circular como parte de la Agenda 2030. En este contexto, el objetivo general de la presente tesis fue estudiar las posibilidades de revalorización del subproducto resultante del proceso de obtención de la bebida vegetal de almendra. Determinar las propiedades fisicoquímicas, tecnológicas y funcionales de la materia prima. Evaluar el efecto de la deshidratación (secado con aire caliente y liofilización) sobre las propiedades fisicoquímicas, el contenido de componentes bioactivos, su bioaccesibilidad y su influencia sobre la microbiota. Finalmente, se consideró la posibilidad de obtener un producto deshidratado con probióticos. La consecución de este objetivo se abordó desde tres enfoques que se presentan en tres capítulos en los que se ha estructurado el apartado de resultados. En el primer capítulo se evaluó el impacto del secado por aire caliente a 60 °C y 70 °C y de la liofilización, sobre las propiedades tecno-funcionales del bagazo de almendra. Se analizaron las curvas de secado y las isotermas de sorción. Luego, se evaluó el efecto del almacenamiento a temperatura ambiente y en condiciones aceleradas de los polvos obtenidos por ambos métodos de secado; durante 6 meses, se monitoreó el crecimiento microbiológico, la acidez, el índice de peróxidos, la capacidad antioxidante y el contenido de polifenoles. Finalmente, se evaluó la idoneidad del polvo de bagazo de almendra como sustituto en la elaboración de productos de panadería, concretamente galletas. Tanto el secado por aire caliente como la liofilización resultaron ser operaciones adecuadas para estabilizar el bagazo de almendra. Ambos métodos de secado, combinados con un triturado adecuado, proporcionaron polvos con propiedades favorables para su uso en la industria alimentaria. En relación con la actividad antirradical, no se presentaron diferencias significativas entre las muestras deshidratadas, si bien el contenido en fenoles totales fue mayor en las muestras liofilizadas. En cuanto al almacenamiento durante 6 meses, al finalizar dicho periodo se observó un aumento en la capacidad antirradical, así como en el contenido de fenoles totales, especialmente notable en las muestras secadas por aire caliente y sometidas a almacenamiento acelerado. Los valores de acidez e índice de peróxido aumentaron considerablemente durante el almacenamiento acelerado, posiblemente debido a la descomposición de los ácidos grasos. Finalmente, se evaluó la idoneidad del polvo de bagazo de almendra como ingrediente sustitutivo en la elaboración de productos de panadería. Los resultados mostraron la idoneidad del subproducto para ser utilizado como sustituto de la harina de trigo en la elaboración de galletas ya que proporcionó un producto de textura adecuada con mayor contenido en fibra y componentes con capacidad antirradical. / [CA] El mercat de begudes vegetals està experimentant un creixement constant a causa de la demanda creixent de productes d'origen vegetal. Dins aquest mercat, la beguda d'ametlla, pertanyent al grup de les oleaginoses, destaca pel seu alt contingut en nutrients, compostos fenòlics i propietats antioxidants. D'altra banda, la generació massiva de residus i subproductes per part de la indústria alimentària representa un dels desafiaments més grans a nivell global. D'acord amb la Comissió Europea, aproximadament es desaprofita un 13% de la producció alimentària mundial, equivalent a 366 milions de tones dins de la Unió Europea. La indústria alimentària ha estat treballant en la implementació dels Objectius de Desenvolupament Sostenible (ODS) adoptats per les Nacions Unides el 2015, amb especial atenció a l'ODS 12, que promou la producció responsable i sostenible. Aquest objectiu cerca prevenir el malbaratament d'aliments, revalorar residus i promoure l'economia circular com a part de l'Agenda 2030. En aquest context, l'objectiu general de la present tesi va ser estudiar les possibilitats de revaloració del subproducte resultant del procés d'obtenció de la beguda vegetal d'ametlla. Determinar les propietats fisicoquímiques, tecnològiques i funcionals de la matèria primera. Avaluar l'efecte de la deshidratació (assecat amb aire calent i liofilització) sobre les propietats fisicoquímiques, el contingut de components bioactius, la bioaccessibilitat i la influència sobre la microbiota. Finalment, es va considerar la possibilitat d'obtenir un producte deshidratat amb probiòtics. La consecució d'aquest objectiu es va abordar des de tres enfocaments que es presenten en tres capítols en el que s'ha estructurat l'apartat de resultats. En el primer capítol es va avaluar l'impacte de l'assecat per aire calent a 60 °C i 70 °C, i de la liofilització, sobre les propietats tecno-funcionals del bagàs d'ametlla. Es van analitzar les corbes d'assecat i les isotermes de sorció. Després, es va avaluar l'efecte de l'emmagatzematge a temperatura ambient i en condicions accelerades de les pols obtingudes pels dos mètodes d'assecat; durant 6 mesos, es va monitoritzar el creixement microbiològic, l'acidesa, l'índex de peròxids, la capacitat antioxidant i el contingut de polifenols. Finalment, es va avaluar la idoneïtat de la pols de bagàs d'ametlla com a substitut en l'elaboració de productes enfornats, concretament galetes. Tant l'assecat per aire calent com la liofilització van resultar ser operacions adequades per estabilitzar el bagàs d'ametlla. Ambdós mètodes d'assecat, combinats amb un triturat adequat, van proporcionar pols amb propietats favorables per al seu ús a la indústria alimentària. En relació amb l'activitat antirradical, no es van presentar diferències significatives entre les mostres deshidratades, si bé el contingut en fenols totals va ser més gran en les mostres liofilitzades. En relació amb l'emmagatzematge durant 6 mesos, en finalitzar aquest període es va observar un augment en la capacitat antirradical, així com en el contingut de fenols totals, especialment notable a les mostres assecades per aire calent i sotmeses a emmagatzematge accelerat. Els valors d'acidesa i índex de peròxid van augmentar considerablement durant l'emmagatzematge accelerat, possiblement degut a la descomposició dels àcids grassos. Finalment, es va avaluar la idoneïtat de la pols de bagàs d'ametlla com a ingredient substitutiu en l'elaboració de productes enfornats. Els resultats van mostrar la idoneïtat del subproducte per ser utilitzat com a substitut de la farina de blat en l'elaboració de galetes ja que va proporcionar un producte de textura adequada amb més contingut en fibra i components amb capacitat antirradical. / [EN] The vegetable beverage market is experiencing steady growth due to the increasing demand for products of vegetable origin. Within this market, the almond beverage, which belongs to the oilseed group, stands out for its high content of nutrients, phenolic compounds and antioxidant properties. On the other hand, the massive generation of waste and by-products by the food industry represents one of the major global challenges. According to the European Commission, approximately 13% of the world's food production is wasted, equivalent to 366 million tonnes within the European Union. The food industry has been working on the implementation of the Sustainable Development Goals (SDGs) adopted by the United Nations in 2015, with a particular focus on SDG 12, which promotes responsible and sustainable production. This goal aims to prevent food waste, revalue waste and promote the circular economy as part of the 2030 Agenda. In this context, the general objective of this thesis was to study the possibilities of revaluing the by-product resulting from the process of obtaining almond plant-based beverage. To determine the physicochemical, technological and functional properties of the raw material. Evaluate the effect of dehydration (hot air drying and freeze-drying) on the physicochemical properties, the content of bioactive components, their bioaccessibility and their influence on the microbiota. Finally, the possibility of obtaining a dehydrated product with probiotics was considered. The achievement of this objective was approached through three perspectives presented in three chapters, structuring the results section accordingly. In the first chapter, the impact of hot air drying at 60 °C and 70 °C and freeze-drying on the techno-functional properties of almond bagasse was evaluated. Drying curves and sorption isotherms were analysed. Then, the effect of storage at room temperature and under accelerated conditions of the obtained powders by both drying methods was evaluated; over a period of 6 months, microbiological growth, acidity, peroxide index, antioxidant capacity, and polyphenol content were monitored. Finally, the suitability of almond bagasse powder as a substitute in the production of bakery products, specifically biscuits, was assessed. Both hot air drying and freeze drying proved to be suitable operations to stabilise almond bagasse. Both drying methods, combined with appropriate grinding, provided powders with favourable properties for use in the food industry. Regarding the antiradical activity, there were no significant differences between the dehydrated samples, although the total phenol content was higher in the freeze-dried samples. After a 6-month storage period, an increase in antiradical capacity and total phenolic content was observed, particularly noticeable in the samples dried by hot air and subjected to accelerated storage. Acidity and peroxide index values increased considerably during accelerated storage, possibly due to the decomposition of fatty acids. Finally, the suitability of almond bagasse powder as a substitute ingredient in the production of bakery products was evaluated. The results indicated its suitability as a substitute for wheat flour in the production of biscuits, providing a product with appropriate texture, increased fibre content, and components with antiradical capacity. / Duarte Serna, S. (2024). Caracterización fisicoquímica, tecnológica y funcional del residuo procedente de la obtención de la bebida vegetal de almendra. Estrategias de valorización [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/204146 / Compendio