Ab initio design of efficient zeolite catalysts for methanol and hydrocarbons conversion

[ES] Toda esta disertación ha utilizado la química computacional como herramienta fundamental para el análisis científico. Por ello, en el Capítulo 2 se explican los modelos y métodos teóricos sobre este tema. La primera parte del capítulo se centra en los fundamentos de la química cuántica y, en concreto, se explica con detalle la Teoría del Funcional de la Densidad la cual constituye la base de los métodos computacionales aplicados. En esta sección, las nociones básicas del método Hartree-Fock sirven de prólogo a la DFT. El Capítulo 3 presenta los primeros resultados de este trabajo correspondientes a la reacción de metanol a olefinas catalizada por diferentes zeolitas con cavidades de poro pequeño. Esta reacción es un proceso industrial relevante que produce olefinas de cadena corta como eteno (C2=), propeno (C3=) y buteno (C4=) a escala industrial a partir de la biomasa. El sistema catalítico comprende tanto la estructura inorgánica de la zeolita que contiene los sitios ácidos Brønsted como las especies orgánicas confinadas, que forman la "hydrocarbon pool" y producen olefinas ligeras mediante pasos sucesivos de metilación y craqueo. Hemos centrado nuestros esfuerzos en comprender la naturaleza de la "hydrocarbon pool", una molécula de benceno polimetilada, y sus mecanismos de reacción para poder discernir entre ellos e identificar los catalizadores adecuados para mejorar la producción de propeno o eteno en función de la topología de cada cavidad zeolitica. Hemos podido identificar el grado de metilación de la "hydrocarbon pool" como el factor clave para potenciar el mecanismo de la ruta "paring", donde el propeno es el producto mayoritario, o el mecanismo de la ruta "side-chain", siendo el eteno el producto predominante. Este hallazgo nos permite establecer una relación entre la estabilización de los dos intermedios clave y la selectividad experimental observada con un alto grado de correlación. En el Capitulo 4 presentamos una nueva herramienta para el estudio de reacciones competitivas catalizadas por zeolitas. Utilizando un cribado computacional rápido con "force fields" para los intermedios clave de la reacción y un detallado estudio mecanístico usando la teoría del funcional de la densidad somos capaces de reconocer y cuantificar sutiles diferencias en la estabilización de intermedios y estados de transición dentro de huecos microporosos similares, aproximándonos así al nivel de reconocimiento molecular de las enzimas. Con estas herramientas somos capaces de seleccionar como catalizador una zeolita que obstaculice el mecanismo "alkyl-transfer" reduciendo la producción de eteno no deseado y potenciando al mismo tiempo el mecanismo "diaryl-mediated pathway". También somos capaces de obstaculizar la desproporción de dietilbenceno, una ruta no deseada del mecanismo "diaryl-mediated pathway" que conduce a la producción de trietilbenceno, mientras que se favorece la transalquilación de dietilbenceno aumentando el rendimiento obtenido de etilbenceno. en la primera sección del Capítulo 5, estudiamos la afinidad energética de cationes alquilamonio comercialmente disponibles con ligeras diferencias en sus grupos alquilo, TEA, MTEA y DMDEA, para la síntesis de CHA y sus efectos sobre la calidad del material obtenido. Evaluamos las energías de interacción entre la zeolita y el catión de diferentes combinaciones de agentes directores y cationes Na+ con métodos DFT periódicos pudiendo distinguir pequeños efectos de estabilización causados por ligeras diferencias estructurales entre moléculas que repercuten en la estructura final sintetizada. Durante la segunda sección del Capítulo 5, identificamos las características estructurales de diferentes agentes directores de estructura para la síntesis de AEI que mejoran las probabilidades de dispersión del Al en posiciones tetraédricas distintas de T1 obteniendo un catalizador AEI diferente de los sintetizados clásicamente.[CA] Tota aquesta dissertació utilitza la química computacional com eina fonamental per a l'anàlisi científica. Per això, en el Capítol 2 s'expliquen els models i mètodes teòrics sobre aquest tema. La primera part del capítol es centra en els fonaments de la química quàntica i, en concret, s'explica amb detall la Teoria del Funcional de la Densitat la qual constitueix la base dels mètodes computacionals aplicats. En aquesta secció, les nocions bàsiques del mètode Hartree-Fock serveixen de pròleg a la DFT. El Capítol 3 presenta els primers resultats d'aquest treball corresponents a la reacció de metanol a olefines catalitzada per diferents zeolites amb cavitats de porus petit. Aquesta reacció és un procés industrial rellevant que produeix olefines de cadena curta com etè (C2=), propè (C3=) i butè (C4=) a escala industrial a partir de la biomassa. El sistema catalític comprèn tant l'estructura inorgànica de la zeolita que conté els llocs àcids Brønsted com les espècies orgàniques confinades, que formen la "hydrocarbon pool" i produeixen olefines lleugeres mitjançant passos successius de metilació i craqueig. Hem centrat els nostres esforços en comprendre la naturalesa de la "hydrocarbon pool", una molècula de benzè polimetilada, i els seus mecanismes de reacció per a poder discernir entre ells i identificar els catalitzadors adequats per millorar la producció de propè o etè en funció de la topologia de cada cavitat zeolitica. Hem pogut identificar el grau de metilació de la "hydrocarbon pool" com el factor clau per a potenciar el mecanisme de la ruta "paring", on el propè és el producte majoritari, o el mecanisme de la ruta "side-chain", sent l'etè el producte predominant. Al Capítol 4 presentem una nova eina per a l'estudi de reaccions competitives catalitzades per zeolites. Utilitzant un cribratge computacional ràpid amb "force fields" per als intermedis clau de la reacció i un detallat estudi mecanístic amb la teoria del funcional de la densitat som capaços de reconèixer i quantificar subtils diferències en l'estabilització d'intermedis i estats de transició dins de buits microporosos similars, aproximant-nos així al nivell de reconeixement molecular dels enzims. en la primera secció del Capítol 5, estudiem l'afinitat energètica de cations alquilamoni comercialment disponibles amb lleugeres diferències als seus grups alquil, TEA, MTEA i DMDEA, per a la síntesi de CHA i els seus efectes sobre la qualitat del material obtingut. Avaluem les energies d'interacció entre la zeolita i el catió entre diferents combinacions d'agents directors i cations Na+ amb mètodes DFT periòdics podent distingir petits efectes d'estabilització causats per lleugeres diferències estructurals entre molècules que repercuteixen en l'estructura final sintetitzada. Durant la segona secció del Capítol 5, identifiquem les característiques estructurals de diferents agents directors d'estructura per a la síntesi d'AEI que milloren les probabilitats de propagació de l'Al a través de posicions tetrahedriques diferents de T1 obtenint un catalitzador AEI diferent dels sintetitzats clàssicament.[EN] Computational chemistry has been used as the fundamental tool during the whole work. Therefore, the theoretical models and methods on this subject are explained in Chapter 2. The first part sketches the fundamentals of quantum chemistry and specifically explains the Density Functional Theory that constitutes the basis of the computational methods applied. In this section, basic notions of the Hartree-Fock method serve as prologue for DFT after which more practical aspects are elucidated. Chapter 3 presents the first results of this work corresponding to the methanol to olefins reaction catalysed by different small-pore cage-like zeolites. This reaction is a relevant process that produces short chain olefins such as ethene, propene and butene at industrial scale from biomass. The catalytic system comprises both the zeolite inorganic framework containing the Brønsted acid sites and the confined organic species, that form the hydrocarbon pool and produce light olefins by successive methylation and cracking steps. Our efforts are focused on understanding the nature of the hydrocarbon pool, a polymethylated benzene molecule, and its reaction mechanisms in order to be able to discern between them and identify the proper catalysts to enhance propene or ethene production based on each zeolite cavity topology. We have been able to identify the hydrocarbon pool methylation degree as the key factor to enhance paring route mechanism where propene is the predominant product, or side-chain mechanism, with ethene being the predominant product. This finding enables us to establish a relation between the stabilization of the two key intermediates and the experimental selectivity observed with a high degree of correlation. In Chapter 4 we present a new tool for the study of competing reactions catalyzed by zeolites. Using a fast computational screening with force fields for the key intermediates of the reaction and a detailed density functional theory mechanistic study we are able to recognize and quantify subtle differences in the stabilization of intermediates and transition states within similar microporous voids, thus approaching the level of molecular recognition of enzymes. With these tools we are able to select a zeolite catalyst that hinders alkyl-transfer mechanism reducing the production of non-desired ethene while enhancing the diaryl-mediated pathyways mechanism. Once we discard the non-desired mechanism, we are also able to hinder the diethylbenzene disproportionation, a non-desired route of the diaryl-mediated pathways that leads to triethylbenzene production, while favouring diethylbenzene transalkylation increasing the obtained yield of ethylbenzene. To close this chapter, the theoretical results are compared with experimental selectivities obtained for eight candidate zeolites obtaining a good correlation between theory and experiment. in the first section of Chapter 5, we study the energetic affinity of commercially available alkylammonium cations with slight differences on their alkyl chain groups, as TEA, MTEA and DMDEA, for CHA synthesis and its effects on the quality of the material obtained. We evaluate the host-guest interaction energies of different combinations of OSDAs and Na+ cations with periodic DFT methods being able to distinguish small stabilization effects caused by slight structural differences between molecules that have an impact on the final structure synthesized. On the other hand, we present a new theoretical methodology to address Al positioning prediction in SSZ-39 zeolite with the AEI framework. During the second section of Chapter 5, we identify the structural features of different OSDAs for AEI synthesis that improve the probabilities of spreading Al through different T-site positions other than T1 obtaining an AEI catalyst different from the classically synthesized.Vull agrair al Instituto de Tecnología Química per la concessió d’un contracte predoctoral, a la Red Española de Supercomputación (RES), al Centre de Càlcul de la Universitat de València, al Flemish Supercomputer Center (VSC) de la Ghent University pels recursos computacionals i el suport tècnic, a la Unió Europea i al Gobierno de España pel finançament d’aquest projecte a traves dels programes ERC-AdG-2014- 671093 (SynCatMatch) “Severo Ochoa” (SEV-2016-0683, MINECO) i dels projectes MAT2017-82288-C2-1-P i PID2020-112590GB-C21 (AEI/FEDER, UE), i al CSIC pel finançament de la estada al CMM a través del projecte i- Link (LINKA20381).Ferri Vicedo, P. (2023). Ab initio design of efficient zeolite catalysts for methanol and hydrocarbons conversion [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/19349

Manual de introducción a las comunidades virtuales

Una comunitat virtual és un lloc d'Internet on un conjunt de persones comparteixen els mateixos interessos i necessitats. En aquesta es dóna una interacció i comunicació entre els membres. Aquest manual ens ofereix una guia de recursos sobre les eines comunes en aquestes comunitats, així com una descripció exhaustiva sobre elles. Trobarem també alguns exemples de comunitats virtuals existents avui en dia.Una comunidad virtual es un sitio de Internet donde un conjunto de personas comparten los mismos intereses y necesidades. En ésta se da una interacción y comunicación entre los miembros. Este manual nos ofrece una guía de recursos sobre las herramientas comunes en estas comunidades, así como una descripción exhaustiva sobre ellas. Encontraremos también algunos ejemplos de comunidades virtuales existentes hoy en día.A virtual community is a website where a group of people share the same interests and needs. There are interaction and communication processes among members. This user's guide offers a collection of resources on common tools in these communities, as well as a comprehensive description about them. Find some examples of existing virtual communities

Utilización de Technosols en la resolución de problemas ambientales: depuración de aguas y restauración de suelos

Son numerosas las actividades humanas que producen impactos negativos sobre el medio ambiente, ya que generan, entre otros, efluentes como las aguas residuales que necesitan ser depuradas antes de su vertido a cauce público o su reutilización, y contaminación del medio natural como consecuencia de actividades antrópicas, como la minería. Nuestro trabajo se centra, fundamentalmente, en contribuir al conocimiento del uso de Technosols en los procesos de depuración de aguas, y en la restauración de zonas contaminadas por efecto de actividades mineras, como una alternativa a la solución de los problemas ambientales.There are numerous human activities that produce negative impacts on the environment, since they generate, among others, effluents such as wastewater that need to be purified before being discharged into public watercourses or reused, and pollution of the natural environment as a result of activities anthropic, such as mining. Our work is fundamentally focused on contributing to the knowledge of the use of technosols in water purification processes, and in the restoration of areas contaminated by the effect of mining activities, as an alternative to solving environmental problems

Design and Synthesis of the Active Site Environment in Zeolite Catalysts for Selectively Manipulating Mechanistic Pathways

[EN] By combining kinetics and theoretical calculations, we show here the benefits of going beyond the concept of static localized and defined active sites on solid catalysts, into a system that globally and dynamically considers the active site located in an environment that involves a scaffold structure particularly suited for a target reaction. We demonstrate that such a system is able to direct the reaction through a preferred mechanism when two of them are competing. This is illustrated here for an industrially relevant reaction, the diethylbenzene-benzene transalkylation. The zeolite catalyst (ITQ-27) optimizes location, density, and environment of acid sites to drive the reaction through the preselected and preferred diaryl-mediated mechanism, instead of the alkyl transfer pathway. This is achieved by minimizing the activation energy of the selected pathway through weak interactions, much in the way that it occurs in enzymatic catalysts. We show that ITQ-27 outperforms previously reported zeolites for the DEB-Bz transalkylation and, more specifically, industrially relevant zeolites such as faujasite, beta, and mordenite.This work was supported by the European Union through ERC-AdG-2014-671093 (SynCatMatch), Spanish Government through "Severo Ochoa" (SEV-2016-0683, MINECO), MAT2017-82288-C2-1-P (AEI/FEDER, UE) and RTI2018-10103-B-I00 (MCIU/AEI/FEDER, UE), and by Generalitat Valenciana through AICO/2019/060. The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. Red Espanola de Supercomputacion (RES) and Servei d'Informatica de la Universitat de Valencia (SIUV) are acknowledged for computational resources and technical support. P. F. and C. Li thank ITQ for their contract.Li, C.; Ferri-Vicedo, P.; Paris, C.; Moliner Marin, M.; Boronat Zaragoza, M.; Corma Canós, A. (2021). Design and Synthesis of the Active Site Environment in Zeolite Catalysts for Selectively Manipulating Mechanistic Pathways. Journal of the American Chemical Society. 143(28):10718-10726. https://doi.org/10.1021/jacs.1c0481810718107261432

The Limits of the Confinement Effect Associated to Cage Topology on the Control of the MTO Selectivity

This is the peer reviewed version of the following article: P. Ferri, C. Li, C. Paris, A. Rodríguez-Fernández, M. Moliner, M. Boronat, A. Corma, ChemCatChem 2021, 13, 1578, which has been published in final form at https://doi.org/10.1002/cctc.202001760. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] The light olefin product distribution of the methanol-to-olefin (MTO) reaction catalyzed by acid zeolites and zeotypes depends on the nature of the entrapped hydrocarbon pool species that act as co-catalysts. The preferential stabilization by confinement effects of the cationic intermediates involved in the side-chain or paring pathways of the aromatics-based cycle of the MTO mechanism in small-pore cage-based zeolites is determined by the topology of the cavity, and can be quantitatively described through the E-int(7/5) parameter obtained from DFT calculations. In this work we extend the study of the E-int(7/5) parameter to a wide range of structures (ERI, LEV, AEI, CHA, DDR, AFX, RTH, ITE, SAV, UFI, RHO, KFI, and LTA) and discuss its applicability in small cages with steric constraints to host bulky intermediates, in zeolites with a tight fitting between the cavity and the hosted cations, and in large cages where confinement effects are lost in part and competitive processes occur.This work has been supported by the European Union through ERC-AdG-2014-671093 (SynCatMatch), Spanish Government through ''Severo Ochoa" (SEV-2016-0683, MINECO), MAT2017-82288-C2-1-P (AEI/FEDER, UE) and RTI2018-101033-B-I00 (MCIU/AEI/FEDER, UE), and by Generalitat Valenciana through AICO/2019/060. The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. Red Espanola de Supercomputacion (RES) and Servei d'Informatica de la Universitat de Valencia (SIUV) are acknowledged for computational resources and technical support. P.F. and C.L. thank ITQ for their contracts. A.R.F. acknowledges the Spanish Government-MINECO for a FPU scholarship (FPU2017/01521).Ferri-Vicedo, P.; Li, C.; Paris, C.; Rodríguez-Fernández, A.; Moliner Marin, M.; Boronat Zaragoza, M.; Corma Canós, A. (2021). The Limits of the Confinement Effect Associated to Cage Topology on the Control of the MTO Selectivity. ChemCatChem. 13(6):1578-1586. https://doi.org/10.1002/cctc.202001760S1578158613

Chemical and Structural Parameter Connecting Cavity Architecture, Confined Hydrocarbon Pool Species, and MTO Product Selectivity in Small-Pore Cage-Based Zeolites

"This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Catalysis, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acscatal.9b04588"[EN] The catalysts used in the methanol-to-olefins (MTO) reaction are considered dual systems comprising an inorganic zeolite framework and organic compounds hosted inside that act as cocatalysts. The influence of zeolite cavity architecture on the preferential stabilization of cationic intermediates involved in the paring and side-chain routes of the hydrocarbon pool mechanism is analyzed by means of density functional theory (DFT) calculations, catalyst testing, and C-13 NMR spectroscopy for some small-pore cage-based zeolites. A correlation between the degree of methylation of the entrapped methylbenzenium (MB+) cations and the selectivity to ethene and propene is found experimentally and explained in terms of the electronic distribution of the first intermediate of the paring route. A deep understanding of the reaction mechanism and of the specific host guest interactions taking place inside zeolite catalysts allows establishing a quantitative parameter that is indicative for the contribution of the paring route and therefore the C-3(=)/C-2(=) ratio in the MTO reaction.This work has been supported by the European Union through ERC-AdG-2014-671093 (SynCatMatch), Spanish Government through "Severo Ochoa" (SEV-2016-0683, MINECO), MAT2017-82288-C2-1-P (AEI/FEDER, UE), and RTI2018-101033-B-100 (MCIU/AEI/FEDER, UE), and by the Fundacion Ramon Areces through a research contract (CIVP18A3908). The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. Red Espanola de Supercomputacion (RES) and Servei d'Informatica de la Universitat de Valencia are acknowledged for computational resources and technical support. C.L. acknowledges the China Scholarship Council (CSC) for a Ph.D. fellowship. P.F. thanks ITQ for acontract. The authors thank Prof. Fernando Rey and Dr. Joaquin Martinez for helpful discussions.Ferri-Vicedo, P.; Li, C.; Paris, C.; Vidal Moya, JA.; Moliner Marin, M.; Boronat Zaragoza, M.; Corma Canós, A. (2019). Chemical and Structural Parameter Connecting Cavity Architecture, Confined Hydrocarbon Pool Species, and MTO Product Selectivity in Small-Pore Cage-Based Zeolites. ACS Catalysis. 9(12):11542-11551. https://doi.org/10.1021/acscatal.9b04588S115421155191

Impact of Zeolite Framework Composition and Flexibility on Methanol-To-Olefins Selectivity: Confinement or Diffusion?

This is the peer reviewed version of the following article: P. Ferri, C. Li, R. Millán, J. Martínez-Triguero, M. Moliner, M. Boronat, A. Corma, Angew. Chem. Int. Ed. 2020, 59, 19708, which has been published in final form at https://doi.org/10.1002/anie.202007609. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] The methanol-to-olefins reaction catalyzed by small-pore cage-based acid zeolites and zeotypes produces a mixture of short chain olefins, whose selectivity to ethene, propene and butene varies with the cavity architecture and with the framework composition. The product distribution of aluminosilicates and silicoaluminophosphates with the CHA and AEI structures (H-SSZ-13, H-SAPO-34, H-SSZ-39 and H-SAPO-18) has been experimentally determined, and the impact of acidity and framework flexibility on the stability of the key cationic intermediates involved in the mechanism and on the diffusion of the olefin products through the8rwindows of the catalysts has been evaluated by means of periodic DFT calculations and ab initio molecular dynamics simulations. The preferential stabilization by confinement of fully methylated hydrocarbon pool intermediates favoring the paring pathway is the main factor controlling the final olefin product distribution.This work has been supported by the European Union through ERC-AdG-2014-671093 (SynCatMatch), Spanish Government through "Severo Ochoa" (SEV-2016-0683, MINECO), MAT2017-82288-C2-1-P (AEI/FEDER, UE) and RTI2018-101033-B-I00 (MCIU/AEI/FEDER, UE), and by Generalitat Valenciana through AICO/2019/060. The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. Red Espanola de Supercomputacion (RES) and Servei d'Informatica de la Universitat de Valencia (SIUV) are acknowledged for computational resources and technical support. P.F. and R.M. thank ITQ for their contracts. C.L. acknowledges China Scholarship Council (CSC) for a Ph.D fellowship.Ferri-Vicedo, P.; Li, C.; Millán-Cabrera, R.; Martínez-Triguero, J.; Moliner Marin, M.; Boronat Zaragoza, M.; Corma Canós, A. (2020). Impact of Zeolite Framework Composition and Flexibility on Methanol-To-Olefins Selectivity: Confinement or Diffusion?. Angewandte Chemie International Edition. 59(44):19708-19715. https://doi.org/10.1002/anie.202007609S19708197155944Olah, G. A. (2005). Beyond Oil and Gas: The Methanol Economy. Angewandte Chemie International Edition, 44(18), 2636-2639. doi:10.1002/anie.200462121Olah, G. A. (2005). Jenseits von Öl und Gas: die Methanolwirtschaft. Angewandte Chemie, 117(18), 2692-2696. doi:10.1002/ange.200462121Tian, P., Wei, Y., Ye, M., & Liu, Z. (2015). Methanol to Olefins (MTO): From Fundamentals to Commercialization. ACS Catalysis, 5(3), 1922-1938. doi:10.1021/acscatal.5b00007Haw, J. F., Song, W., Marcus, D. M., & Nicholas, J. B. (2003). The Mechanism of Methanol to Hydrocarbon Catalysis. Accounts of Chemical Research, 36(5), 317-326. doi:10.1021/ar020006oOlsbye, U., Svelle, S., Bjørgen, M., Beato, P., Janssens, T. V. W., Joensen, F., … Lillerud, K. P. (2012). Conversion of Methanol to Hydrocarbons: How Zeolite Cavity and Pore Size Controls Product Selectivity. Angewandte Chemie International Edition, 51(24), 5810-5831. doi:10.1002/anie.201103657Olsbye, U., Svelle, S., Bjørgen, M., Beato, P., Janssens, T. V. W., Joensen, F., … Lillerud, K. P. (2012). Umwandlung von Methanol in Kohlenwasserstoffe: Wie Zeolith-Hohlräume und Porengröße die Produktselektivität bestimmen. Angewandte Chemie, 124(24), 5910-5933. doi:10.1002/ange.201103657Van Speybroeck, V., De Wispelaere, K., Van der Mynsbrugge, J., Vandichel, M., Hemelsoet, K., & Waroquier, M. (2014). First principle chemical kinetics in zeolites: the methanol-to-olefin process as a case study. Chem. Soc. Rev., 43(21), 7326-7357. doi:10.1039/c4cs00146jYarulina, I., Chowdhury, A. D., Meirer, F., Weckhuysen, B. M., & Gascon, J. (2018). Recent trends and fundamental insights in the methanol-to-hydrocarbons process. Nature Catalysis, 1(6), 398-411. doi:10.1038/s41929-018-0078-5Moliner, M., Martínez, C., & Corma, A. (2013). Synthesis Strategies for Preparing Useful Small Pore Zeolites and Zeotypes for Gas Separations and Catalysis. Chemistry of Materials, 26(1), 246-258. doi:10.1021/cm4015095McCann, D. M., Lesthaeghe, D., Kletnieks, P. W., Guenther, D. R., Hayman, M. J., Van Speybroeck, V., … Haw, J. F. (2008). 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NH3-SCR catalysts for heavy-duty diesel vehicles: Preparation of CHA-type zeolites with low-cost templates

Computer-assistance allows selecting the most adequate low-cost organic structure directing agents (OSDAs) for the crystallization of Al-rich CHA-type zeolites. The host-guest stabilization energies of tetraethylammonium (TEA), methyltriethylammonium (MTEA) and dimethyldiethylammonium (DMDEA), in combination with Na, were first theoretically evaluated. This “ab-initio” analysis reveals that two TEA show a serious steric hindrance in a cha cavity, whereas two MTEA would present excellent host-guest confinements. The synthesis of Al-rich CHA-type zeolites has been accomplished using TEA and MTEA. Electron diffraction and high-resolution transmission electron microscopy reveal large CHA-domains with narrow faulted GME-domains in the CHA-type material synthesized with TEA, confirming the better OSDA-directing roles of MTEA cations towards the cha cavity, in good agreement with DFT calculations. Cu-exchanged Al-rich CHA-type samples achieved with MTEA and TEA show excellent catalytic activity and hydrothermal stability for the selective catalytic reduction (SCR) of NOx with ammonia under conditions relevant for future heavy duty diesel conditions.This work has been supported by Umicore and by the Spanish Government-MCIU through RTI2018-101033-B-I00 (MCIU/AEI/FEDER, UE) and PID2020-112590GB-C21 (AEI/FEDER, UE). T.W. acknowledges financial support by the Swedish Research Council (Grant No. 2019-05465). E.B. acknowledges the Spanish Government-MCIU for a FPI scholarship (PRE2019-088360). P.F. thanks ITQ for a contract. The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. The computations were performed on the Tirant III cluster of the Servei d'Informàtica of the University of Valencia

WeObserve:An Ecosystem of Citizen Observatories for Environmental Monitoring

The last decade has witnessed a rise in the field of citizen science which can be described as a collaborative undertaking between citizens and scientists to help gather data and create new scientific knowledge. In the EU, efforts have been channeled into developing the concept of Citizen Observatories (COs), which have been supported via the Seventh Framework Program (FP7) and continue to be funded in Horizon 2020. COs, often supported by innovative technologies including Earth Observation (EO) and mobile devices, are the means by which communities can monitor and report on their environment and access information that is easily understandable for decision making. To improve the coordination between existing COs and related citizen science activities, the WeObserve project tackles three key challenges that face COs: awareness, acceptability and sustainability. The WeObserve mission is to create a sustainable ecosystem of COs that can systematically address these identified challenges and help move citizen science into the mainstream. The WeObserve approach will apply several key instruments to target, connect and coordinate relevant stakeholders. The first is to develop and foster five communities of practice to strengthen the current knowledge base surrounding COs. Topics will include citizen engagement, the value of COs for governance and CO data interoperability. In co-creating this knowledge base, CO practitioners will have a platform to effectively share best practices and avoid duplication. Secondly, the project will expand the geographical reach of the knowledge base to different target groups via toolkits, a Massive Open Online Course (MOOC), capacity development roadshows and an Open Data Exploitation Challenge, to strengthen the uptake of CO-powered science by public authorities and SMEs. A third mechanism will forge links with GEOSS and Copernicus to demonstrate how COs can complement the EU’s Earth Observation monitoring framework. This paper will describe these various mechanisms and issue a call to bring together diverse stakeholders who share a joint (practice-oriented) interest in citizen science. The WeObserve consortium brings together the current H2020 COs (Ground Truth 2.0, GROW, LandSense, Scent) who will actively open up the citizen science landscape through wide ranging networks, users and stakeholders, including ECSA, GEOSS and Copernicus to foster social innovation opportunities. The WeObserve approach and outcomes have the potential to create a step-change in the Earth Observation sector and make COs a valuable component of Earth system science research to manage environmental challenges and empower resilient communities