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Descripción de 1 páginas de la comunicación oral presentada en Oxizymes2022 10th edition of the international “Oxizymes” meeting. Siena, Italy, July 5-8, 2022, Basidiomycetes of the class Agaricomycetes have developed complex enzymatic machineries that allow them to decompose plant polymers, including lignin. Within this group, saprotrophic Agaricales are characterized by an unparalleled diversity of habitats and lifestyles in comparison with fungi from other orders. With the aim of shedding light on the evolution of lignocellulose-decaying lifestyles in Agaricales we conducted a comparative analysis of 52 Agaricomycetes genomes [1]. This study revealed that Agaricales possess a large diversity of hydrolytic and oxidative enzymes. Surprisingly, computer-assisted gene-family evolution analysis of these enzymes revealed that a few oxidoreductase families showed significantly higher evolutionary rates. Based on these gene families we reconstructed the lifestyles of the ancestors that led to the extant lignocellulose-decomposing Agaricomycetes. According to this, we determined that changes in the oxidative enzymatic toolkit of ancestral Agaricales correlate with the evolution of their ability to grow not only on wood, but also on leaf and grass litter and decayed wood. In this context, the aboye families were analyzed and special attention was paid to peroxidases as a central component of the enzymatic toolkit of saprotrophic Agaricomycetes responsible for lignin degradation. We identified a widespread presence of new ligninolytic peroxidase types in Agaricales, some of them not previously identified in this order, and others also not found in woodrottingPolyporales and other orders of Agaricomycetes. Peroxidase evolution was analyzed in Agaricomycetes by ancestral sequence reconstruction and several major evolutionary pathways were unveiled. The study of the newly identified peroxidases will provide insight into their role in the lignin degradation process. In fact, these studies have already been initiated with the expression and characterization of the first lignin peroxidase identified in Agaricales. [1] Ruiz-Dueñas FJ, Barrasa JM, Sánchez-García M, Camarero S, Miyauchi S, Serrano A, et al., 2021, Mol Biol Evol, 38, 1428-1446., Projects/contracts BI02017-86559-R, BI02015-7369-JIN, AGL2014-55971-R, NSFgrant-1457721 , CEFOX-031 B0831 S, PIE-201620E081 , ANR-11-LABX-0002-01 , US-DOE-DE-AC02-05CH11231

The present invention concerns a material with a non-stoichiometric spinel-type crystalline structure based on cobalt oxide doped with alkaline elements, its production process for obtaining it by precipitation with controlled washing, and its particular use as a highly active catalyst in the N2O decomposition reaction. Therefore, we understand that the present invention is in the area of green industry aimed at reducing N2O emissions into the atmosphere., Consejo Superior de Investigaciones Científicas (CSIC), A1 Solicitud de patente con informe sobre el estado de la técnica

本发明涉及基于掺杂有碱性元素的氧化钴的具有非化学计量尖晶石型晶体结构的材料，其生产方法是通过控制洗涤来沉淀从而获得所述材料，以及所述材料在N2O分解反应中作为高活性催化剂的特定用途。因此，我们理解本发明属于旨在减少N2O排放的绿色工业领域。, Consejo Superior de Investigaciones Científicas (CSIC)

[EN] The present invention relates to: a crystal-structured spinel-type non-stoichiometric material based on cobalt oxide doped with alkaline elements; a method for obtaining same by means of precipitation with controlled washing; and the particular use thereof as a highly active catalyst in an N2O decomposition reaction. The invention falls within the area of the green industry for reducing N2O emissions into the atmosphere. [FR] La présente invention concerne un matériau àstructure cristalline de type spinelle non stoechiométrique à base d'oxyde de cobalt dopé avec des éléments alcalins, son procédé d'obtention par précipitation avec lavage contrôlé, et son utilisation particulière comme catalyseur à forte activité dans la réaction de décomposition de N2O. Par conséquent, la présente invention s'inscrit dans le domaine de l'industrie verte visant à la réduction des émissions de N2O dans l'atmosphère., Consejo Superior de Investigaciones Científicas (CSIC), A1 Solicitud de patente con informe sobre el estado de la técnica

A presente invenção refere-se a um material com estrutura cristalina do tipo espinélio não estequiométrica à base de óxido de cobalto dopado com elementos alcalinos, seu processo de produção para obtenção por precipitação com lavagem controlada e seu uso particular como catalisador altamente ativo na reação de decomposição de N2O. Portanto, entende-se que a presente invenção está na área da indústria verde visando a redução das emissões de N2O na atmosfera., Consejo Superior de Investigaciones Científicas (CSIC), A2 Solicitud de patente sin informe sobre el estado de la técnica

La presente invención se refiere a un material de estructura cristalina de tipo espinela no estequiométrica basada en óxido de cobalto dopado con elementos alcalinos, a su procedimiento de obtención mediante precipitación con lavado controlado, y a su uso particular como catalizador de gran actividad en la reacción de descomposición de N2O. Por tanto, entendemos que la presente invención se sitúa en el área de la industria verde dirigida a la reducción de las emisiones de N2O a la atmósfera. [ES], The present invention relates to: a crystal-structured spinel-type non-stoichiometric material based on cobalt oxide doped with alkaline elements; a method for obtaining same by means of precipitation with controlled washing; and the particular use thereof as a highly active catalyst in an N2O decomposition reaction. The invention falls within the area of the green industry for reducing N2O emissions into the atmosphere. [EN], Consejo Superior de Investigaciones Científicas (CSIC), A1 Solicitud de patente con informe sobre el estado de la técnica

Trabajo presentado en el Congreso Iberoamericano de Hidrógeno y Pilas de Combustible, celebrado en Barcelona (España) del 15 al 17 de octubre de 2014., [EN] The aim of this work was to study the influence of H20/CH4 ratio over the activity and stability of a La-promoted hydrotalcite-derived catalyst in biogas reforming, as a pathway to transform biogas into hydrogen. Biogas composition was CH4/C02 de 2.33. Catalytic tests were performed at 700 ºC and a W/F ratio of 0.25 mg ·min·cm-3. Four tests were performed in which H20/CH4 ratio were changed from O to 1.6. Water addition led to an increase of activity (measured as the increase of methane conversion). None of the catalysts showed any sign of deactivation. H2/CO ratio increased significantly when water was added. lt may be due to the fact that H20 also contribute to H2 formation . Used catalysts where characterized by TPO-MS and TEM microscopy. When H20/CH4 ¿0,8 no carbon deposits were detected, what suggested that ali the formed carbon was gasified. Ni particle size was 3-4 nm in ali cases which could explain the good stability of the catalysts under these sever conditions., [ES] En este trabajo se ha estudiado la influencia de la relación H20/CH4 sobre la actividad y estabilidad de un catalizador promovido por lantano y derivado del precursor hidrotalcita (La-NiMgAlO ) en la reacción de reformado de biogás, como vía para obtener hidrógeno de una fuente renovable. El biogás testado tiene una composición CH4/C02 de 2,33. Los ensayos se realizaron a 700 ºC y una relación W/F = 0,25 mg ·min·cm-3 y se mantuvieron durante 5h. Se realizaron 4 ensayos en los que se varió la relación H20/CH4 desde O a 1,6. La adición de agua provocó un aumento de la actividad (medida como el aumento en la conversión de metano) y una menor formación de carbono. En ninguno de los experimentos se detectó desactivación . La relación H2/CO aumentó de forma notable al adicionar H20 debido a que en ese caso la fuente de H2 no sería únicamente el CH4 si no también el H20 . Los catalizadores usados se caracterizaron mediante TPO-MS y microscopía TEM. Cuando la relación H20/CH4 ¿0,8 no se detectaron depósitos carbonosos, lo que indica que todo el carbono formado por la descomposición del metano es gasificado . El tamaño de partícula de Ni fue en todos los casos de 3-4 nm lo que podría explicar la buena estabilidad observada., Este trabajo ha sido financiado por la Comunidad de Madrid (Programa DIVERCEL-CM, S2009/ENE-1475).

Trabajo presentado en el Congreso Iberoamericano de Hidrógeno y Pilas de Combustible, celebrado en Barcelona (España) del 15 al 17 de octubre de 2014., [EN] The influence of lanthanum content has been studied in three catalysts obtained after calcination at 750 ºC of hydrotalcite precursors, which were previously synthesized by co-precipitation method. Firstly, the precursors were characterised by X-ray diffraction and TPO, confirming the hydrotalcite structure. The catalysts were also characterised by X- ray diffraction where Mg(Ni, Al)O phase was detected. No peak related to lanthanum oxide or other related specie was observed. BET areas were higher than precursors’ in all the cases, being higher in the catalyst with higher La content. Catalytic tests at 700 ºC, W/F = 0,4 mg·min·cm-3 and a feed ratio of CH4:CO2 1:1 were performed. Conversions under equilibrium were evaluated in order to avoid fake stability due to an excess of active sites. The lower the La content, the lower methane conversion became. However, carbon deposition rate was higher in the catalyst with the lowest La content, which may be explained by its higher acidity. Above all, it is remarkable the good stability detected in every catalyst, showing no sign of deactivation during 50 h., [ES] Tres catalizadores obtenidos tras la calcinación a 750 ºC de sus correspondientes hidrotalcitas (sintetizadas mediante co-precipitación a baja supersaturación) se estudiaron con el fin de determinar la influencia del contenido en La sobre la actividad y estabilidad en la reacción de reformado seco de metano. Inicialmente, los precursores se caracterizaron mediante DRX y TPO para confirmar la obtención de la estructura hidrotalcita. Tras la calcinación, los catalizadores se caracterizaron mediante DRX, observándose la formación de la fase Mg(Ni, Al)O. No se observó ningún pico asociado a óxido de lantano y alguna otra especie. Las áreas BET determinadas fueron superiores a las obtenidas para los precursores, siendo más elevada para la de mayor contenido en lantano. Los catalizadores se ensayaron en reacción a 700 ºC, una W/F de 0,4 mg·min·cm- 3 y una relación CH4:CO2 1:1. Se trabajó por debajo de la conversión de equilibrio para evitar una falsa estabilidad debida a un exceso de centros activos. La conversión de metano fue menor conforme el contenido en lantano disminuía; sin embargo, la tasa de deposición de carbono fue superior en el catalizador con menor contenido en promotor. Esto podría explicarse por la mayor acidez detectada en este catalizador. Sin embargo, es destacable que los tres catalizadores se mantuvieron estables durante 50 h de reacción, sin mostrar ningún signo de desactivación., Este trabajo ha sido financiado por la Comunidad de Madrid (Programa DIVERCEL-CM, S2009/ENE-1475) y el CSIC (Proyecto Intramural 201280E132).

Trabajo presentado en la European Hydrogen Energy Conference - EHEC, celebrada en Sevilla (España) del 12 al 14 de mayo de 2014., Biogas is a hydrogen source produced by the anaerobic digestion of organic matter present on waste. The utilization of this resource not only constitutes an alternative fuel that can reduce fossil fuel dependency and emissions of greenhouse gases, but also helps to reduce all the organic matter present on waste [1]. The hydrogen, obtained from biogas can be used to feed certain types of fuel cells, which offer the advantages of higher efficiencies and neither pollutants nor greenhouse gases generation. Since CH4 and CO2 are the main components present in biogas [2], CO2 reforming of methane constitutes an interesting process to study. The major drawback of this reaction is catalyst deactivation, mainly produced by carbon deposition [3,4]. Sepiolite is a good material as catalytic support due to their fibrous structure and open porous network [5] but it has not been studied in dry reforming of methane. On the surface of the sepiolite there are both alkaline center (Mg, O tetrahedron) and acid center (Si, O tetrahedron). Since acidity seems to favor carbon deposition, two lanthanides has been added in order to see its influence in the Ni-based catalyst for biogas reforming., Financial support from Comunidad de Madrid (DIVERCELCM, S2009/ENE-1475) is gratefully acknowledged.

Trabajo presentado en el Congreso Iberoamericano de Hidrógeno y Pilas de Combustible, celebrado en Barcelona (España) del 15 al 17 de octubre de 2014., [EN] Three sepiolite-su pported catalysts have been synthesi zed using impregnation method. Active phase was Ni while Ce was used as a promoter . These catalysts were prepared in order to study the influence of different sepiolites over activity and stability during dry reforming of methane. Firstly, the supports were characterized by XRD and TPO and catalysts were studied by XRD and TPR techniques. Different phases was detected in every catalyst (sepiolite, anhydre sepiolite , Si02' Ce02 y Ni). According to TPR, reduction temperature should be 550 ºC, what indicate the existence of an interaction between NiO and the support. Catalytic tests at 700 ºC, W/F = 0,4 mg ·min·cm-3 and a feed ratio of CH :C0 1:1 were performed . Catalytic activity was higher when using PAN catalysts while stability was higher when SEP catalyst was used. Carbon deposition rate was higher in SEP which agrees with its higher stability, while PAN showed the highest carbon deposition rate., [ES] Se han sintetizado 3 catalizadores soportados sobre 3 sepiolita. La fase activa fue Ni y se usó como promotor Ce, siendo el método de síntesis la impregnación en disolución . Se estudiaron con el fin de evaluar la influencia del soporte sobre la actividad y estabilidad en la reacción de reformado seco de metano. Inicialmente , los soportes se caracterizaron mediante DRX y TPO. Los catalizadores se caracterizaron mediante DRX, detectándose las fases sepiolita , sepiolita anhidra, Si02, Ce02 y NiO y por TPR, observándose perfiles similares donde NiO se reduce a 550 ºC, es decir existe cierta interacción entre NiO y el soporte. Por ello, en los test catalíticos ésta fue la temperatura empleada. Las condiciones de los ensayos fueron 700 ºC, W/F = 0,4 mg ·min·cm-3 y una relación CH :C0 1:1 y se mantuvieron durante lOh. La actividad catalítica fue superior en el catalizador PAN seguido por NFAC y por último SEP, pero fue éste el que se mostró más estable después de una ligera desactivación durante las primeras 2 horas. PAN fue el que mayor tasa de deposición de carbono, mientras que SEPfue el que menos carbono depositó , lo que explicaría su mayor estabilidad., Este trabajo ha sido financiado por la Comunidad de Madrid (Programa DIVERCEL-CM, S2009/ENE-1475) y el CSIC (Proyecto Intramural 201280El32).

Trabajo presentado en la European Hydrogen Energy Conference - EHEC, celebrada en Sevilla (España) del 12 al 14 de mayo de 2014., There is a growing interest in the development of power sources that use renewable fuels and reduce emission of pollutants. This interest is justified by the heightening concern about environmental degradation, energy security as well as the possible exhaustion of the fossil fuel resources. One example is the use of biogas (mainly composed by CH4 and CO2) which is generated from anaerobic digestion of sewage or wastewater [1]. In order to produce hydrogen from this renewable gas, it is necessary a reforming step. There are two alternatives: 1) carbon dioxide reforming (DR: CH4 + CO2 2H2 + 2CO) and 2) steam reforming (SR: CH4 + H2O  3H2 + CO). The first reaction has two drawbacks: the deactivation of the catalyst due to carbon deposition [2] and the participation of reverse water-gas-shift (RWGS: H2 + CO2  H2O + CO) which decreases the amount of the produced hydrogen. On the other hand, steam reforming is the most extended way to produce hydrogen from CH4, but it is necessary to eliminate the CO2 from the feed. Since previous studies [3] had reported good results when La-promoted catalysts, obtained from hydrotalcite-like precursor calcination, were used in dry reforming of methane, this catalyst will be used for these tests. The aim of this work is to study the influence of H2O addition over dry reforming and the addition of CO2 over steam reforming using a La-promoted catalyst obtained from hydrotalcite-like precursor., Financial support from Comunidad de Madrid (DIVERCELCM, S2009/ENE-1475) is gratefully acknowledged.

Trabajo presentado en EuropaCat: 11th European Congress on Catalysis, celebrado en Lyon (Francia) del 1 al 6 de septiembre de 2013.

Trabajo presentado en el Congreso de la Sociedad Española de Catálisis SECAT 13, celebrado en Sevilla (España) del 26 al 28 de junio de 2013., Los catalizadores más empleados en la reacción de reformado seco de metano son los que emplean Ni como fase activa pero presentan el inconveniente de desactivarse por formación de carbono [1]. Catalizadores derivados del precursor tipo hidrotalcita han mostrado mejoras significativas en la estabilidad en esta reacción puesto que presentan alta dispersión de las partículas metálicas, alta área superficial y son básicos lo que favorece la quimisorción de CO2 [2]. Para mejorar la resistencia a la formación de carbono, se adicionó La que aumenta la dispersión de níquel, mejora la adsorción de CO2 y retrasa la sinterización de la fase activa [3]. Existen diversos métodos de preparación de hidrotalcitas, siendo la coprecipitación el método más empleado [4]. Las condiciones de síntesis más comúnmente utilizadas son pH entre 7 y 10 y temperaturas entre 60 y 80 ºC [3]. El objetivo de este trabajo es estudiar la influencia del pH de síntesis sobre la actividad y estabilidad de un catalizador derivado de la estructura hidrotalcita en la reacción de reformado seco de metano., Este trabajo ha sido financiado por la Comunidad de Madrid (Programa DIVERCEL-CM, S2009/ENE-1475).

270 páginas, 78 tablas y 135 figuras, El objetivo de este trabajo ha sido el desarrollo de catalizadores derivados de la estructura hidrotalcita, que permitan la obtención de hidrógeno a partir de biogás mediante la reacción de reformado de metano con dióxido de carbono. Se han considerado tres variables a estudiar en el diseño de catalizadores: el contenido en lantano, la temperatura de calcinación y la relación molar Mg/Al. Tanto los precursores, como los catalizadores sintetizados a partir de ellos, fueron caracterizados por diversas técnicas físico-químicas para determinar la influencia que cada una de esas variables ejerce sus propiedades composicionales, texturales y estructurales. Los catalizadores fueron evaluados en la reacción de reformado de metano con dióxido de carbono en diversas condiciones de reacción, estudiando el comportamiento de cada uno de ellos en función de sus propiedades físico-químicas. Con el catalizador que presentó mejores prestaciones en cuanto a actividad, selectividad y estabilidad (LaHT3), se llevó a cabo un estudio de la influencia de diversas variables de operación (velocidad espacial, temperatura de reacción, composición de la alimentación) con objeto de optimizar las condiciones de reacción. Finalmente, se llevaron a cabo ensayos de larga duración y posterior caracterización para evaluar la estabilidad y resistencia a la desactivación.

Tesis doctoral inédita, leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Química Física Aplicada. Fecha de lectura: 26-06-2012

Hydrotalcite-like precursors have been synthesized in order to study the influence of lanthanum on the structure and the properties of the precursors, as well as on the catalytic activity and stability of their derived catalyst on biogas reforming. From XRD, and TPO characterization, we confirmed that hydrotalcite-like precursors where obtained. After calcination at 750 ºC, Mg (Ni,Al)O solid solution was detected. High surface areas have been obtained finding the highest surface area on the catalyst without lanthanum. TPR experiments were performed in order to study the reducibility of the catalysts. One reduction peak was found in the catalyst without lanthanum while two peaks were observed in the catalysts with lanthanum. A reduction peak at 900 ºC was observed over the sample without Ni and La. Catalytic tests, at 700 ºC with a feed of CH4:CO2 1:1, were performed after appropriate reduction during 50h. While a decrease on catalytic activity was observed with the addition and the increase of La content, an enhancement in the stability was observed. No sign of deactivation of the catalyst and no carbon deposition were found on the catalysts doped with lanthanum., Financial support from Comunidad de Madrid (DIVERCEL-CM, S2009/ENE-1475) and CDTI (CENIT 2007-1039) is gratefully acknowledged.

Hydrotalcite-like compound with general formula [M(II)1-xM(III)x(OH)2]x+(An-x/n) . mH2O, where An- is the compensation anion, has been used as precursor of active catalysts for biogas reforming. This precursor was calcined at six different temperatures between 250 and 750 ºC and the resulting catalysts were tested in order to evaluate the influence of the calcination temperature on the catalytic activity and stability. XRD characterization showed that from 250 ºC the hydrotalcite structure is no longer detected, leading to Mg(Ni,Al)O solid solutions, where no peaks related to lanthanum appear. An increase on the calcination temperature increased the grain size and cell parameter value. 50h-catalytic tests were carried out at 700 ºC, CH4:CO2 molar ratio of 1:1 and a mass/feed alimentation ratio (W/F) of 0.4 mg·min·cm-3. Used catalysts were characterized by temperature programmed oxidation (TPO), scanning electron microscopy (SEM) and Raman spectroscopy in order to obtain information about coke deposition. Catalytic tests highlighted the great influence of calcination temperature over catalytic activity and stability, having found that, as a general trend, calcination temperatures below 750 ºC decrease both the stability and catalytic activity, with the exception of the catalyst calcined at 550 ºC, where a higher activity was achieved but with a comparatively low stability., Financial support from Comunidad de Madrid (DIVERCEL-CM, S2009/ENE-1475) and CDTI (CENIT 2007-1039) is gratefully acknowledged. The authors thank Dr. M.A. Bañares, R. López-Medina and E. M. Mikolajska from Instituto de Catálisis (CSIC) for his help with Raman analysis and their helpful discussions.