Cu-CHA material efficient in the SCR process in the presence of water and CO2

A reproducible method for the synthesis of SCR active Cu-CHA materials has been developed, which allows the incorporation of up to 4% of copper inside the cavities of the zeolite. These materials are highly efficient in the removal of NOx by reaction with ammonia, even in the presence of water and CO2 in the reaction atmosphere. Cu2+ species are the active species in the reaction and in contact with water and CO2, the hydrated-carbonate Cu2+ species placed in the 8-rings were identified as the responsible for the improvement in the activity.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Intensification of methanol steam reforming process using Cu-modified Ni-based supported catalysts

Hydrogen is conventionally manufactured in large scale by the steam reforming of methane or naphthas. The perspective of using hydrogen as a fuel depends of finding alternatives to the existing production technologies and feedstock. Oxygenated compounds are an interesting alternative and are been investigated extensively. The process of steam reforming of mixtures of oxygenated hydrocarbons does not contribute to a net increase in atmospheric CO2, as oxygenated obtained from renewable resources are considered to be CO2 neutral. In previous works has been demonstrate that Steam Reforming of oxygenated compounds is a complex reactions network where in a previous step, decomposition reaction take place followed by the reforming of decomposition products. Its known that DME (or methanol) receives particular attention due to its properties similar to those of liquefied petroleum gas (LPG)and it can be used as a clean high-efficiency compression ignition fuel. In other way, it has been demonstrate that DME-SR to produce H2 occurs through two main reactions in series, DME-Hydrolysis and MeOH-Steam Reforming. Therefore, bifunctional catalysts are necessary, with and acid funcion active in DME-HYD and a redox for reforming step. On the other hand, methanol is also regarded as an important feedstock for hydrogen production due to its high energy density and superior transportability, especially for small-scaled and portable fuel cell applications. In comparison with CH4-SR, the reaction temperature of methanol steam reforming is much lower and the gas off contains typically 60%-70% H2. In this contribution the Steam Reforming of MeOH has been studied using a Ni-based supported catalysts modified with copper and an optimized formulation was considered to incorporate in a microreformer, as an intensification of process to direct hydrogen supply on board.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Bi-reforming of Biogas for Hydrogen Production with Sulfur-Resistant Multimetallic Catalyst

A multimetallic sample, NiCeSnRh/Al2O3, was tested in methane reforming with a CH4:H2O:CO2 molar ratio equal to 3:2:1. A very stable methane conversion with the time-on-stream was achieved during 20 h. Dimethyl sulfide served as a model sulfur molecule and a sulfurized sample was also tested. This achieved slightly lower conversion with a stable performance for more than 10 h and a minor but continuous decrease of its activity, after this period. The carbon dioxide conversion was always higher than the methane conversion in agreement with the lower H2/CO ratio observed with respect to the theoretical value, 2/1, indicating the sulfur might block the active sites for H2O activation. The analysis of the used catalysts showed graphitic and disordered carbon depositsFunding for open access charge: Universidad de Málaga/CBUA

Hacia la diversificación energética: Bioenergía

La apuesta por la sostenibilidad, el aumento de la producción interna, la exploración de otras fuentes de energía y, en la medida de lo posible, la conservación de recursos son una receta a tener en cuenta para reducir facotres como la contaminación y evitar además la excesiva dependencia externa

Performance analysis of isostructural Cu-CHA-zeolites in NSR-SCR Hybrid DeNOx Technology for Diesel Engines.

_Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Comparison of Cu-CHA-zeolites in the hybrid NSR-SCR catalytic system for NOx abatement in mobile sources

DeNOx activity in a NSR–SCR hybrid system of two copper-containing chabazite-type zeolitic catalysts was addressed. A Pt-Ba-K/Al2O3 model catalyst was used as the NSR (NOx storage and reduction) catalyst. For the SCR (selective catalytic reduction) system, two Cu-CHA zeolites were synthesized employing a single hydrothermal synthesis method assisted with ultrasound and incorporating Cu in a 2 wt.%, 2Cu-SAPO-34 and 2Cu-SSZ-13. The prepared catalysts were characterized, and the crystallinity, surface area, pore size, HR-TEM and EDX mapping, coordination of Cu ions and acidity were compared. The NH3 storage capacity of the SCR catalysts was 1890 and 837 μmol NH3·g−1cat for 2Cu-SAPO-34 and 2Cu-SSZ-13, respectively. DeNOx activity was evaluated for the single NSR system and the double-bed NSR–SCR by employing alternating lean (3%O2) and rich (1%H2) cycles, maintaining a concentration of 600 ppm NO, 1.5% H2O and 0.3% CO2 between 200 and 350 °C. The addition of the SCR system downstream of the NSR catalyst significantly improved NOx conversion mainly at low temperature, maintaining the selectivity to N2 above 80% and reaching values above 90% at 250 °C when the 2Cu-SSZ-13 catalyst was located. The total reduction in the production of NH3 and ~2% of N2O was observed when comparing the NSR–SCR configuration with the single NSR catalyst.SMR acknowledges the Economy and Competitiveness Spanish Ministry for the Ph.D. grant (PRE-2018-086107). Authors want to thank the financial support of CTQ 2017-87909-R Project from the Economy and Competitiveness Spanish Ministry. Partial funding for open access charge: Universidad de Málag

Estudio del proceso cíclico de captura y conversión de CO2 en corrientes enriquecidas en H2 empleando CH4 con un catalizador NiBa no soportado

El principal objetivo decidido en el Acuerdo de París de 2015 fue el de mantener el aumento de la temperatura media mundial por debajo de 2C respecto a los niveles en la era preindustrial. La reducción de la concentración de CO2 (GEI, gases de efecto invernadero) en la atmósfera es urgente debido al continuo y sostenido aumento (>410 ppm enero de 2019) y su impacto negativo e incluso irreversible en el sistema climático. El abatimiento de CO2 se puede conseguir a través de tres vías: control de las emisiones, captura y almacenamiento, y conversión química y utilización del CO2. Las tecnologías de captura y almacenamiento de CO2 son una alternativa y existen materiales funcionalizados capaces de adsorber CO2 como las zeolitas, carbones activos, aminas terciarias, hidrotalcitas, MOFs, etc. siendo no solo el alta área superficial y volumen de poro, sino también las propiedades químicas del material parámetros clave para actuar como adsorbente. Sin embargo, las tecnologías que combinan la captura y conversión de CO2, exige un desarrollo de catalizadores de doble función1. En esta contribución se presentan algunos datos correspondientes al desarrollo de un nuevo catalizador bimetálico no soportado, tipo Ni-Ba, capaz de operar en régimen transitorio y cíclico, alternado una etapa de almacenamiento del CO2 contenido en corrientes de gas de escape y una segunda etapa de regeneración del catalizador a través de la inyección de pulsos de metano y la producción de corrientes enriquecidas de hidrógeno (syngas) por reformado seco in situ preferencial.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Ni-Ga no soportado como catalizador para la hidrogenación de CO2 a presión atmosférica

Debido al continuo aumento de las emisiones de CO2 y su efecto negativo desde el punto de vista mediambiental y de salud, se debe proponer acciones encaminadas a su control. Es de interés la captura y conversión química obteniendo productos de valor añadido. Destaca la hidrogenación de CO2, a partir de H2 renovable con catalizadores que permitan la hidrogenación en condiciones suaves de operación; concretamente en esta contribución se muestran los resultados obtenidos con un catalizador Ni/Ga sintetizado y caracterizado en el grupo de investigación PROCAT del Departamento de Ingeniería Química de la UMA, analizando la capacidad hidrogenante en función de la velocidad espacial, relaciones de alimentación H2/CO2 y la Temperatura, obteniéndose conversiones en torno al 40% y selectividades a CO del 95%.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Incorporation of an alkaline-alkaline earth metal in an unsupported bimetallic Ni-containing catalyst for the CO2-SR technology.

Introduction. In the past decades, global warming resulting from the emission of greenhouse gases, consisting mainly of carbon dioxide and methane, has become one of society’s main concerns. In this context, there has been a growing interest in developing technologies that allow the capture and storage of CO2 in an economical and sustainable way. The application of a heterogeneous bimetallic nickel-barium catalyst as a dual material has been studied for its use in the CO2 regeneration cyclic process. The present work shows the data corresponding to the substitution of Ba by Ca or Sr and K as a bimetallic catalytic systems to analyse the structural and physicochemical properties and the effect on CO2 storage capacity. Experimental/methodology. The catalysts were synthesised by an ultrasonic assisted coprecipitation of the heterometallic mixed precursors employing an atomic ratio Ni:Me = 1:1 using colloidal silica as surface area promoting agent, and calcined at 800 °C in air for 4 h. X-ray diffraction (XRD), KBr-FTIR infrared, Raman spectroscopy and nitrogen adsorption-desorption were employed for the characterisation. The CO2 adsorption capacity was analysed at low temperature and at high reaction temperature. Results and discussion. The influence of the incorporation of the metal in combination with nickel has been studied and it has been found that, even at high temperature, it maintains a cubic structure with a surface area higher than 80 m2·g-1. The crystal size of bivalent or monovalent cation was not affected by the modification of the catalytic formulation. There is a correlation between CO2 adsorption capacitity and the electronegativity of the second metal incorporated to the nickel structure.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Heterogeneización del proceso continuo para la conversión de glicerol a Solketal utilizando un catalizador estructurado monolítico de base carbonosa

Se ha desarrollado un catalizador estructurado de base carbonos hidrofobia y funcionalidad con grupos sulfúricos estables no lixiviables que permite la operación en continuo de la acetalización de glicerol con acetona de forma eficiente y se han establecido los parámetros operacionales y espaciales para su posible escalado.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech