Person:
Rodríguez Rodríguez, Araceli

First Name

Araceli

Last Name

Rodríguez Rodríguez

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Químicas

Department

Ingeniería Química y de Materiales

Area

Ingeniería Química

Identifiers

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Now showing 1 - 10 of 17

Mesoporous low silica X (MLSX) zeolite: Mesoporosity in loewenstein limit?
(Elsevier, 2022-12) Gómez Martín, José María; Montes, Ignacio; Díez Alcántara, Eduardo; Rodríguez Rodríguez, Araceli
Synthesis of Low Silica X zeolite (LSX) with hierarchical porosity was achieved. The low silicon/aluminum ratio of this zeolite allowed to increase the number of active sites, as cationic positions (>25%) respect to the previous mesoporous X zeolite. Mesoporosity was induced by using sodium dodecylbenzene sulfonate (SDBS) during the synthesis. A dissolution time of 24 h for SDBS improved the zeolite crystallinity, maintaining the FAU characteristic framework, with a silicon/aluminum molar ratio near the unity (<1.1), limit of the Lowenstein’ rule. The surfactant removal at 773 K promoted the development of a wider pore size distribution. The heating rate highly determined the pore size distribution, resulting in a bimodal distribution (maxima at 80 Å and 290 Å) at low heating rate (1.3 K/min) and a unimodal distribution, with a maximum at 230 Å, at higher heating rate (8 K/min). The analysis by Transmission Electronic Microscopy (TEM) showed the mesoporous cavities in the zeolite nanoparticles. These cavities were generated by the SDBS spherical micelles removal. Mesoporous Low Silica X zeolite (MLSX) showed higher catalytic activity than the same zeolite without mesoporosity in the deoxygenation of oleic acid. The conversion reached a constant value around 100% with higher yield toward C9–C18 hydrocarbons, representative fraction of sustainable aviation fuel (SAF). Therefore, this new mesoporous low silica X zeolite (MLSX) has a significant potential use as catalyst in the processing of bulky molecules.
Hacia la convergencia europea en las enseñanzas de ingeniería química: operaciones con sólidos en el campus virtual
(Editorial Complutense, 2005) Rodríguez Rodríguez, Araceli; Sotelo Sancho, José Luis; Gómez Martín, José María; García Rodríguez, Juan; Grupo de Catálisis y Operaciones de Separación (CyOS), Facultad de Ciencias Químicas - UCM; Fernández-Valmayor Crespo, Alfredo; Fernández-Pampillón Cesteros, Ana María; Merino Granizo, Jorge
La asignatura optativa de tercer curso del Título de Ingeniero Químico «Operaciones con Sólidos» participa durante este curso académico en el grupo piloto de adaptación al Espacio Europeo de Educación Superior (EEES). Para el desarrollo de esta asignatura de acuerdo con las directrices de Convergencia Europea ha sido de gran ayuda el Campus Virtual, como apoyo a las clases presenciales, herramienta de evaluación continua, espacio de trabajo en grupos y de comunicación en la clase.
Desarrollo de materiales y herramientas para la aplicación de aula inversa, aprendizaje colaborativo y autoaprendizaje en asignaturas del Grado y Máster en Ingeniería Químicas
(2019-06-25) Rodríguez Rodríguez, Araceli; Díez Alcántara, Eduardo; Gómez Martín, José María; Sáez González, Patricia; Bernabé Virseda, Ignacio; Díaz Moreno, Ismael
El objetivo del proyecto es desarrollar materiales (hojas de cálculo, apuntes, encuestas) que permitan una implantación de metodologías basadas en aula inversa y aprendizaje cooperativo en las asignaturas Operaciones con Sólidos y Mecánica de Fluidos.
Sequential separation of cobalt and lithium by sorption: Sorbent set selection
(Elsevier, 2022-09-24) Conte Erustes, Naby; Gómez Martín, José María; Díez Alcántara, Eduardo; Sáez González, Patricia; Monago García, José Ignacio; Espinosa, Anna; Rodríguez Rodríguez, Araceli
The sorption of cobalt and lithium was studied using low-cost natural (dolomite, diatomite, barite), commercial (13X zeolites and clinoptilolite) and synthesized (mesoporous carbon and NaY zeolite) sorbents. The pH of the medium was a key factor in the sorption process which can be modified due to the active chemical groups on the surface of the sorbents. Therefore, the doses of each sorbent were selected to avoid cobalt precipitation, working at pH below 8. Sorption with monometallic solution was carried out to select the best set of sorbents for subsequent selective separation. Only mesoporous activated carbon and dolomite allow to achieve significant cobalt removal, 85% and 65% respectively, with negligible lithium removal. 13X zeolite (high surface area and low Si/ Al molar ratio) removed both metals without selectivity. Therefore, dolomite and mesoporous activated carbon were selected for the selective separation of cobalt, as they allow to achieve an adsorbed Co2+/Li+ weight ratio of 16 and 4, respectively. 13X was selected to remove lithium once cobalt was removed from the solution. The best separation was carried out by a two-sequential sorption stage, using dolomite in a first stage to separate cobalt and 13X zeolite in a second stage to remove lithium, reaching an almost complete removal of both metals. The pH control for working with high doses of dolomite was achieved by means of a solid phase pH buffer (solid buffer) composed by a mixture of the dolomite itself and non-activated mesoporous carbon (without sorption capacity) in a 1:4 weight ratio. This solid buffer allowed the pH of the medium to be controlled to around 6.5.
Hidroisomerización de n-decano con catalizadores Ni-ZSM-5
(Universidad Complutense de Madrid, Servicio de Publicaciones, 2002) Rodríguez Rodríguez, Araceli; Romero Díaz, María Dolores
La hidroisomerizacion catalica de parafinas lineales, es en la actualidad un proceso atractivo para aumentar el índice de octano de las gasolinas o mejorar las propiedades fluidodinamicas de los aceites lubricantes.en esta sentido, la obtención de catalizadores bifuncionales basados en zeolita zsm-5 y níquel resulta de gran interés debido a su selectividad de forma ya que isomerizan solo las parafinas lineales, dejando inalteradas las moléculas ramificadas.en este campo se encuadra la tesis doctoral de d. Araceli Rodríguez, que ha consistido básicamente en el estudio de estos catalizadores bifuncionales. En primer lugar se ha abordado la influencia de la técnica de introducción del metal: mezcla física, intercambio iónico en estado liquido y solidó e impregnación, llegándose a la conclusión de que los catalizadores preparados por impregnación conducen a mejores conversiones y selectividades en la hidroisomerizacion de n-decano. En estos catalizadores se ha estudiado la influencia de las variables de las etapas de preparación, tales como secado, calcinación y reducción, asi como la influencia de la relación centros metálicos/ácidos (contenidos de metal y si/al de la zeolita) todos los catalizadores se han caracterizado mediante las técnicas de: tpd, tpr, tf, dtg, aa, xrd, xps, sem, etc...
Effect of cerium (IV) on thin sulfuric acid anodizing of 2024-T3 alloy
(Elsevier Science BV, 2021-10-07) Olmo, R. del; Mohedano Sánchez, Marta; Visser, P.; Rodríguez Rodríguez, Araceli; Matykina, E.; Arrabal Durán, Raúl
Chromic acid anodizing (CAA) is still being used today for corrosion protection of fatigue-critical components in the aeronautic industry due to the lack of feasible alternatives. Ce-containing sulfuric acid anodizing (SAA) has been identified as a promising strategy for the development of alternatives to toxic CAA. This work explores thin sulfuric acid anodizing (TSAA) focusing on the following effects: (i) current density and voltage values; (ii) concentration of Ce(IV). Screening of the optimum combination in search of minimum thickness and the best corrosion resistance was performed using electrochemical impedance spectroscopy (EIS). Two Ce-containing anodic films were selected and further investigated in comparison with the inhibitor-free film in terms of morphology (FEG-SEM, TEM), composition (RBS), corrosion resistance (EIS, NSST), high-cycle fatigue and paint adhesion. The results indicate that the path to approach the CAA performance lies through thin (<1 μm) SAA-Ce films formed at low current density.
Sustainable Recovery of Cobalt from Aqueous Solutions Using an Optimized Mesoporous Carbon
(Springer, 2023-01-10) Conte Erustes, Naby; Díez Alcántara, Eduardo; Almendras, Brigitte; Gómez Martín, José María; Rodríguez Rodríguez, Araceli
The aim of this paper is to employ a factorial design to optimize the activation step in the synthesis process of a mesoporous-activated carbon to be used as adsorbent for removing and recovering cobalt ions from aqueous solutions. This activation has been carried out in a tubular furnace in the presence of an air stream, following a 23 factorial design. According to the obtained results, the best activation conditions to reach a maximum cobalt removal are mild conditions, low activation temperatures and large times, while the air flow seems to be positive influence working in a low level. This is due to the enhancement of superficial oxygenated groups formation in these conditions, responsible of the adsorption process. The kinetic curve obtained for the adsorbent prepared at the most favorable conditions showed that the adsorption process was very fast and efficient, reaching equilibrium in 15 min, and was properly described by a pseudo-second-order kinetic, typical of the processes in which there are no diffusion limitations. Additionally, with the aim of studying the potential of metal recovery, desorption studies were performed. Sulfuric acid as stripping agent led to twofold Co preconcentration ratio, by reducing the desorption volume to the quarter.
Inmersión de los estudiantes de Ingeniería Química en un mundo laboral determinado por los ODS mediante aprendizaje basado en el caso con un mentor del ámbito industrial
(2022) Díez Alcántara, Eduardo; Díaz Moreno, Ismael; Gómez Martín, José María; Gómez Sánchez, Adrián Casimiro; González Gómez, Emilio José; Guerrero Moreno, Elisa; Leal García, José Luis; Moreno Gómez, Andrea; Ramos Irala, Santiago; Redondo Soto, Cinthya; Rodríguez Rodríguez, Araceli
El objetivo es utilizar el aprendizaje basado en el caso en la asignatura "Operaciones con sólidos" para acercar a los estudiantes a la realidad industrial determinada por la sostenibilidad, mediante un caso práctico con la participación de un mentor del ámbito industrial.
Experiencia en el espacio europeo en educación superior con el laboratorio de Ingeniería Química I
(Editorial Complutense, 2005) Ovejero Escudero, Gabriel; Romero Díaz, María Dolores; Rodríguez Rodríguez, Araceli; García Rodríguez, Juan; Gómez Martín, José María; Grupo de Catálisis y Operaciones de Separación (CyOS), Facultad de Ciencias Químicas - UCM; Fernández-Valmayor Crespo, Alfredo; Fernández-Pampillón Cesteros, Ana María; Merino Granizo, Jorge
Desde el curso académico 2003-2004 el Grupo de Catálisis y Operaciones de Separación, integrado en el Departamento de Ingeniería Química, viene desarrollando la virtualización de algunas asignaturas dentro de la titulación de Ingeniero Químico con vistas a la entrada en el Espacio Europeo de Educación Superior. Dentro de esta línea, la asignatura de Laboratorio de Ingeniería Química I (LIQI), cumple su segunda experiencia en el aula virtual de la UCM. En esta comunicación presentamos la experiencia obtenida tras los dos años de puesta en marcha de la virtualización de dicha asignatura.
Zeolite Adsorbents for Selective Removal of Co(II) and Li(I) from Aqueous Solutions
(MDPI, 2023) Díez Alcántara, Eduardo; Redondo, Cinthya; Gómez Martín, José María; Miranda Carreño, Rubén; Rodríguez Rodríguez, Araceli
Cobalt and lithium are critical metals because of its shortage, difficulty of extraction and huge economic impact due to their market value. The purpose of this work is to study their selective removal from aqueous solutions in different conditions using two commercial FAU zeolites as adsorbent materials. These solids were characterized by XRD, XRF and BET analysis, to follow up of their FAU structure integrity, their Si/Al ratio, and their specific surface area evolutions through their preparation process. The kinetic study indicates that using both zeolites with a dosage of 5 g/L a 100% cobalt removal from aqueous solutions is achievable, while lithium removal is kept around 30% (separation factor of 3.33). This selectivity is important as these two metals frequently appear together in leaching solutions form, for example, ion-Li batteries. In relation to the adsorption equilibrium, cobalt adsorption presents a finite adsorption capacity while this behavior is not observed in lithium adsorption. For this reason, Langmuir model is the most adequate to represent cobalt adsorption, while lithium adsorption is better represented by Freundlich model.