Mixed matrix membranes

In recent decades, mixed matrix membranes (MMMs) have attracted considerable interest in research laboratories worldwide, motivated by the gap between the growing interest in developing novel mixed matrix membranes by various research groups and the lack of large-scale implementation. This Special Issue contains six publications dealing with the current opportunities and challenges of mixed matrix membranes development and applications as solutions for the environmental and health challenges of 21st century society.Financial support by the Spanish Ministry for Science and Universities under project grant no. CTQ2016-76231-C2-1-R at the Universidad de Cantabria is gratefully acknowledged

Análisis y evaluación matemática en Educación Infantil: estudio de los componentes relacionales

El presente documento conlleva una contextualización, así como una puesta en práctica y posterior análisis del Test de Evaluación de Matemática Temprana (TEMT). Mediante la consulta de diferentes fuentes bibliográficas relacionadas con el tema de trabajo, podemos abordar conceptos que hacen referencia al desarrollo cognitivo del niño y a la competencia matemática temprana. El eje central del estudio es la puesta en práctica del TEMT para evaluar la competencia matemática adquirida por una muestra de alumnos en la etapa infantil. A través de la recogida de datos y el análisis de resultados, se propone una discusión y conclusiones de los mismos, así como del test y la realización del documento. Además, se plantean una serie de limitaciones y propuestas de mejora con respecto a la puesta en práctica del TEMT.Grado en Educación Infanti

Análisis del contenido curricular de biología en el segundo ciclo de Educación Infantil

En este trabajo se habla de la Biología, como ciencia en desarrollo; en el cual, se exponen algunos aspectos de dicha ciencia, así como su importancia sobre contenidos curriculares en el 2º Ciclo de Educación Infantil ya que acerca al niño a la realidad de su cotidianeidad, por lo que es imprescindible trabajarla desde la más temprana infancia utilizando las herramientas necesarias.Para ello, se ha llevado a cabo un Plan de Intervención que consta de actividades dirigidas para desarrollar distintos aspectos de la Biología centrándose concretamente en los animales salvajes, siendo éste uno de los contenidos principales del Currículum. Es importante ser conscientes de los grandes beneficios que nos puede aportar la Biología para que desde Infantil en adelante se siga trabajando de una manera adecuada, puesto que en la puesta en práctica de esta propuesta se han obtenido unos buenos resultados que cumplen con los objetivos propuestosGrado en Educación Infanti

Chitosan: polyvinyl alcohol based mixed matrix sustainable coatings for reusing composite membranes in water treatment: fouling characterization

This work aims at studying the potential of modifying the surface of used polyamide (PA) reverse osmosis (RO) commercial membranes by coatings made of renewable and biodegradable polymers, chitosan (CS) and polyvinyl alcohol (PVA), filled with Cu-ion-exchange layered AM-4 titanosilicate and UZAR-S3 stannosilicate to provide antifouling properties and enlarging life time of thin-film composite (TFC) membranes. The water permeation and fouling ratios were evaluated as a function of active layer material in the presence of model organic (BSA) and inorganic (NaCl) foulants. The mixed matrix membrane (MMM) coatings added on the active surface of the PA commercial membranes generally decreased the flux decline and increased the permeate flow recovery rate. The CS:PVA based coatings promote the reversible and not the irreversible fouling, especially CuAM-4CS:PVA. Beside, ATR-FTIR confirms the reversible nature of the BSA fouling and the irreversible nature of the NaCl fouling. These results may in the future open the possibility of renewing the useful lifetime of commercial RO membranes by a simple coating method in the light of the circular economy.Financial support from the Spanish Ministry of Science and Innovation under project PID2019-108136RB-C31 /AEI/10.13039/501100011033. MCIN/AEI/10.13039/501100011033 and the “European Union Next Generation EU/PRTR” for the Grant EIN2020-112319/AEI/10.13039/501100011033 are gratefully acknowledged. The Early Stage Researcher grant PRE2020-09765, funded by MCIN/AEI/ 10.13039/501100011033, is also thanked (A.T.C.)

Effect of water and organic pollutant in CO2/CH4 separation using hydrophilic and hydrophobic composite membranes

Membrane technology is a simple and energy-conservative separation option that is considered to be a green alternative for CO2 capture processes. However, commercially available membranes still face challenges regarding water and chemical resistance. In this study, the effect of water and organic contaminants in the feed stream on the CO2/CH4 separation performance is evaluated as a function of the hydrophilic and permselective features of the top layer of the membrane. The membranes were a commercial hydrophobic membrane with a polydimethylsiloxane (PDMS) top layer (Sulzer Chemtech) and a hydrophilic flat composite membrane with a hydrophilic [emim][ac] ionic liquid–chitosan (IL–CS) thin layer on a commercial polyethersulfone (PES) support developed in our laboratory. Both membranes were immersed in NaOH 1M solutions and washed thoroughly before characterization. The CO2 permeance was similar for both NaOH-treated membranes in the whole range of feed concentration (up to 250 GPU). The presence of water vapor and organic impurities of the feed gas largely affects the gas permeance through the hydrophobic PDMS membrane, while the behavior of the hydrophilic IL–CS/PES membranes is scarcely affected. The effects of the interaction of the contaminants in the membrane selective layer are being further evaluated.This research was funded by the Spanish Ministry of Science and Innovation; project CTQ2016-76231-C2-(AEI/FEDER, UE) and project PID2019-108136RB-C31)

Multiobjective optimization based on "distance-to-target" approach of membrane units for separation of CO2/CH4

The effective separation of CO2 and CH4 mixtures is essential for many applications, such as biogas upgrading, natural gas sweetening or enhanced oil recovery. Membrane separations can contribute greatly in these tasks, and innovative membrane materials are being developed for this gas separation. The aim of this work is the evaluation of the potential of two types of highly CO2-permeable membranes (modified commercial polydimethylsiloxane and non-commercial ionic liquid–chitosan composite membranes) whose selective layers possess different hydrophobic and hydrophilic characteristics for the separation of CO2/CH4 mixtures. The study of the technical performance of the selected membranes can provide a better understanding of their potentiality. The optimization of the performance of hollow fiber modules for both types of membranes was carried out by a “distance-to-target” approach that considered multiple objectives related to the purities and recovery of both gases. The results demonstrated that the ionic liquid–chitosan composite membranes improved the performance of other innovative membranes, with purity and recovery percentage values of 86 and 95%, respectively, for CO2 in the permeate stream, and 97 and 92% for CH4 in the retentate stream. The developed multiobjective optimization allowed for the determination of the optimal process design and performance parameters, such as the membrane area, pressure ratio and stage cut required to achieve maximum values for component separation in terms of purity and recovery. Since the purities and recoveries obtained were not enough to fulfill the requirements imposed on CO2 and CH4 streams to be directly valorized, the design of more complex multi-stage separation systems was also proposed by the application of this optimization methodology, which is considered as a useful tool to advance the implementation of the membrane separation processes.This work was funded by the Spanish Ministry of Science and Innovation Project PID2019-108136RB-C31/AEI/10.13039/501100011033. MCIN/AEI/10.13039/501100011033 and the “European Union NextGeneration EU/PRTR” are also thanked for the Grant EIN2020-112319/AEI/10.13039/501100011033

How to calculate number of samples in the design of pre/pro-biotics studies (metagenomic studies)

Podeu consultar el III Workshop anual INSA-UB complet a: http://hdl.handle.net/2445/118993Sessió 2. Pòster núm. 2

El desarrollo de la empatía hacia los animales y los procesos de convivencia intercultural en Educación Infantil

El presente Trabajo Fin de Grado (TFG), surge como una propuesta de inicio a la investigación que, a su vez, forma parte de una propuesta de intervención didáctica en el aula. El objetivo fundamental se centra en el desarrollo de la empatía hacia los animales y cómo ésta, genera procesos de convivencia intercultural. Desde esta perspectiva, hemos observado que muchos investigadores plantean una relación entre el maltrato hacia los animales como génesis de una posterior violencia hacia las personas. Es por ello, por lo que vamos a intentar generar, desde las etapas más tempranas de la formación de la persona, actitudes y valores que estimulen la tolerancia, el respeto, el trabajo colaborativo… a través del eje transversal de la empatía hacia los animales y el medio que los rodea. Por esta razón, desarrollaremos el TFG en la etapa de Educación Infantil (5 años).Grado en Educación Infanti

Use of Chitosan as Copper Binder in the Continuous Electrochemical Reduction of CO2 to Ethylene in Alkaline Medium

This work explores the potential of novel renewable materials in electrode fabrication for the electrochemical conversion of carbon dioxide (CO2) to ethylene in alkaline media. In this regard, the use of the renewable chitosan (CS) biopolymer as ion-exchange binder of the copper (Cu) electrocatalyst nanoparticles (NPs) is compared with commercial anion-exchange binders Sustainion and Fumion on the fabrication of gas diffusion electrodes (GDEs) for the electrochemical reduction of carbon dioxide (CO2R) in an alkaline medium. They were tested in membrane electrode assemblies (MEAs), where selectivity to ethylene (C2H4) increased when using the Cu:CS GDE compared to the Cu:Sustainion and Cu:Fumion GDEs, respectively, with a Faradaic efficiency (FE) of 93.7% at 10 mA cm−2 and a cell potential of −1.9 V, with a C2H4 production rate of 420 µmol m−2 s−1 for the Cu:CS GDE. Upon increasing current density to 90 mA cm−2, however, the production rate of the Cu:CS GDE rose to 509 µmol/m2s but the FE dropped to 69% due to increasing hydrogen evolution reaction (HER) competition. The control of mass transport limitations by tuning up the membrane overlayer properties in membrane coated electrodes (MCE) prepared by coating a CS-based membrane over the Cu:CS GDE enhanced its selectivity to C2H4 to a FE of 98% at 10 mA cm−2 with negligible competing HER. The concentration of carbon monoxide was below the experimental detection limit irrespective of the current density, with no CO2 crossover to the anodic compartment. This study suggests there may be potential in sustainable alernatives to fossil-based or perfluorinated materials in ion-exchange membrane and electrode fabrication, which constitute a step forward towards decarbonization in the circular economy perspective.This research was funded by the Spanish Ministry for Science and Innovation, grant numbers PID2019-108136RB-C31, PID2019-108136RB-C32, PID2020-112845RB-I00 and EIN2020-112319. A.M.M. also acknowledges the Ministry for the Early Stage researcher contract (FPI grant no. BES-2017-080795)

Effect of humidity on CO2/N2 and CO2/CH4 separation using novel robust mixed matrix composite hollow fiber membranes: experimental and model evaluation

In this work, the performance of new robust mixed matrix composite hollow fiber (MMCHF) membranes with a different selective layer composition is evaluated in the absence and presence of water vapor in CO2/N2 and CO2/CH4 separation. The selective layer of these membranes is made of highly permeable hydrophobic poly(trimethyl-1-silylpropine) (PTMSP) and hydrophilic chitosan-ionic liquid (IL-CS) hybrid matrices, respectively, filled with hydrophilic zeolite 4A particles in the first case and HKUST-1 nanoparticles in the second, coated over compatible supports. The effect of water vapor in the feed or using a commercial hydrophobic PDMSXA-10 HF membrane has also been studied for comparison. Mixed gas separation experiments were performed at values of 0 and 50% relative humidity (RH) in the feed and varying CO2 concentration in N2 and CH4, respectively. The performance has been validated by a simple mathematical model considering the effect of temperature and relative humidity on membrane permeability.This research was funded by the Spanish Ministry of Science, Innovation and Universities (www.ciencia.gob.es) under project CTQ2016-76231-C2-1-R