Desarrollo y evaluación de materiales carbonosos derivados de biomasa como agentes de separación para la captura de CO2

El objetivo de este trabajo es el desarrollo y la evaluación de materiales que puedan actuar como agentes de separación en la captura de CO2 tanto en gases de postcombustión como en procesos de purificación de biogás para obtener gas natural renovable o biometano. Se evaluaron experimentalmente tres tipos de materiales: dos materiales carbonosos derivados de biomasa y una zeolita comercial a modo comparativo. El método de evaluación fue desarrollado en el laboratorio (desorción por lecho fijo) y permite la caracterización y la optimización de los materiales para funcionar como agentes de separación.Fil: Aráoz, María Emilse. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología; ArgentinaFil: Marcial, Adrián Facundo. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología; ArgentinaFil: Avila, Adolfo María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología; ArgentinaXXVII Jornadas de Jovens PesquisadoresSan CarlosBrasilAsociacion de Universidades Grupo MontevideoUniversidade Federal de São Carlo

Biochar material evaluation through shock electrodialysis phenomenon for sustainable separation devices

The availability of biomass associated with agroindustry residues provides enormous opportunities for new bioproducts applications for sustainable processes. Biochar is a cost-effective carbonaceous material which can serve as raw material to create new separation agents and microdevices for gas purification, water treatment, biomolecule separation, controlled drug delivery, electrochemical reactors, microseparators and many other advanced applications. In this work, we used biochar disks derived from biomass harvest residues as a porous media to study the shock electrodialysis phenomenon. A home-made cell for continuous electrolyte flow including two stainless steel electrodes was used to study this phenomenon. Comparative cyclic voltammetry measurements were performed using the cell in batch mode with 1x10-4 M KCl solution either including or not including the biochar porous media. The difference between both voltammetry profiles showed how the presence of the porous material modified the extension of the plateau zone related to the diffusion-limited current density, which allows to perform shock electrodialysis tests. A set of continuous flow runs considering both distilled water (2.0 ? 6.0 µS/cm) and 1x10-4 M KCl solution (~17 µS/cm) were performed under an applied electric potential previously selected from the voltammetry measurements. The continuous monitoring of the solution ion conductivity in the cell outlet throughout each run provided important insights. The decrease of the outlet ion conductivity when the electric potential was applied to the cell indicated the presence of ion concentration polarization through the biochar porous material. The polarization effect increased when flow velocities and electrolyte concentrations were lower. With a proper engineering design (geometry, thickness and morphology) and considering optimized operating conditions (flow rate, applied voltage and ion concentration), this cost-effective carbonaceous material may play an important role in the development of new separation technologies for water treatment.Fil: Montes, Paula. Universidad Nacional de Tucumán; ArgentinaFil: Antunez, Camila. Universidad Nacional de Tucumán; ArgentinaFil: Trujillo, Matías. Universidad Nacional de Tucumán; ArgentinaFil: Iglesias, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Trejo González, José Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Madrid, Rossana Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Avila, Adolfo María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaXXIX Interamerican Congress of Chemical EngineeringTorontoCanadáCanadian Society for Chemical Engineerin

Batch Adsorber based PSA Model for Rapid and Efficient Screening of Adsorbents in Post-Combustion CO2 Capture

The adsorption-based CO capture has shown promising potential overcoming the limitations posed by commercialised solvent amine-based systems. The choice of an adsorbent is critical to the design of pressure swing adsorption (PSA) processes. Since adsorption processes are cyclic, their design and optimization are computationally challenging. Hence, simple models that capture the essential process characteristics are required for rapid screening of adsorbents. The objective of this work is to come up with a simplified process design model for PSA process which could reliably screen the adsorbents at a faster rate. The model considers only a batch adsorber thereby significantly reducing the complexity, allowing for rapid computation. The model is used to estimate CO purity, recovery and energy consumption. The model results are compared with detailed process optimizations to develop a classification metric to identify adsorbents that satisfy U. S. Department of Energy’s requirement for CO capture processes. The model is then used to screen favourable adsorbents from a set of 100+ real and hypothetical adsorbents. The results indicate that the batch adsorber model can be used for screening a large database of adsorbents in a fast and efficient manner.Fil: Subramanian Balashankar, V.. University of Alberta; CanadáFil: De Pauw, R.. University of Alberta; CanadáFil: Rajagopalan, A. K.. University of Alberta; CanadáFil: Avila, Adolfo María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Rajendran, A.. University of Alberta; CanadáXXIX Interamerican Congress of Chemical EngineeringTorontoCanadáCanadian Society for Chemical Engineerin

Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide

On a Rational Performance Evaluation for the Development of Inorganic Membrane Technology in Gas Separation and Membrane Reactors

Inorganic membranes can be made of different materials. However, there have been only few reports on membrane evaluation to convert lab-scale membranes into a prototype for industrial applications. In order to fill this significant gap, new approaches for the development and optimization of membrane products are required. This work focuses on the different aspects related to the performance assessment of membranes used for gas separation and membrane reactors. This approach can be visualized as an algorithm consisting of three specific loops involving different aspects of the overall membrane evaluation. Several factors that have an impact on membrane performance are discussed. These factors are divided into two categories: directly affecting the measurements (setup leakage, concentration polarization, repeatability, pressure gradient) and related to the intrinsic characteristics of permeation flux across the membrane (single and mixture permeation, transport modeling, defect flux, microstructure flexibility). This evaluation protocol includes a literature review with the most recent breakthroughs in this research area.Fil: Avila, Adolfo María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Arancibia, Eleuterio Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin

Separation of ternary hydrocarbon mixtures on Y zeolite membranes

The permeation of a mixture of n-hexane, n-decane and toluene through a 40 μm Y zeolite tubular membrane on a support with negligible resistance to the mass transfer at 250 °C was modelled based on the Maxwell-Stefan formulation and the ideal adsorbed solution theory (IAST). Individual adsorption parameters were obtained with a batch fluidized bed reactor and diffusion parameters were taken from the literature. The model allowed to predict the transient fluxes and surface coverages through the membrane, showing that the responses of the components diffusing faster (n-hexane and n-decane) overshoot their steady-state values. The permeance predictions (10-8 mol/s m2 Pa) ranged from 1.2 to 20 for n-decane, from 0.4 to 4.2 for n-hexane and from 0.8 to 4.0 for toluene, according to the feed pressure and composition. The permeance selectivities, defined with n-hexane as the reference, ranged between 3 and 6 for n-decane, and between 1 and 1.8 for toluene. It was also possible to define the association between hydrocarbon coverage profiles in the membrane and the corresponding resulting fluxes.Fil: Avila, Adolfo María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Sedran, Ulises Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentin

Renewable and Electroactive Biomass-Derived Tubes for CO2Capture in Agroindustrial Processes

Tube-shaped renewable carbon materials were developed to work as separation agents for CO2 capture in agroindustrial and intensive farming facilities. The tubes have electrical properties and moderate CO2 adsorption capacities. These materials can be heated directly through the Joule effect by applying an electric potential between the ends and thus reaching temperatures higher than 473 K in a few seconds with an applied voltage of near 10 V. The tube's temperature can be easily controlled by manipulating the applied voltage, which is of interest for the development and design of CO2 capture processes through electric swing adsorption. The tubular form of the material also provides the alternative to be filled up with adsorbents like zeolite and metal-organic frameworks to produce highly selective structured adsorbents based on renewable carbon materials with the advantage of providing direct Joule heating. These materials were studied as separation agents to be part of cycles like vacuum swing adsorption, electric swing adsorption, and both combined. The tubes were tested through consecutive and repeated adsorption and Joule heating desorption experiments. The dynamics of the tube's temperature and the CO2 gas-phase composition showed consistency and repeatability. The results revealed the robustness and reliability of the biomass-derived tubes to work as separation agents for CO2 capture.Fil: Aráoz, María Emilse. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Marcial, Adrián Facundo. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Trejo González, José Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Avila, Adolfo María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin

Scalable and renewable electromembrane contactors for freshwater recovery through membrane distillation

Tube-shaped renewable carbon materials were developed from sugar cane harvest residues to work as membrane contactors for freshwater recovery from water solutions with elevated dissolved solid concentrations. The tubes have electrical properties and can be heated directly through the Joule effect by applying electric potential between the ends. Temperature increased more than linearly, which is consistent with a decrease of the tube's resistance. The Joule effect's experiments on the wet tubes showed that most of the loaded water was removed in less than 2 min for an applied voltage of 7.0 V. The tubes were tested as membrane contactors using ∼10 and ∼100 g/L NaCl solutions producing freshwater at a rate between ∼2.0 and ∼7.0 kg/m2 h with salt rejection values above 99.4%. The tested thermal conductivities of the membrane contactors were around 0.09 W/m·K, which are lower than many commercial membranes, thus making them promising in terms of the thermal efficiency of the process. These carbon tubes provide easy scalability and tolerance to corrosive and high-salinity waters, which is advantageous for water recovery from waste streams with high solute concentrations.Fil: Trejo González, José Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Aráoz, María Emilse. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Herrera, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Avila, Adolfo María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin

H2 separation using pressed clinoptilolite and mixed copper-clinoptilolite disk membranes

Disk membranes machined from high-purity natural clinoptilolite rocks demonstrated promising hydrogen separation efficiency. However, these membranes cannot be adequately scaled up. To overcome this and provide process flexibility, mixed matrix membranes are required pairing small particles of natural zeolite with a binder system. A novel approach was determined to use metals as binders and was tested by comparing natural clinoptilolite compact disk membranes with and without powdered copper metal. The phase composition and morphology of the disks were characterized and gas separation performance was evaluated using single gas permeation tests. Membrane performance was improved by applying metallic copper and copper oxide filling a portion of the inter-particle spaces and creating adhesion with the zeolite particles.Fil: Farjoo, Afrooz. University of Alberta; CanadáFil: Avila, Adolfo María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Kuznicki, Steven. University of Alberta; Canad

Caracterización de agentes de separación a partir de residuos agrícolas de cosecha (RAC): evaluación de la capacidad de adsorción de CO2 por desorción en lecho fijo

El objetivo de este trabajo es el desarrollo y la evaluación de materiales que puedan actuar como agentes de separación en la captura de CO2 tanto en gases de postcombustión como en procesos de purificación de biogás para obtener gas natural renovable o biometano. Se evaluaron experimentalmente tres tipos de materiales con técnicas de lecho fijo que permiten su desarrollo y optimización para funcionar como agentes de separación. Se puso especial énfasis en la caracterización de materiales carbonosos (biocarbón) en base a residuos de biomasa con un alto potencial para ofrecer alternativas sustentables en procesos de separación.Fil: Marcial, Adrián Facundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Aráoz, María Emilse. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Avila, Adolfo María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaXXI Congreso Argentino de Fisicoquímica y Química InorgánicaSan Miguel de TucumánArgentinaAsociación Argentina de Investigación FisoquímicaUniversidad Nacional de Tucumán. Facultad de Bioquímica Química y Farmaci