Examinando por Materia "Adsorption"
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Ítem Analysis of CO2 adsorption in amine-functionalized porous silicas by molecular simulations(American Chemical Society, 2015-06-01) Builes S.; López-Aranguren, P.; Fraile, J.; Vega, L.F.; Domingo, C.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Desarrollo y Diseño de ProcesosWe present the results of a combined experimental-molecular simulations approach concerning the capacity for CO2 adsorption of aminosilica hybrid products synthesized using supercritical fluids. Two porous supports were examined for amine functionalization, an ordered mesoporous silica (MCM-41) and a disordered silica gel (SG40). The textural properties of the studied materials were analyzed by low-temperature N2 adsorption-desorption isotherms and compared to those of molecular simulations using the grand canonical Monte Carlo simulation method. The CO2 adsorption capacity of these materials was evaluated by recording CO2 adsorption isotherms up to 100 kPa. Molecular simulations of the CO2 adsorption behavior of selected samples were performed to gain a fundamental understanding of the effect of functionalization. This study shows that in the functionalized materials, the distance between nitrogen atoms of the grafted amines is a critical factor for the occurrence of CO2 chemisorption, providing some insight into key parameters for designing adsorbent materials for CO2 capture and separation. The relationship between the adsorption results with N2 and CO2 allow us to compare the potential applications of the materials in CO2 adsorption and separation processes. A correlation of the N2 adsorption at a given pressure with the CO2 adsorption at a different pressure allowed the prediction of which materials will perform well for these processes. The hybrid products with high amine density have desirable features required for industrial sorbents, such as an enhanced CO2 adsorption capacity and selectivity. © 2015 American Chemical Society.Ítem Application of gas hydrate equilibria prediction in process engineering(Universidad EAFIT, 2014) Bonilla Vellojín, Andrés Eloyban; Schütz, Wilfried; Schmid, BastianDesde hace cerca de dos siglos, los hidratos de gas han ganado un rol importante en la ingeniería de procesos, debido a su impacto económico y ambiental en la industria -- Cada día, más compañías e ingenieros ganan interés en este tema, a medida que nuevos desafíos muestran a los hidratos de gas como un factor crucial, haciendo su estudio una solución para un futuro próximo -- Los gases de hidrato son estructuras similares al hielo, compuestos de moléculas huéspedes de agua conteniendo compuestos gaseosos -- Existen naturalmente en condiciones de presiones altas y bajas temperaturas, condiciones típicas de algunos procesos químicos y petroquímicos [1] -- Basado en el trabajo doctoral de Windmeier [2] y el trabajo doctoral the Rock [3], la descripción termodinámica de las fases de los hidratos de gas es implementada siguiendo el estado del arte de la ciencia y la tecnología -- Con ayuda del Dortmund Data Bank (DDB) y el paquete de software correspondiente (DDBSP) [26], el desempeño del método fue mejorado y comparado con una gran cantidad de datos publicados alrededor del mundo -- También, la aplicabilidad de la predicción de los hidratos de gas fue estudiada enfocada en la ingeniería de procesos, con un caso de estudio relacionado con la extracción, producción y transporte del gas natural -- Fue determinado que la predicción de los hidratos de gas es crucial en el diseño del proceso del gas natural -- Donde, en las etapas de tratamiento del gas y procesamiento de líquido no se presenta ninguna formación, en la etapa de deshidratación una temperatura mínima de 290.15 K es crítica y para la extracción y transporte el uso de inhibidores es esencial -- Una composición másica de 40% de etilenglicol fue encontrada apropiada para prevenir la formación de hidrato de gas en la extracción y una composición másica de 20% de metanol en el transporteÍtem Box-Behnken design for optimizing the acid blue dye adsorption on flower wastes(Universidad EAFIT, 2013-11-05) Jaramillo Madrid, Ana Cristina; Echavarria, Ana Maria; Hormaza, Angelina; Delft University of TechnologyÍtem A Comparative Assessment of Emerging Solvents and Adsorbents for Mitigating CO2 Emissions From the Industrial Sector by Using Molecular Modeling Tools(Frontiers Media S.A., 2020-01-01) Bahamon D.; Alkhatib I.I.I.; Alkhatib N.; Builes S.; Sinnokrot M.; Vega L.F.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Desarrollo y Diseño de ProcesosThe possibilities offered by molecular modeling tools to obtain relevant data at process conditions, while also gaining molecular insights on the techniques used for CO2 capture and separation, are presented here using selected case studies. Two different technologies, absorption with amine-based systems and adsorption on porous materials, were explored, using the molecular-based equation of state, soft-Statistical Associating Fluid Theory (SAFT), and Grand Canonical Monte Carlo simulations, respectively. The aqueous monoethanolamine (MEA) system was set as the benchmark for absorption and compared to the performance of 8 alternative amine-based systems, while 16 adsorbents belonging to different families (zeolites, metal–organic frameworks, amorphous silicas, and activated carbons), bare or functionalized with alkylamines, were investigated for the separation of CO2 by adsorption. In addition to obtaining molecular information on the CO2 capture process, the models were further used to examine the CO2 capture performance in terms of cyclic working capacity and energy index as key performance indicators, allowing the identification of promising systems that can improve the current ones to be further evaluated for separation in non-power industries. Results show that for the same total amine mass concentration, non-aqueous amine solvents have a 5–10% reduction in cyclic working capacity, and a 10–30% decrease in the energy index compared to their aqueous counterparts due to their lower heat of vaporization and specific heat capacity. In addition, M-MOF-74, NaX, and NaY structures present the best results for adsorption in temperature swing adsorption (TSA) processes. Similar values of energy requirements to those of amine-based systems (2–2.5 MJ kg CO2–1) were obtained for some of the adsorbent; however, the disadvantage of the TSA process versus absorption should be considered. These results confirm the reliability of molecular modeling as an attractive and valuable screening tool for CO2 capture and separation processes. © Copyright © 2020 Bahamon, Alkhatib, Alkhatib, Builes, Sinnokrot and Vega.Ítem Diseño de un sistema de adsorción para la separación de CO2(Universidad EAFIT, 2022) Reinoso Rojas, Aminta Elena; Bermúdez Ríos, Carlos Arturo; Builes Toro, SantiagoÍtem Efficient treatment for textile wastewater through sequential electrocoagulation, electrochemical oxidation and adsorption processes: Optimization and toxicity assessment(Elsevier BV, 2020-01-01) GilPavas E.; Dobrosz-Gómez I.; Gómez-García M.-Á.; GilPavas E.; Dobrosz-Gómez I.; Gómez-García M.-Á.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)In this work, the sequential Electrocoagulation + Electro-oxidation + Activated carbon adsorption (EC + EO + AC) process was studied as an alternative for the treatment of an industrial textile wastewater (TWW) issuing from a manufacturing company located in Medellín (Colombia). The EC's and EO's operational conditions were optimized using a Box-Behnken experimental design, the Response Surface Methodology and a constrained nonlinear optimization algorithm in terms of organic matter degradation efficiency. The best performance for EC (i. e., dye removal = 94%, COD and TOC degradation of 45 and 40%, respectively) was obtained using Fe anode and Boron Doped Diamond (BDD) cathode, with current density, jEC, equals to 5 mA/cm2, pH = 9.3, 60 RPM and 10 min of electrolysis. After EC treatment, the effluent biodegradability (evaluated as the BOD5/COD ratio) increases from 0.14 to 0.23. Regrettably, EC was not effective for the removal of acute toxicity to Artemia salina since the treated effluent remained very toxic (100%). The treatment of EC's effluent by EO enhanced organic pollutant removal. For EC + EO sequential process, EO optimal operational conditions (jEO = 10 mA/cm2, pH = 3, 240 RPM, BDD as anode and Fe as cathode) allowed reduction of 100% of color, 88% of COD and 79% of TOC after 30 min of electrolysis. Moreover, the BOD5/COD ratio increased from 0.23 to 0.58; however, the treated effluent remained very toxic to the Artemia salina. Consequently, an activated carbon adsorption step was included to complete the treatment process. Thus, by coupling the EC + EO + AC process, effluent's acute toxicity decreased completely. From molecular weight distribution analysis, it was concluded that EC + EO was efficient in eliminating low molecular weight (< 5 kDa) compounds. Finally, the operation cost, which includes chemical reagents, electrodes, energy consumption, and sludge disposal, for the EC + EO + AC sequential process was estimated in 3.83 USD /m3. © 2020 Elsevier B.V.Ítem Efficient treatment for textile wastewater through sequential electrocoagulation, electrochemical oxidation and adsorption processes: Optimization and toxicity assessment(Elsevier BV, 2020-01-01) GilPavas E.; Dobrosz-Gómez I.; Gómez-García M.-Á.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Desarrollo y Diseño de ProcesosIn this work, the sequential Electrocoagulation + Electro-oxidation + Activated carbon adsorption (EC + EO + AC) process was studied as an alternative for the treatment of an industrial textile wastewater (TWW) issuing from a manufacturing company located in Medellín (Colombia). The EC's and EO's operational conditions were optimized using a Box-Behnken experimental design, the Response Surface Methodology and a constrained nonlinear optimization algorithm in terms of organic matter degradation efficiency. The best performance for EC (i. e., dye removal = 94%, COD and TOC degradation of 45 and 40%, respectively) was obtained using Fe anode and Boron Doped Diamond (BDD) cathode, with current density, jEC, equals to 5 mA/cm2, pH = 9.3, 60 RPM and 10 min of electrolysis. After EC treatment, the effluent biodegradability (evaluated as the BOD5/COD ratio) increases from 0.14 to 0.23. Regrettably, EC was not effective for the removal of acute toxicity to Artemia salina since the treated effluent remained very toxic (100%). The treatment of EC's effluent by EO enhanced organic pollutant removal. For EC + EO sequential process, EO optimal operational conditions (jEO = 10 mA/cm2, pH = 3, 240 RPM, BDD as anode and Fe as cathode) allowed reduction of 100% of color, 88% of COD and 79% of TOC after 30 min of electrolysis. Moreover, the BOD5/COD ratio increased from 0.23 to 0.58; however, the treated effluent remained very toxic to the Artemia salina. Consequently, an activated carbon adsorption step was included to complete the treatment process. Thus, by coupling the EC + EO + AC process, effluent's acute toxicity decreased completely. From molecular weight distribution analysis, it was concluded that EC + EO was efficient in eliminating low molecular weight (< 5 kDa) compounds. Finally, the operation cost, which includes chemical reagents, electrodes, energy consumption, and sludge disposal, for the EC + EO + AC sequential process was estimated in 3.83 USD /m3. © 2020 Elsevier B.V.Ítem Optimization and toxicity assessment of a combined electrocoagulation, H2O2/Fe2+/UV and activated carbon adsorption for textile wastewater treatment(Elsevier, 2019-02-15) GilPavas, E; Dobrosz-Gomez, I; Gomez-Garcia, MA; GilPavas, E; Dobrosz-Gomez, I; Gomez-Garcia, MA; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)In this study, the potential application of sequential Electrocoagulation + Fenton (F) or Photo-Fenton (PF) + Active carbon adsorption (EC + F/PF + AC) processes were analyzed as alternatives for the treatment of an industrial textile wastewater resulting from an industrial facility located in Medellín (Colombia). In order to maximize the organic matter degradation, each step of the treatment was optimized using the Response Surface Methodology. At first, the optimal performance of EC was achieved with Fe electrodes operating at pH = 7, jEC = 10 mA/cm2 and 60 rpm, during 10 min of electrolysis. At these conditions, EC let to remove 94% of the dye's color, 56% of the COD and 54% of the TOC. Next, sequentially applied Fenton or photo-Fenton process (i.e., EC + F/PF), operating at the optimized conditions (pH = 4.3, [Fe2+] = 1.1 mM, [H2O2] = 9.7 mM, stirring velocity = 100 rpm and reaction time = 60 min.), improved the quality of the treated effluent. The EC + F let to achieve total color reduction, as well as COD and TOC removals of 72 and 75%, respectively. The EC + PF reached 100% of color, 76% of COD and 78% of TOC reductions. The EC + F/PF processes were more efficient than EC in elimination of low molecular weight (<5 kDa) compounds from wastewater. Moreover, the BOD5/COD ratio increased from 0.21 to 0.42 and from 0.21 to 0.46 using EC + F and EC + PF processes, respectively. However, EC + F/PF were not fully effective for the removal of acute toxicity to Artemia salina: 20% and 60% of reduction in toxicity using EC + F and EC + PF, respectively, comparing to very toxic (100%) raw textile wastewater. Thus, activated carbon adsorption was applied as an additional step to complete the treatment. After AC adsorption, the acute toxicity decreased to 10% and 0% using EC + F and EC + PF, respectively. The total operational costs, including chemical reagents, electrodes, energy consumption and sludge disposal, were of 1.65 USD/m3 and 2.3 USD/m3 for EC + F and EC + PF, respectively. © 2018 Elsevier B.V.Ítem Optimization and toxicity assessment of a combined electrocoagulation, H2O2/Fe2+/UV and activated carbon adsorption for textile wastewater treatment(Elsevier, 2019-02-15) GilPavas, E; Dobrosz-Gomez, I; Gomez-Garcia, MA; Universidad EAFIT. Departamento de Ingeniería de Procesos; Desarrollo y Diseño de ProcesosIn this study, the potential application of sequential Electrocoagulation + Fenton (F) or Photo-Fenton (PF) + Active carbon adsorption (EC + F/PF + AC) processes were analyzed as alternatives for the treatment of an industrial textile wastewater resulting from an industrial facility located in Medellín (Colombia). In order to maximize the organic matter degradation, each step of the treatment was optimized using the Response Surface Methodology. At first, the optimal performance of EC was achieved with Fe electrodes operating at pH = 7, jEC = 10 mA/cm2 and 60 rpm, during 10 min of electrolysis. At these conditions, EC let to remove 94% of the dye's color, 56% of the COD and 54% of the TOC. Next, sequentially applied Fenton or photo-Fenton process (i.e., EC + F/PF), operating at the optimized conditions (pH = 4.3, [Fe2+] = 1.1 mM, [H2O2] = 9.7 mM, stirring velocity = 100 rpm and reaction time = 60 min.), improved the quality of the treated effluent. The EC + F let to achieve total color reduction, as well as COD and TOC removals of 72 and 75%, respectively. The EC + PF reached 100% of color, 76% of COD and 78% of TOC reductions. The EC + F/PF processes were more efficient than EC in elimination of low molecular weight (<5 kDa) compounds from wastewater. Moreover, the BOD5/COD ratio increased from 0.21 to 0.42 and from 0.21 to 0.46 using EC + F and EC + PF processes, respectively. However, EC + F/PF were not fully effective for the removal of acute toxicity to Artemia salina: 20% and 60% of reduction in toxicity using EC + F and EC + PF, respectively, comparing to very toxic (100%) raw textile wastewater. Thus, activated carbon adsorption was applied as an additional step to complete the treatment. After AC adsorption, the acute toxicity decreased to 10% and 0% using EC + F and EC + PF, respectively. The total operational costs, including chemical reagents, electrodes, energy consumption and sludge disposal, were of 1.65 USD/m3 and 2.3 USD/m3 for EC + F and EC + PF, respectively. © 2018 Elsevier B.V.Ítem Remoción de colorantes de aguas residuales resultantes del tinturado de flores(Universidad EAFIT, 2017) Giraldo Raigoza, Manuela; Medina Arroyave, José DavidÍtem Thermodynamic analysis of CO2 removal process by adsorption on NaX(Universidad EAFIT, 2021) Ortega Arcila, Laura; Serquera Mesa, Sebastián; Builes Toro, SantiagoThe continuous increase of carbon dioxide concentration in the atmosphere is the main contributor to climate change. Thus, it is imperative to develop strategies that help to control manmade emissions of this gas. Carbon dioxide capture is an intensive research area that aims to decrease the energy requirements for the separation and storage of CO2. Even though absorption using an aqueous solvent is a well-established and is the most widely implemented capture technology, it requires high energy for the regeneration of the solvent due to the need to increase the temperature of the aqueous solvent, decreasing the overall efficiency of the process. Adsorption using porous solids has been presented as an alternative process to capture CO2 while decreasing the energy requirements. In the present work, a thermodynamic analysis of the CO2 removal process by adsorption using literature reported data is performed, in order to devise a framework to evaluate and compare two adsorbents under realistic process conditions. Zeolites NaX and Beta were used as case studies to evaluate the proposed model. The results show that, although bed composition profiles have similar trends for both adsorbents, there is a significant difference in the regeneration temperature of these adsorbents, since for zeolite NaX the regeneration temperature is reached around 360K when CO2 is almost pure, whereas for Beta this value is reached around 390K. Thus, NaX has a lower energy requirement than Beta for stablished process conditions. The energy penalty is 91.08 MW per molCO2 recovered for NaX and 104.28 MW per molCO2 recovered for Beta, which is consistent with the calculation of the specific thermal energy and the working capacity.