Examinando por Autor "Builes, Santiago"

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    Proceso de ASC - INSTRUMENTACION SISTEMA PARA LA CAPTURA DE CO2 A ESCALA DE LABORATORIO
    (Universidad EAFIT, 2021) Ochoa Botero, Emilio; Escobar Gallego, David; Dietl, Marcel; Builes, Santiago; Universidad EAFIT
    The increasing use of fossil fuels for energy generation and the high emission of greenhouse gases associated with these processes have made it necessary to develop technologies that can mitigate their impact. The chemical absorption process of CO2 using aqueous amines has been implemented in the industry for several decades and is considered a viable strategy for medium-term CO2 emissions mitigation. Pumping highly viscous fluids such as amines requires large amounts of energy, and they are commonly mixed with water to improve their fluidity. This mixture negatively impacts reaction rates, resulting in the need for larger equipment to capture the same amounts of CO2. Additionally, the regeneration process of aqueous amines requires the supply of large amounts of energy to increase their temperature and release the CO2. These kinetic and energetic characteristics of the process are the main obstacles to the widespread implementation and extensive use of this technology in the industry. This work continues the construction process of a plant for chemical absorption using aqueous amines. It builds upon the construction of a gas capture plant that took place in 2018, aiming to operate in a steady state and monitor the performance of different types of amines, amine mixtures, and operational conditions of the system in order to find alternatives that can reduce the energy cost of the process.
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    Proceso de ASC - INTEGRACION DE PLANTA A ESCALA DE LABORATORIO PARA LA CAPTURA DE CO2 POR ABSORCION-DESORCION CON AMINAS ACUOSAS
    (Universidad EAFIT, 2019) Román Restrepo, Valeria; Restrepo Lopera, Juan Pablo; Betancur Osorio, Camilo; Sepulveda García, Yessenia; Arboleda Otero, Mariana; Builes, Santiago; Universidad EAFIT
    The increasing use of fossil fuels for energy generation and the high emission of greenhouse gases associated with these processes have made it necessary to develop technologies that can mitigate their impact. The chemical absorption process of CO2 using aqueous amines has been implemented in the industry for several decades and is considered a viable strategy for medium-term CO2 emissions mitigation. Pumping highly viscous fluids such as amines requires large amounts of energy, and they are commonly mixed with water to improve their fluidity. This mixture negatively impacts reaction rates, resulting in the need for larger equipment to capture the same amounts of CO2. Additionally, the regeneration process of aqueous amines requires the supply of large amounts of energy to increase their temperature and release the CO2. These kinetic and energetic characteristics of the process are the main obstacles to the widespread implementation and extensive use of this technology in the industry. This work continues the construction process of a plant for chemical absorption using aqueous amines. It builds upon the construction of a gas capture plant that took place in 2018, aiming to operate in a steady state and monitor the performance of different types of amines, amine mixtures, and operational conditions of the system in order to find alternatives that can reduce the energy cost of the process.
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    Ítem
    A Semiempirical Method to Detect and Correct DFT-Based Gas-Phase Errors and Its Application in Electrocatalysis
    (AMER CHEMICAL SOC, 2020-06-19) Granda-Marulanda, Laura P.; Rendon-Calle, Alejandra; Builes, Santiago; Illas, Francesc; Koper, Marc T. M.; Calle-Vallejo, Federico; Universidad EAFIT. Departamento de Ingeniería de Procesos; Desarrollo y Diseño de Procesos
    Computational models of adsorption at metal surfaces are often based on DFT and make use of the generalized gradient approximation. This likely implies the presence of sizable errors in the gas-phase energetics. Here, we take a step closer toward chemical accuracy with a semiempirical method to correct the gas-phase energetics of PBE, PW91, RPBE, and BEEF-vdW exchange-correlation functionals. The proposed two-step method is tested on a data set of 27 gas-phase molecules belonging to the carbon cycle: first, the errors are pinpointed based on formation energies, and second, the respective corrections are sequentially applied to ensure the progressive lowering of the data set's mean and maximum errors. We illustrate the benefits of the method in electrocatalysis by a substantial improvement of the calculated equilibrium and onset potentials for CO2 reduction to CO on Au, Ag, and Cu electrodes. This suggests that fast and systematic gas-phase corrections can be devised to augment the predictive power of computational catalysis models.