Uso do modelo UNIFAC-LI na seleção de líquidos iônicos para captura do CO2
Data
2022-12-07
Autores
Silva, Amanda de Araújo 
Orientadores
Silva, Luciana Yumi Akisawa
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
De modo geral, as mudanças climáticas e sua relação com atividades humanas têm sido assuntos repercutidos nos últimos anos. Um dos gases de efeito estufa que contribuem para o aquecimento global é o dióxido de carbono (CO2), que é gerado em grandes volumes pela queima de combustíveis fósseis na geração de energia e em atividades industriais. Por isso, para conter a emissão de CO2, sua remoção do gás de combustão por meio de tratamentos é muito importante, o que pode ser feito mediante processos de absorção, utilizando um solvente apropriado. Os líquidos iônicos (LIs) são solventes físico-químicos e sua aplicação em processos da engenharia tem crescido nos últimos anos, por conta de suas propriedades físico-químicas, como sua baixa volatilidade, o que o diferencia de solventes orgânicos voláteis, que são comumente utilizados nos processos de captura de CO2, e que poluem o ar por perda fugitiva. No presente trabalho, foi utilizado o modelo termodinâmico de energia livre de Gibbs em excesso UNIFAC-LI estendido a fim de estimar a solubilidade do CO2 em 19 líquidos iônicos, e os resultados obtidos foram comparados com valores experimentais da literatura, encontrando um desvio relativo médio de 10,28%, certificando que o modelo representou apropriadamente a solubilidade examinada. Com base nos valores das solubilidades calculadas com o UNIFAC-LI a 298,15 K e 1 bar, dentre os LIs estudados, os melhores líquidos iônicos que podem ser empregados no processo de absorção do CO2 seriam os [EMIM][eFAP], [BMIM][eFAP], [BMPYR][Tf2N] e [HMIM][eFAP], com solubilidades encontradas de 46,8, 46,1, 45,4 e 45,4.10-3, respectivamente.
In general, climate change and its relationship with human activities have been matters of repercussion in recent years. One of the greenhouse gases that contribute to global warming is carbon dioxide (CO2), which is generated in large volumes by burning fossil fuels in energy generation and industrial activities. Therefore, in order to contain the emission of CO2, its removal from the flue gas through treatments is very important, which can be done by absorption processes, using an appropriate solvent. Ionic liquids (ILs) are physicalchemical solvents and their application in engineering processes has grown in recent years, due to their physical chemistry properties, such as their low volatility, which differentiates them from volatile organic solventes, that are commonly used in CO2 capture processes, which pollute the air by fugitive loss. In the present work, the excess Gibbs free energy thermodynamic model extended UNIFACIL was used in order to estimate the solubility of CO2 in 19 ionic liquids, and the results obtained were compared with experimental values in the literature, finding a mean relative deviation of 10.28%, certifying that the model adequately represented the solubility examined. Based on the solubility values calculated with UNIFACIL at 298.15 K and 1 bar, among the studied ILs, the best ionic liquids that can be used in the CO2 absorption process would be [EMIM][eFAP], [BMIM][eFAP], [BMPYR][Tf2N] and [HMIM][eFAP], with found solubilities of 46.8, 46.1, 45.4 and 45.4x103, respectively.
In general, climate change and its relationship with human activities have been matters of repercussion in recent years. One of the greenhouse gases that contribute to global warming is carbon dioxide (CO2), which is generated in large volumes by burning fossil fuels in energy generation and industrial activities. Therefore, in order to contain the emission of CO2, its removal from the flue gas through treatments is very important, which can be done by absorption processes, using an appropriate solvent. Ionic liquids (ILs) are physicalchemical solvents and their application in engineering processes has grown in recent years, due to their physical chemistry properties, such as their low volatility, which differentiates them from volatile organic solventes, that are commonly used in CO2 capture processes, which pollute the air by fugitive loss. In the present work, the excess Gibbs free energy thermodynamic model extended UNIFACIL was used in order to estimate the solubility of CO2 in 19 ionic liquids, and the results obtained were compared with experimental values in the literature, finding a mean relative deviation of 10.28%, certifying that the model adequately represented the solubility examined. Based on the solubility values calculated with UNIFACIL at 298.15 K and 1 bar, among the studied ILs, the best ionic liquids that can be used in the CO2 absorption process would be [EMIM][eFAP], [BMIM][eFAP], [BMPYR][Tf2N] and [HMIM][eFAP], with found solubilities of 46.8, 46.1, 45.4 and 45.4x103, respectively.