(537h) Effect of Polymer Molecular Weight on CO2 Sorption Capacity in Supported Ionic Liquid Membranes
AIChE Annual Meeting
2023
2023 AIChE Annual Meeting
Separations Division
CO2 Capture By Adsorption I
Wednesday, November 8, 2023 - 2:01pm to 2:14pm
With today's energy demands, our dependence on fossil fuels has grown many folds. This leads to
devastating consequences for our environment and ecosystem, resulting in global warming. To address the
generated carbon footprint, carbon capture techniques such as Amine absorption are used to mitigate the
impacts of carbon on the environment. This technology has limitations in terms of operational and
environmental efficiency, toxicity, and operational costs. To overcome these limitations, several
researchers have focused on finding alternative methods, and Ionic Liquids [IL] are among the promising
candidates. As green solvents with low vapor pressure, high thermal stability, tunable structure, low
flammability, and high affinity for CO2, ILs are a great solution to replace conventional carbon capture
technologies. [1] Several recent studies have demonstrated enhanced CO2 solubility for confined ionic
liquids (ILs) within polymeric domains, suggesting a potential for stabilizing ILs within macromolecular
domains and taking advantage of their non-ideal properties. With the potential for ILs to be incorporated
into polymeric domains, understanding the underlying phenomena that govern their non-ideal properties is
a critical task. In this study, the effect of the molecular weight (MW) of polymer on the CO2 adsorption
capacity of supported ionic liquid membranes (SILM) was investigated. Quasi-solid-state films were cast
from mixtures containing 1 Ethyl 3 methylimidazolium bis(trifluoromethylsulfonyl) imide and
Polyvinylidene Fluoride (PVDF) with different Molecular Weight (MW) of 180K and 534K, and the
solubilities of CO2 in these films were measured using gravimetry method. The adsorption isotherms were
obtained at four different temperatures. Our result indicates that the MW of PVDF has a significant impact
on the CO2 solubility in SILMs, highlighting the importance of the intermolecular interaction and swelling
properties of polymer on CO2 sorption within the mixture. According to our findings, the 1:1 IL-polymer
mixture prepared with 180K polymer presents the greatest promise for fabricating SILMs, absorbing 4.3
mol of CO2 per kg of IL. This value is three times higher than the CO2 sorption capacity of IL measured
under the same conditions.
devastating consequences for our environment and ecosystem, resulting in global warming. To address the
generated carbon footprint, carbon capture techniques such as Amine absorption are used to mitigate the
impacts of carbon on the environment. This technology has limitations in terms of operational and
environmental efficiency, toxicity, and operational costs. To overcome these limitations, several
researchers have focused on finding alternative methods, and Ionic Liquids [IL] are among the promising
candidates. As green solvents with low vapor pressure, high thermal stability, tunable structure, low
flammability, and high affinity for CO2, ILs are a great solution to replace conventional carbon capture
technologies. [1] Several recent studies have demonstrated enhanced CO2 solubility for confined ionic
liquids (ILs) within polymeric domains, suggesting a potential for stabilizing ILs within macromolecular
domains and taking advantage of their non-ideal properties. With the potential for ILs to be incorporated
into polymeric domains, understanding the underlying phenomena that govern their non-ideal properties is
a critical task. In this study, the effect of the molecular weight (MW) of polymer on the CO2 adsorption
capacity of supported ionic liquid membranes (SILM) was investigated. Quasi-solid-state films were cast
from mixtures containing 1 Ethyl 3 methylimidazolium bis(trifluoromethylsulfonyl) imide and
Polyvinylidene Fluoride (PVDF) with different Molecular Weight (MW) of 180K and 534K, and the
solubilities of CO2 in these films were measured using gravimetry method. The adsorption isotherms were
obtained at four different temperatures. Our result indicates that the MW of PVDF has a significant impact
on the CO2 solubility in SILMs, highlighting the importance of the intermolecular interaction and swelling
properties of polymer on CO2 sorption within the mixture. According to our findings, the 1:1 IL-polymer
mixture prepared with 180K polymer presents the greatest promise for fabricating SILMs, absorbing 4.3
mol of CO2 per kg of IL. This value is three times higher than the CO2 sorption capacity of IL measured
under the same conditions.
[1] Progress in the Separation Processes for Rare Earth Resources. Zhang Z, Jia Q, Liao W. Handbook on the
Physics and Chemistry of Rare Earth (2015).