TY - JOUR

T1 - Thermochemical study of CO2 capture by mesoporous silica gel loaded with the amino acid ionic liquid 1-ethyl-3-methylimidazolium glycinate

AU - Sheshkovas, Andrey Z.

AU - Veselovskaya, Janna V.

AU - Rogov, Vladimir A.

AU - Kozlov, Denis V.

N1 - Funding Information: This work was supported by the Ministry of Science and Higher Education of the Russian Federation within the governmental order for Boreskov Institute of Catalysis (project АААА-А21-121011390006-0 ). Authors thank A.A. Leonova and Dr. E.Yu. Gerasimov for performing N 2 adsorption and SEM/STEM experiments, which were carried out using facilities of the shared research center “National center of investigation of catalysts” at Boreskov Institute of Catalysis. Publisher Copyright: © 2022 Elsevier Inc.

PY - 2022/8

Y1 - 2022/8

N2 - A series of composite CO2 sorbents were obtained by placing an amino acid ionic liquid (AAIL) 1-Ethyl-3-methylimidazolium glycine ([Emim][Gly]) into mesoporous silica gel using an impregnation method. The parameters of the porous structure for the silica support and composite sorbents were determined from nitrogen adsorption-desorption isotherms measured at 77 K. The morphology of the materials was studied using field-emission scanning electron microscopy. It was shown that at lower [Emim][Gly] loadings (<50 wt%), the sorption is fast and the dynamic CO2 sorption capacity of the material is proportional to the mass content of the AAIL. At higher [Emim][Gly] loadings (≥50 wt%), the rate of CO2 sorption by the AAIL decreases due to hindered mass transfer. An increase in CO2 concentration in the gas flow leads to a faster sorption and higher CO2 sorption capacity for the AAIL-containing composite. Meanwhile, the integral enthalpy of sorption decreases with increasing CO2 concentration, which can be explained by the greater contribution of physical adsorption/absorption processes to the total CO2 sorption capacity at higher CO2 concentrations. The most promising composite material (40 wt% [Emim][Gly]/SiO2) was tested in consecutive temperature-swing sorption-desorption cycles. It was demonstrated that lowering the regeneration temperature from 100 to 80 °C leads to a decrease in the dynamic sorption capacity of the material, but ensures its stability in the cyclic sorption-desorption process.

AB - A series of composite CO2 sorbents were obtained by placing an amino acid ionic liquid (AAIL) 1-Ethyl-3-methylimidazolium glycine ([Emim][Gly]) into mesoporous silica gel using an impregnation method. The parameters of the porous structure for the silica support and composite sorbents were determined from nitrogen adsorption-desorption isotherms measured at 77 K. The morphology of the materials was studied using field-emission scanning electron microscopy. It was shown that at lower [Emim][Gly] loadings (<50 wt%), the sorption is fast and the dynamic CO2 sorption capacity of the material is proportional to the mass content of the AAIL. At higher [Emim][Gly] loadings (≥50 wt%), the rate of CO2 sorption by the AAIL decreases due to hindered mass transfer. An increase in CO2 concentration in the gas flow leads to a faster sorption and higher CO2 sorption capacity for the AAIL-containing composite. Meanwhile, the integral enthalpy of sorption decreases with increasing CO2 concentration, which can be explained by the greater contribution of physical adsorption/absorption processes to the total CO2 sorption capacity at higher CO2 concentrations. The most promising composite material (40 wt% [Emim][Gly]/SiO2) was tested in consecutive temperature-swing sorption-desorption cycles. It was demonstrated that lowering the regeneration temperature from 100 to 80 °C leads to a decrease in the dynamic sorption capacity of the material, but ensures its stability in the cyclic sorption-desorption process.

KW - Carbon capture

KW - carbon dioxide

KW - Composite material

KW - Ionic liquid

KW - Silica gel

UR - http://www.scopus.com/inward/record.url?scp=85134731087&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/3d8474dd-c4aa-355c-8c0b-4403b7f2f828/

U2 - 10.1016/j.micromeso.2022.112113

DO - 10.1016/j.micromeso.2022.112113

M3 - Article

AN - SCOPUS:85134731087

VL - 341

JO - Microporous and Mesoporous Materials

JF - Microporous and Mesoporous Materials

SN - 1387-1811

M1 - 112113

ER -