Evaluation of supported multi-functionalized amino acid ionic liquid-based sorbents for low temperature CO2 capture

The CO2 capture performance of a novel amino acid ionic liquid (AAIL), 1-aminopropyl-3-methylimidazolium lysine ([APMIM][Lys]), impregnated into a mesoporous silica pore-expanded SBA-15 (PE-SBA-15) and a commercial poly(methyl methacrylate) (PMMA) supports was evaluated. The thermogravimetric analysis (TGA) was conducted to analyze the effect of AAIL impregnation on the thermal stability of the sorbents. X-ray diffraction (XRD) compared the intrinsic structure of PMMA with and without AAIL loading. Additionally, the surface area and pore volume decreased, when the AAIL loading increased, which suggests the effective impregnation of AAIL into the porous surface of the supports. Moreover, kinetics analysis was carried out using a double exponential model. The analysis indicates the CO2 uptake of the sorbents was affected not only by the AAIL loading, but also the AAIL dispersion on the surface of supports. According to the CO(2 )isotherms, the isosteric enthalpy of adsorption was calculated based on the Freundlich model and Clausius-Clapeyron equation. The best sorbent was 50 wt%[APMIM][Lys]-based PMMA, since it had the highest CO2 capacity, a fast adsorption kinetics and an enhanced chemisorption of CO2.

Automated summary

The study evaluated the CO2 capture performance of a novel amino acid ionic liquid impregnated into different supports, finding that AAIL effectively impregnated onto the porous surface of the supports, and that both the AAIL loading and dispersion had an impact on CO2 adsorption.