Absorption of CO2 in lyotropic liquid crystals

Abstract

Vapor–liquid equilibria data of three poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)/water liquid crystals (LCs) with CO2 has been obtained up to 6 bar. The investigated LCs consist of 60% (EO)3(PO)50(EO)3 (Pluronic L81), 70% (EO)8(PO)47(EO)8 (Pluronic L92), and 70% L92-NH2. The maximum CO2 loading of the LCs was 5–13 g CO2/kg sample. Pure L81 and L92 displayed higher absorption of CO2 than the LCs. Rheology measurements revealed that the increasing viscosity of the samples decreases the CO2 loading. Water diffusion in the LCs was qualitatively investigated by nuclear magnetic resonance, confirming that free water and tightly bound water are present in the LCs.