Solvent Impregnated Polymers for Carbon Capture

Microencapsulation of liquid solvents is a promising approach to utilizing viscous, corrosive, or kinetically limited solvents for large-scale gas separations in a practical manner. A major drawback of the technology is the difficulty of manufacturing capsules on an industrial scale. In this article, an alternative means of immobilizing liquid solvents inside high-surface-area polymers is proposed. A gel material containing ∼50 wt % solvent embedded inside a continuous polymer matrix is formed by a scalable one-pot method. The material may be shaped into thin films or particles with surface areas comparable to microcapsules, and gels containing concentrated K2CO3 solutions were stable through multiple cycles of gas absorption/regeneration and hydration/dehydration. Mass transfer measurements were in good agreement with a theoretical model, which predicted that, for concentrated solvents inside gels of appropriate thickness, the high permeability of the polymer can increase the gas flux into the material relative to a neat solvent.