Enhanced dissolution of cellulose in CO 2 switchable system by solvent with low Henry's constants as CO 2 absorbent

Organic solvents with low Henry's constants, such as propylene carbonate (PC) and sulfolane, were proposed to be used as CO 2 absorbents to increase CO 2 absorption capacity in the CO 2 switchable solvent, so that the dissolution of cellulose can be effectively enhanced. With the addition of PC, the maximum concentration achieved for the dissolution of paper cellulose can be largely increased from 1.0 to 5.0 wt%, while those for microcrystalline cellulose and corncob cellulose were increased from 5.0 to 10.0 and 7.0 wt%, respectively. Moreover, the chemical and crystalline structure of the regenerated cellulose was not affected by the addition of CO 2 absorbents. This study illustrated a simple and effective way to modify the CO 2 switchable solvent, which would be helpful for the application of the complex solvent system for the enhanced dissolution, derivatization, and processing of cellulose in the future.