Reversible and non-reactive cellulose separations from ionic liquid mixtures with compressed carbon dioxide

Abstract

A novel physical (non-reactive) separation of cellulose from an ionic liquid (IL)/cosolvent mixture by compressed carbon dioxide is presented. The precipitation is completely reversible and rapid within small changes of pressure i.e. liquid phase CO₂ composition. High pressure phase equilibrium, high pressure NMR, and solid state NMR have been utilized to understand the separation phenomena.