Catalytic Decomposition of Cellulose in Cooperative Ionic Liquids

Cellulose, the abundant and cost-ineffective resource, is considered to be a perfect alternative for the alleviation of energy crisis and environmental pollution. However, most processes for the treatment of cellulose are rigor currently as it is insoluble in water and conventional organic solvents due to its strong intra and inter-molecular hydrogen bonds, where the phase problem hampers its utilization widely. Here, we built a novel and efficient cooperative ionic liquid pairs system for the low temperature catalytic conversion of cellulose, which was constructed through the combination of an acidic ionic liquid catalyst and a cellulose soluble ionic liquid solvent. The catalytic decomposition behavior of microcrystal cellulose in this vigorous catalytic system was studied intensively by thermogravimetry (TG). Results show that the decomposition temperature of cellulose decreases greatly in all cooperative ionic liquid pairs, cellulose dissolved in ionic liquid solvents can be in situ catalytic decomposed by acidic ionic liquids. Furthermore, the decomposition temperature is dependent on the acidic strength of the ionic liquid catalysts, stronger acidity results in a lower decomposition temperature of the cellulose. Moreover, we found that cellulose can be decomposed at lower temperature when the ionic liquid with higher solubility of cellulose is used.