Zusammenfassung
Transition of cellulose crystalline structure in biodegradable mixtures of renewably-sourced levulinate alkyl ammonium ionic liquids, γ-valerolactone and water.
N2 - In this work, we report that combination of levulinate as a renewably sourced anion with short chain alkyl ammonium as a cation yields room temp. ionic liqs. that are capable of dissolving up to 10 wt% of microcryst. cellulose. ...
Zusammenfassung
Transition of cellulose crystalline structure in biodegradable mixtures of renewably-sourced levulinate alkyl ammonium ionic liquids, γ-valerolactone and water.
N2 - In this work, we report that combination of levulinate as a renewably sourced anion with short chain alkyl ammonium as a cation yields room temp. ionic liqs. that are capable of dissolving up to 10 wt% of microcryst. cellulose. This dissoln. results in a change of the cellulose cryst. structure from cellulose I to cellulose II, a pre-requisite step known to significantly improve the accessibility of cellulose to enzymes. As compared to previous methodologies, such ILs tolerate the presence of up to 18 wt% of water. Hence tech. grade ILs can be used, thus avoiding the energy-consuming drying process generally required with traditional ILs before dissoln. expts. In addn., such ILs can be mixed with 20 wt% of γ-valerolactone, a renewably-sourced co-solvent, resulting in an improvement of the cellulose dissoln. up to 20 wt% while concomitantly increasing the sustainability of these media. Finally, prepd. ILs were proved to be biodegradable according to the OCDE 301F directive, thus opening a promising route for the pre-treatment of cellulose with a higher eco-efficiency.