Ionic liquids from renewable biomaterials: synthesis, characterization and application in the pretreatment of biomass

Abstract

A series of room temperature ionic liquids (ILs), in which cholinium acts as the cation and amino acids as the anions, were prepared via a simple and green chemical route, and characterized. Most of the ILs dissolved lignin efficiently and selectively (with solubilities of 140–220 mg of lignin per g of IL). The solubility of xylan in these ILs (which ranged from <1 to 85 mg g⁻¹) depended on the nature of the anion, while cellulose was scarcely soluble (<5 mg g⁻¹). In addition, enzymatic hydrolysis of microcrystalline cellulose and rice straw was enhanced significantly after pretreatment using the IL [Ch][Gly].