Optimization of processing conditions for the pretreatment of wheat straw using aqueous ionic liquid

► Pretreatment of wheat straw using aqueous ionic liquid 1-ethyl-3-methylimidazolium acetate was investigated. ► Optimization of process employed a central composite design. ► Aqueous ionic liquid pretreatment was successful in removal of lignin and enhancement of cellulose and xylan digestibility. ► The optimum processing condition for fermentable sugars yield was determined to be 158 °C, 3.6 h, and an ionic liquid concentration of 49.5% (w/w). ► The results of this work will be valuable for scaling-up experiments and future commercialization.