Aqueous acidified ionic liquid pretreatment for bioethanol production and concentration of produced ethanol by pervaporation

[Display omitted] •Adding water to IL reduces the viscosity and facilitates high biomass loading.•Acidified [Bmim]Cl pretreatment efficiently removed hemicellulose.•Cellulose conversion of pretreated biomass was 93.56–99.81%.•Fermentation produced 21.86–29.56g/L ethanol and ethanol yield was 0.49–0.51g/g.•Produced bioethanol was concentrated up to 79.8% by consecutive pervaporation. Acidified [Bmim]Cl solution showed a great efficacy for the pretreatment of softwood, hardwood, rice straw, and sugarcane bagasse. The pretreatment resulted in 29 and 20-fold increase in cellulose digestibility of hardwood and softwood, respectively, and most cellulose in rice straw and sugarcane bagasse was converted into glucose. Fermentation of biomass hydrolysates produced 21.86–29.56g/L ethanol, thereby achieving ethanol yields of 0.49–0.51g/g. Ethanol was concentrated up to 79.8% from a fermentation broth containing 2.4% ethanol using four consecutive pervaporations. This work demonstrates the viability of biofuel production from diverse feedstocks and the feasibility of ethanol recovery using pervaporative separation.