Enhanced digestibility and fermentability of sugarcane bagasse in biofuel production by surfactant-assisted dilute acid pretreatment

•A combined process was developed in order to gain high-energy yields.•Three typical surfactants were evaluated on various pretreatment technologies.•The maximum glucose yield of 86.14 % was achieved by PEG 6000 assisted 2 % H2SO4 pretreatment.•The digestibility and fermentability significantly increased by adding surfactants.