Instant catapult steam explosion: An efficient preprocessing step for the robust and cost-effective chemical pretreatment of lignocellulosic biomass

The biorefinery based on lignocellulosic biomass requires an efficient preprocessing step to address problems regarding with the high cost of biomass transportation and the low cost-effectiveness of subsequent chemical pretreatment. In this study, the instant catapult steam explosion (ICSE) was investigated as an alternative preprocessing method to treat corn stalk feedstocks, and compared with conventional milling preprocessing. Besides reducing the particle size, ICSE can modify the microstructure and improve enzymatic degradability of the corn stalks as well. These preprocessed feedstocks were further pretreated by moderate chemical pretreatment methods, including dilute acid, dilute alkali, acid and alkali, organosolv, and ionic liquid. The ICSE-treated feedstocks showed 3-fold to 7-fold increase in enzymatic saccharification when compared with milled and untreated feedstocks. Meanwhile, its energy consumption only accounted for 5%–20% of the milling process, thereby resulting in an 80%–85% of energy savings. Therefore, the ICSE-based preprocessing can potentially be integrated with the supply chain of lignocellulosic biomass and enhance the economic efficiency of biorefinery.