Pretreatment with a combination of steam explosion and NaOH increases butanol production of enzymatically hydrolyzed corn stover

As an essential lignocellulosic source, corn stover (CS) arouses an extensive interest in transforming into bio-butanol and high-value-added products. Optimization experiments of medium and kinetic fermentation experiments of Clostridium acetobutylicum CICC 8008 were conducted. The CS was pretreated by a combination of steam explosion and NaOH, followed by saccharification by cellulase. The saccharification liquor contained 65.91 g/L of total reducing sugar. The optimum fermentation medium was 1,000 mL saccharification liquor supplemented with 4.89 g/L yeast extract, 6.9 g/L CaCO3, and 10.56 mg/L biotin. When the optimum medium was used in the butanol fermentation process, the maximum acetone-butanol-ethanol (ABE) content was 41.78 g/L, and the contents of acetone, butanol, and ethanol were 9.73, 23.82, and 8.23 g/L, respectively. The maximum specific growth rate was 0.066 h−1, the coefficient of growth was 2.29 g/(gL), and no substrate and production inhibition were found. ABE was the growth-associated metabolite. Collectively, our current findings provided valuable insights into the efficient application of lignocellulose biomass into the biorefinery of butanol.