Novel biorefining method for succinic acid processed from sugarcane bagasse

Sugarcane bagasse (SCB) was pretreated with hot water (HLW), ethanol (ETH), and sodium hydroxide (SH). The obtained residuals were hydrolyzed and applied as carbon sources for succinic acid (SA) fermentation, the residue digestibility and SA conversion rate of alkali-pretreated residual were superior to others. Considering the characteristics of alkali pretreatment, enzymatic hydrolysis and succinic acid fermentation, a novel in-situ semi-simultaneous saccharification and co-fermentation (SSSCF) procedure for SA production from SCB was developed. The yield, productivity, and conversion rates of SA from SCB raw material (DRM) processed by SSSCF were 41 g/L, 300 mg/L/h, and 320 mg/g dry, respectively. For every kilogram of SA production, the developed coupling method reduced the SH and water usages, energy consumption, and effluent emission by 0.14 kg, 233.5 L 14,000 kJ and 7 L, respectively, and enhanced the SA productivity by 1.7 times compared with the non-coupling procedure.