Fuel ethanol production from corncob using dilute acid pretreatment and separated saccharification and fermentation by fed-batch strategy

The aim of this study was to achieve the optimum process parameters for fuel ethanol production from corncob. After the optimization of orthogonal experiment, the process configuration including dilute acid pretreatment and separated saccharification and fermentation (SHF) by fed-batch strategy was obtained. The optimum conditions of pretreatment were that corncob was treated with 1.1% sulphuric acid and solid-to-liquid ratio=l:8 at 120°C for 3hours. After delignification with alkaline, water insoluble solid of 180g·L^-1 were hydrolyzed with cellulase loading of FPA (IU·mL^-1): CBA (IU·mL^-1)=20:7 to per gram substrate at 48 °C and initial pH5.0. The maximum ethanol concentration from enzymatic hydrolysates fermented by Zymomonas mobilis at 35°C for 48hours reached 57.8g·L^-1.