RETRACTED: Co-fermentation of magnesium oxide-treated corn stover and corn stover liquor for cellulosic ethanol production and techno-economic analysis

Abstract

MgO is an effective catalyst to reduce the recalcitrant structure of corn stover and reduce sugar degradation during pretreatment. To evaluate the economic feasibility of MgO pretreatment, techno-economic analysis was performed at a commercial scale of 700,000 MT stover per year based on the collected experimental data. Compared to LHW pretreatment, MgO pretreatment reduced total capital investment due to elimination of solids washing and increased ethanol yield by 78.4 L/MT stover due to higher xylose yield (53.4 vs 10.9%), thus resulted in a lower minimum ethanol selling price (MESP) of $0.72/liter. Although washing of MgO-pretreated solids improved glucose (73.0 vs 69.5%) and xylose (66.0 vs 53.4%) yields, MESP did not decrease but increase by $0.08/liter due to the high capital cost of solid-liquid separation unit. Tween 80 also improved glucose (73.1 vs 69.5%) and xylose (62.6 vs 53.5%) yields. However, its high cost limited its economic feasibility in ethanol production.