Abstract: The subject disclosure relates to a method for producing a fermentation product from biomass that has been pre-treated in a pre-treatment system and separated into a liquid component and a first solids component. The method comprises: (a) treating the liquid component in a filtration system comprising at least one nano-filter to produce a treated liquid component, and to remove an acid from the liquid component; (b) supplying the treated liquid component, a fermenting organism, and agents to a fermentation system; (c) recovering the fermentation product from the fermentation system; and (d) supplying the acid for re-use in the pre-treatment system. In many embodiments, the biomass comprises lignocellulosic material and the liquid component comprises pentose (e.g., xylose).

Abstract: Systems and methods for increasing fermentation efficiency of a lignocellulosic hydrolysate are disclosed. The system comprises a filter configurable to remove matter having a particle size of larger than about 25 to 100 microns from the liquid component, and at least one nanofilter configurable to remove acids from the liquid component. An apparatus is used to adjust the pH of the nanofiltered liquid component using a calcium hydroxide composition to a pH of about 5.5 to 6.0. The calcium hydroxide composition includes calcium hydroxide alone or in combination with either ammonium hydroxide and/or potassium hydroxide. The biomass comprises lignocellulosic material including at least one of corncob, corn plant husk, corn plant leaves, and corn plant stalks.