Patent ID: 8911979
Filing Date: 2014-12-16
Classification: B01B,B01D,C01C,C01D,C05B,C05C,C05D,C05F,C12P,Y02E

Abstract:
1. A process, comprising the steps of: a) washing or leaching a lignocellulosic feedstock comprising inorganic salts which comprise at least potassium and calcium ions with an aqueous solution for a sufficient time to produce an aqueous leachate stream, wherein the washing or leaching duration and the pH of the aqueous solution are sufficient to extract inorganic ions comprising potassium from the feedstock while substantially retaining calcium ions in the feedstock to produce i) an aqueous leachate stream comprising inorganic salts that are substantially free of calcium and ii) a solid leached or washed feedstock; b) removing the aqueous leachate stream from the leached or washed feedstock; c) pretreating the leached or washed feedstock with acid to produce a pretreated lignocellulosic feedstock comprising at least pentose sugar; d) fermenting the pentose sugar with at least one microbe; e) concentrating said aqueous leachate stream produced in step (a) by evaporation, filtering through a reverse osmosis membrane, or a combination thereof; and f) recovering a concentrated aqueous leachate stream produced in step (e).