| abstract |
A process for purifying an aqueous solution containing sugars, formed as main or side- streams during physical, physico-chemical or chemical pre-treatmet of lignocellulosic material, wherein the process comprises the steps of mixing a precipitating agent such as barium hydroxide or calcium hydroxide to form a precipitate and separating some of the precipitate from the aqueous solution in order to remove toxic hydrolysis by-products such as furfural, HMF, furans, phenols, acetic acid, formic acid, etc. |