Fractionation of sulphite spent liquor for biochemical processing using ion exchange resins

► The composition of hardwood sulphite spent liquor (HSSL) was assessed. ► HSSL was fractionated employing fixed-bed cationic and anionic resins in series. ► HSSL fractionation allowed separation/retention of inhibitors from sugars. ► Fractionated sugars from HSSL is a suitable substrate for bioprocessing into biofuels.