Biorefinery of Lignocellulosic Biomass from an Elm Clone: Production of Fermentable Sugars and Lignin-Derived Biochar for Energy and Environmental Applications

Valorization of lignocellulosic feedstock from a Dutch elm disease tolerant Ulmus minor clone was studied as a new biomass resource. Herein, fermentable sugars and activated carbons from the side-stream lignins were produced. For the sugar extraction organosolv and acid hydrolysis pretreatments prior to enzymatic hydrolysis were compared for the first time for this clone prior to enzymatic hydrolysis; organosolv was more efficient for delignification (49 %), while acid hydrolysis was more efficient at eliminating hemicelluloses (95 %). A high final glucose concentration of 22-23.5 g L-1 was obtained after enzymatic hydrolysis suggesting that this clone can be considered a potential source for glucose-based biofuel production. The side-stream lignins were converted to microporous biochars of high surface area (1220 m(2) g(-1)) and micropore volume (0.42 cm(3) g(-1)). These biochars exhibited excellent properties as electrodes in supercapacitors with a specific capacitance of 118 F g(-1) and a high energy density of 14 Wh kg(-1) at 7000 W kg(-1), while they were also efficient adsorbents in water remediation of model contaminants.