Combined organosolv and ultrafiltration lignocellulosic biorefinery process

Non-woody lignocellulosic feedstock (Miscanthus sinensis L.) was fractionated by a biorefinery process to obtain cellulose, different molecular weight lignin fractions and an hemicelluloses enriched liquor following economically and environmentally sustainable criteria. An integrated process composed by ethanol organosolv pre-treatment followed by a membrane ultrafiltration system was used to extract the different fractions. Products physico-chemical characterization (FTIR, GPC, 1H NMR) was done to evaluate their potential possible industrial applications. Obtained experimental data were used to develop a simulation of the process using Aspen Plus software in order to establish mass and energy balances and optimize the process in terms of yield, solvent recovery and energy consumption. Finally, production costs of the obtained ultrafiltrated lignin were estimated resulting in 52 €/tonne of lignin for the studied process conditions.