title: Advanced process for precipitation of lignin from ethanol organosolv spent liquors.
abstract: An advanced process for lignin precipitation from organosolv spent liquors based on ethanol evaporation was developed. The process avoids lignin incrustations in the reactor, enhances filterability of the precipitated lignin particles and significantly reduces the liquor mass in downstream processes. Initially, lignin solubility and softening properties were understood, quantified and exploited to design an improved precipitation process. Lignin incrustations were avoided by targeted precipitation of solid lignin at specific conditions (e.g. 100 mbar evaporation pressure, 43°C and 10%wt. of ethanol in lignin dispersion) in fed-batch operation at lab and pilot scale. As result of evaporation the mass of spent liquor was reduced by about 50%wt., thus avoiding large process streams. By controlled droplet coalescence the mean lignin particle size increased from below 10 μm to sizes larger than 10 μm improving the significantly filterability.
authors.affiliation: Max-Planck-Institute for Dynamics of Complex Technical Systems DCTS, Magdeburg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Schulze
authors.affiliation: Max-Planck-Institute for Dynamics of Complex Technical Systems DCTS, Magdeburg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Seidel-Morgenstern
authors.affiliation: Max-Planck-Institute for Dynamics of Complex Technical Systems DCTS, Magdeburg, Germany.
authors.forename: Heike
authors.initials: H
authors.lastname: Lorenz
authors.affiliation: Fraunhofer Center for Chemical-Biotechnological Processes CBP, Leuna, Germany.
authors.forename: Moritz
authors.initials: M
authors.lastname: Leschinsky
authors.affiliation: Fraunhofer Center for Chemical-Biotechnological Processes CBP, Leuna, Germany.
authors.forename: Gerd
authors.initials: G
authors.lastname: Unkelbach
mesh_terms: D011232:Chemical Precipitation; D000431:Ethanol / Q000737:chemistry*; D007220:Industrial Waste; D008031:Lignin / Q000737:chemistry*; D012995:Solubility
chemical_list: D007220:Industrial Waste; D000431:Ethanol; D008031:Lignin
keywords: Lignin; Lignocellulose biorefinery; Organosolv; Precipitation