Organosolv extraction of softwood combined with lignin-to-liquid-solvolysis as a semi-continuous percolation reactor. (April 2017)

• Record Type: Journal Article
• Authors: Løhre, Camilla; Kleinert, Mike; Barth, Tanja
• Is Part Of: Biomass and bioenergy. Volume 99(2017:Apr.)
• Page Start: 147
• Page End: 155
• Publication Date: 2017-04
• Subjects: Biomass pretreatment -- Organosolv -- Continuous process -- Thermochemical conversion -- Lignin-to-liquid -- Phenols; Biomass energy -- Periodicals; Biomass -- Periodicals; Energy-Generating Resources -- Periodicals; Bioénergie -- Périodiques; 333.9539
• DOI: 10.1016/j.biombioe.2017.02.014
• Languages: English
• ISSNs: 0961-9534

Abstract

Abstract: As part of a concept for a continuous biorefining process, a fractionation procedure for lignocellulosic biomass based on flow-through organosolv lignin solubilisation has been developed and tested. Lignin is removed from the biomass in a continuous flow-through system, producing a dissolved lignin fraction and a residual fibre fraction rich in cellulose. A solvent system comprising ethanol, water and sulfuric or formic acid as catalyst is tested over a 413–468 K temperature range. Process conditions that are suitable for fractionation of softwood from Norway spruce are determined using an experimental design. The best conditions give yields up to 86% of the initially determined lignin mass, leaving a clean fibre residue that corresponds to 67% of the initial cellulose mass. The produced lignin fraction can be converted by formic acid assisted solvolysis to a liquid comprising mostly methoxy-phenols at nearly 90% mass yield. The results show that the continuous flow fractionation of lignocellulosic biomass is a promising route for biorefinery processing. Highlights: Semi-continuous organosolv fractionation of biomass providing lignin yields of ≤86% based on lignin mass in feedstock. Optimal fractionation and lignin recovery with solvent ratio 63:37 EtOH:H2 O (mass ratio) and [6.00 mol m − 3 ] H2 SO4, at 448 K. Formic acid assisted solvolytic thermochemical conversion of lignin to bio-oil (LtL) providing conversion yields of ∼90%.