Potential of a short rotation coppice poplar as a feedstock for platform chemicals and lignin-based building blocks

In the context of a biorefinery, the potential of the short rotation coppice ""poplar with bark"" as a feedstock for the acid-catalyzed ethanol-water Organosolv process and furthermore for possible applications of the biomass components was investigated aiming at optimal separation of the non-standardized woody biomass. The study was supported and evaluated by an experimental design (Box-Behnken). The statistical analysis showed an increase in lignin yield with rising process intensity with an optimum for precipitated lignin yield of 42%. A change in downstream processing from lignin precipitation by simple dilution of the reaction water to stripping of the ethanol provided a 10% higher lignin yield. Molecular weight distribution of the lignin samples as well as the number of aliphatic OH-groups within the lignin molecules decreased with intensified conditions whereas the phenolic group content increased. The cellulose content in the fibre fraction is hardly influenced by the pulping conditions, lignin and hemicellulose removal lead to a raising cellulose recovery.