FRACTIONATION OF SPRUCE TRICHLOROACETIC LIGNIN
M. Likon1, A. Perdih2
1 Polisinteza d.o.o., Dekani 3a, 6271 Dekani, Slovenia
2Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerèeva 1000 Ljubljana, Slovenia
Fractionation of spruce lignin isolated by trichloroacetic acid at 90°C with organic solvents shows inhomogeneity of lignin. Diethylether extracts the biggest part of isolated lignin, whereas dichloromethane extracts part of lignin with greater Mw, Mn and Mz. Extracted fractions and insoluble residues were examined by FTIR spectroscopy showing that polar solvents extract fractions with more hydroxyl groups and lower trichloroacetylation degree than less polar organic solvents.