87 Acta Chim. Slov. 1999, 46(1), pp. 87-97 FRACTIONATION OF SPRUCE TRICHLOROACETIC LIGNIN † M. Likon 1 , A. Perdih 2 1 Polisinteza d.o.o., Dekani 3a, 6271 Dekani, Slovenia 2 Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000 Ljubljana, Slovenia (Received 10.3.1998) ABSTRACT Fractionation of spruce lignin isolated b 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. Keywords: extraction, organic solvents, lignin, trichloroacetic acid, GPC, FTI INTRODUCTION In the early 1940, Schütz succeeded in delignifying spruce wood with 80% chloroacetic acid at 113°C, but he concluded tha delignification of wood with 100% chloroacetic acid is not possible due to carbonisation of wood [1]. Our investigations show that the delignification of lignocellulose with haloacetic acids has some promises to become an organosolv pulping process [2,3]. After delignification of spruce wood with trichloroacetic (TCA) acid at 90°C cellulosic fibers with kappa number 11.5 and soluble † Dedicated to memory of Professor Anton Šebenik