Table 2.

Composition of lignin obtained with each organosolv pretreatment. Weight average (M_W), number-average (M_n), and polydispersity index (PDI) of acid-insoluble lignin from birch sawdust were determined after acetobromination.

Code	Cellulose (%)	Hemicellulose (%)	Klason Lignin (%)	Ash (%)	MW (g/mol)	Mn (g/mol)	PDI
B0A5a	0.08	1.85	95.18	0.47	4500	1200	3.75
B0A6a	0.14	2.32	83.86	0.27	8000	1100	7.34
B0A6c	0.50	0.32	86.44	0.42	9700	1400	6.97
B0B5a	0.39	1.56	92.00	0.72	11300	1400	8.21
B0B6a	0.00	2.01	91.90	0.31	13300	1700	8.04
B1A5a	0.14	3.55	77.93	0.12	1800	800	2.28
B1A6a	0.18	7.04	74.27	0.21	4500	1200	3.87
B1B5a	0.10	2.48	83.08	0.11	4600	1200	3.88
B1B6a	0.11	3.25	89.05	0.08	15900	1900	8.53

Representation of the codes: 0—pretreatment at 200 °C; 1—pretreatment at 180 °C; A—pretreatment time of 15 min; B—pretreatment of 30 min; 5—50% v/v ethanol content; 6—60% v/v ethanol content; a—no catalyst added; c—1% w/w_biomass H₂SO₄.