Lignin Methylation and Acetylation (Crawford and
Pometto, 1988). Lignin (200 mg) was suspended in 5 mL of
diethyl ether and then treated with an excess of diazomethane
for 24 h at room temperature. The treatment was repeated
three times. The mixture was centrifuged, washed with ethyl
ether, and centrifuged again. The residue was dried under
reduced pressure. Acetylation was carried out with pyridine/
acetic anhydride (1:1) at 25 °C for 48 h.