Fractionation of Organosolv Lignin Using Acetone:Water and Properties of the Obtained Fractions. ...

Lignin fractions with different molecular weight were prepared using
a simple and almost green method from switchgrass and pine organosolv lignin.
Different proportions of acetone in water, ranging from 30 to 60%, were used for
lignin fractionation. A higher concentration of acetone dissolved higher molecular
weight fractions of the lignin. Fractionated organosolv lignin showed different
molecular weight and functional groups. Higher molecular weight fractions
exhibited more aliphatic and less phenolic OH than lower molecular weight
fractions. Lower molecular weight fractions lead to more homogeneous structure
compared to samples with a higher molecular weight. All fractions showed strong
antioxidant activity