achieved by bubbling N2 gas on the reaction vessel, to eliminate the water formed during the reaction.
Further on, the ionic liquid solution was filtered and then acidified with water at pH 2 with 72% (w/w) sulphuric acid, to recover the lignin from the ionic liquid.
The solution was centrifuged at 4000 rpm for 15 min. The recovered lignin and the residue separated in the filter were dried at 50 ºC.
Organosolv lignin solubility in the ionic liquid is of about 72%, while soda lignin solubility is of about 3.91%. The recovery of purified organosolv lignin from ionic liquid is of about 50%.