Recovery of lignin and ionic liquid by using organic solvents

[Display omitted] Studies of lignin and ionic liquid separation by using an organic solvent were investigated. Effects of main factors including solvent type and amount, separation temperature on product yield, and purity were examined. Solvents show their different separation effectiveness, the most effective solvent for lignin–ionic liquid separation is isopropanol. An attempt to enhance efficiency of single-stage separation was also carried out by using multi-stage separation. TGA data, 1H NMR and SEM images indicate that chemical and thermal properties of recovered ionic liquid and precipitated solid from multi-stage separation are comparable with those of fresh materials.