Abstract:

A novel high·eficiency method named Enzymatic/Acidolysis was introduced to isolate lignin from kraft pulp and raw fiber materials,with the lignin named enzymatic/acidolysis lignin(EMAL)being isolated.The main factors that afect the enzymatic hydrolysis and acid hydrolysis stages dudng the isolation were then discussed in detail.It is revEMALed that the yield of EMAL is 2～3 times that of the traditional milled.wood lignin(MWL),and that EMAL is of a higher purity than MWL.It is also indicated by an alysis that there is no remarkable diference in structure between the EMAL from wood materials and the corresponding MW L. Ihe experiments also demonstrate that,as compared with the coresponding MWL,the EMAL from non·wood materials is of similar purity but faifly higher yield.

Key words: lignin, hydrolysis, isolation, enzymatic/acidolysis method, purity