When washed pulps is milled and ground to a fine powder, the resulting material may easily be degraded by cellulolytic enzymes. The klason and UV lignin content of the solid residuals obtained in this step were 49.9 %...When washed pulps is milled and ground to a fine powder, the resulting material may easily be degraded by cellulolytic enzymes. The klason and UV lignin content of the solid residuals obtained in this step were 49.9 % lignin for spruce KP, and 21.4 % for poplar KP. The solid residuals from enzymatic treatment contained about 93.3 % and 90.7 % of the lignin originally presented in the spruce KP and poplar KP respectively. The enzymatic treated residual was then subjected to mild acidolysis, which caused the cleavage of lignin-carbohydrate linkages. The resulting Ground Enzymatic/Acidolysis Kraft Lignin (GEA-KL) is of significantly higher yield than our previous two-step (enzymatic/acidolysis) residual kraft lignin (EA-KL). The improved method offers kraft lignin preparations in higher yield and purity than any other known method with minimal work up and solvent requirements. DFRC/quantitative 31P NMR protocol and quantitative DEPT edited 13C RMR were used for characterizing of RKLs.展开更多
文摘When washed pulps is milled and ground to a fine powder, the resulting material may easily be degraded by cellulolytic enzymes. The klason and UV lignin content of the solid residuals obtained in this step were 49.9 % lignin for spruce KP, and 21.4 % for poplar KP. The solid residuals from enzymatic treatment contained about 93.3 % and 90.7 % of the lignin originally presented in the spruce KP and poplar KP respectively. The enzymatic treated residual was then subjected to mild acidolysis, which caused the cleavage of lignin-carbohydrate linkages. The resulting Ground Enzymatic/Acidolysis Kraft Lignin (GEA-KL) is of significantly higher yield than our previous two-step (enzymatic/acidolysis) residual kraft lignin (EA-KL). The improved method offers kraft lignin preparations in higher yield and purity than any other known method with minimal work up and solvent requirements. DFRC/quantitative 31P NMR protocol and quantitative DEPT edited 13C RMR were used for characterizing of RKLs.
