Interactions between cellulose and lignin during hydrolysis in subcritical water

The interactions between cellulose and lignin, and the hydrolysis behavior of cellulose, lignin and cellulose-lignin mixtures with mass ratios of 25/75, 50/50, 75/25 in subcritical water were investigated in this study. Cellulose and lignin interactions greatly promoted the hydrolysis of lignin during hydrolysis of the cellulose-lignin mixture with a mass ratio of 25/75, whereas they accelerated and suppressed lignin hydrolysis in the other cellulose-lignin mixtures at reaction temperatures under and above 257 degrees C, respectively. The cellulose and lignin interactions presented negative effects on cellulose hydrolysis in all the samples at reaction temperatures higher than 257 degrees C. However, they showed positive and negative effects in the cellulose-lignin mixture with a mass ratio of 25/75, and the cellulose-lignin mixtures with mass ratios of 50/50 and 75/25, respectively, at reaction temperatures under 257 degrees C. The cellulose and lignin interactions also suppressed the heat-related re-actions and the glucose and aromatic-linked polymer char formation reactions.