EFFECT OF REFINING ON ENZYMATIC HYDROLYSIS OF GREEN LIQUOR PRETREATED MIXED HARDWOOD

摘要

The effects of refining on improving enzymatic hydrolysis was investigated using green liquor (the mixture of sodium carbonate and sodium sulfide, GL) pretreated mixed southern hardwood at 12% total titratable alkali (TTA) charge. The sugar yield rises up with the increase of PFI revolution. The effect of 1% NaOH addition during refining on pulp freeness is little, but it could effectively improve the sugar yield of enzymatic hydrolysis. Compared with controlled GL pretreated pulp without refining, a remarkably increase in sugar yield could be achieved at a low enzyme loading after the pulp was refined by a PFI mill. Meanwhile, an obvious increase in sugar yield could be obtained in the initial 6 or 12 hours of enzymatic hydrolysis at the same cellulase loading after pulp was refined by PFI mill. The results indicate that refining is of great feasibility to increase the accessibility of the cellulose and improve the enzymatic hydrolysis of lignocellulosic biomass.