以总碱用量为12%(Na2O计)的绿液预处理的混合阔叶木浆为原料,探讨了PFI打浆处理对改善浆料酶水解效率的作用。结果表明:酶水解糖的得率随着PFI磨浆转数的增加而提高,其中葡聚糖得率的增加较木聚糖显著,在较低的酶用量下提高PFI磨浆转数有利于提高浆料的酶水解糖化得率; 经打浆处理的绿液预处理浆可以在较短的时间内大幅度提高酶水解糖总糖得率,随着酶水解时间的延长,得率的增值逐渐减小; 与清水介质比较,浆料在1% NaOH中磨浆对提高酶水解糖得率具有更好的促进作用。
Abstract
Green liquor consists of sodium carbonate and sodium sulfide and is readily available in any kraft mill. Effects of refining on improving enzymatic hydrolysis was investigated using green liquor pretreated mixed hardwoods at 12% total titratable alkali charge. The sugar yield increases with the PFI revolution. Adding 1% NaOH during refining did not affect on pulp freeness significantly, but could effectively improve the sugar yield of enzymatic hydrolysis. Compared with controlled green liquor pretreated pulp without refining, a remarkable increase in sugar yield was 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 h of enzymatic hydrolysis with the same cellulase loading after pulp refined by PFI mill. The results indicate that refining has a great feasibility for increasing the accessibility of the cellulose and improving the enzymatic hydrolysis of lignocellulosic biomass.
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基金
收稿日期:2012-01-21 修回日期:2013-06-04
基金项目:国家自然科学基金项目(31070512,31370571); 南京林业大学引进高层次人才和高层次留学回国人员科研基金项目
第一作者:金永灿,教授,博士。E-mail: jinyongcan@njfu.edu.cn。
引文格式:金永灿,Houmin Chang,Hasan Jameel,等. 打浆对绿液预处理阔叶木酶水解的促进作用[J]. 南京林业大学学报:自然科学版,2013,37(6):116-120.
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