废瓦楞纸纤维素酶解条件及酶解时纤维结构的变化

Conditions of Enzymolysis of Cellulose from Waste Corrugated Paper and Modification of Fiber Structure during Enzymolysis

研究了酶解条件对废瓦楞纸纤维素酶水解产葡萄糖的影响、酶解时的纤维结晶度与微观结构的变化。结果表明,在最优的酶解条件下,即温度50℃、pH值4.8、酶剂量80 FPU/g(以底物计)、底物质量浓度100 g/L,水解36 h后,水解液中葡萄糖质量浓度达53.8 g/L,纤维素水解率76.9%。结晶度分析表明,纤维素酶解分为两个阶段:首先主要水解无定形区,结晶度上升;然后同时水解无定型区和结晶区,结晶度基本维持稳定。扫描电镜观察显示,酶解时纤维出现层层的"剥皮"、断裂并出现中空,结构完全被破坏。

The effects of conditions of enzymolysis of cellulose from waste corrugated paper on glucose production, as well as the variation of crystallinity and microstructure of fibers during enzymolysis are investigated. The optimum conditions of temperature 50 ℃, pH value 4.8, enzyme loading 80 FPU/g and substrate concentration 100 g/L, after 36 h of hydrolysis, 53.8 g/L of glucose concentration and 76.9 % of cellulose hydrolysis efficiency are obtained. The modification of erystallinity of fibers during hydrolysis is carried out in two stages. Hydrolysis mainly occurs at amorphous region firstly, causing the increase of crystallinity. Then the hydrolysis of both amorphous and crystallinic regions occurs, resulting in the crystallinity keeping stable. The photos of scanning electronic microscopy show that during hydrolysis the fragments are decorticated from the fibers, in succession the fibers are broken off and become hollow, and the structure of the fibers is completely destroyed.