乙酸预处理对相思木酶解糖化及物化性能的影响

Effects of Acetic Acid Pretreatment on Enzymatic Saccharification and Physical and Chemical Properties of Acacia

关键词:  相思木  乙酸预处理  酶解糖化  物化性能

Key Words:acacia  acetic acid pretreatment  enzymatic saccharification  physical and chemical properties

摘要:通过对木片进行乙酸预处理、三段磨浆及PFI磨浆,探讨预处理温度、乙酸用量、PFI打浆转数对相思木酶解糖化率的影响,并采用X射线衍射仪、扫描电子显微镜、热重-红外联用仪对预处理前后相思木结构进行分析。结果表明,乙酸预处理可显著提高相思木乙酸提取液中的还原糖得率与固形物含量,且预处理后底物的酶水解糖得率也呈现不同程度的上升趋势。在一定条件下,预处理温度越高、乙酸用量越大或PFI打浆转数越多,预处理及酶水解转化过程中的总还原糖得率越高,对应原料失重也越高。此外,经乙酸预处理后,木片的微观结构和化学组成也发生明显改变。

Abstract:The effects of pretreatment temperature, acetic acid dosage and PFI revolutions on the enzymatic saccharification rate of acacia were discussed by acetic acid pretreatment, three-stage refining and PFI refining of wood chips. The structures of acacia before and after pretreatment were analyzed by XRD, SEM and TG-IR. The results show that acetic acid pretreatment can significantly increase the reducing sugar yield and solid content in the acetic acid extract of acacia, and the enzymatic hydrolysis sugar yield of the substrate after pretreatment also shows an upward trend to varying degrees. Under certain conditions, the higher the pretreatment temperature, the greater the acetic acid dosage or the more the PFI beating revolutions, the higher the total reducing sugar yield in the pretreatment and enzymatic hydrolysis conversion process, and the higher the weight loss of the corresponding raw materials. In addition, after acetic acid pretreatment, the microstructure and chemical composition of wood chips also change significantly.