桉木热水预水解过程中木糖反应动力学的研究

Reaction Kinetics of Xylose from Eucalyptus Hot Water Prehydrolysis

关键词:  桉木  热水预水解  半纤维素  反应动力学

Key Words:eucalyptus  hot-water prehydrolysis  hemicellulose  reaction kinetics

摘要:研究了桉木热水预水解生成木糖水解液的反应动力学，分别测定了不同热水预水解条件下木糖质量浓度及其降解产物糠醛的质量浓度。研究表明，以木糖质量浓度及糠醛的质量浓度为指标，确定桉木最佳热水预水解条件为：液比1∶8，水解温度170℃，保温时间105 min。此条件下，预水解液中木糖和糠醛质量浓度分别为7.97 g/L、1.74 g/L，桉木热水预水解生成木糖的反应活化能为72.62 kJ/mol。

Abstract:In this study, the reaction kinetics of xylose hydrolysate from eucalyptus autohydrolysis was investigated through analyzing mass concentrations of xylose and its degradation product furfural under different prehydrolysis conditions. The evaluated activation energy of xylose was 72.62 kJ/mol according to the established reaction kinetic equation. The optimization of experimental parameters including wood to liquor ratio, hydrolysis temperature, and time was accomplished to determine the optimized hydrolysis conditions as follows: wood to liquor ratio 1∶8, hydrolysis temperature 170℃, time 105 min. Under this condition, the mass concentrations of xylose and furfural in the hydrolysate were 7.97 g/L and 1.74 g/L respectively.