酸性阳离子交换树脂催化降解木质纤维素制备可还原糖

为研究木质纤维素中不同组分的降解规律,以自制强酸性阳离子交换树脂为催化剂,对秸秆、蒸汽爆破预处理秸秆和微晶纤维素(MCC)进行降解处理研究。考查了催化剂用量、反应温度、反应时间等对秸秆降解反应的影响,比较了纤维素和半纤维素降解效果。研究结果表明,在微波加热条件下,以离子液体Amim]Cl为溶剂时,当催化剂与木质纤维素质量比为1∶1、反应温度为140~160℃、反应时间为20~40 min时,总还原糖收率最高可达92%且半纤维素较纤维素易于降解,在140℃反应30 min,木糖收率最高为47.3%,在160℃反应40 min,葡萄糖收率最高可达45.8%。比较木屑、蒸汽爆破预处理的木屑和微晶纤维素催化降解情况,结果表明,酸性阳离子交换树脂对它们均具有有效的催化效果,其中微晶纤维素降解效果最好。

Degradation of lignocellulose for preparing reducing sugar catalyzed by acidic cation exchange resin

In order to learn the degradation pattern of different components of lignocellulose, we used self-made acidic cation exchange resins to catalyze the hydrolysis of straw, straw pretreated with steam-explosion and microcrystalline cellulose in this study. The effects of catalyst dosage, reaction temperature and time on the degradation of straw were studied in detail, and the results of cellulose and hemicellulose hydrolysis were compared. The results indicated that using resin as the catalyst and ionic liquid Amim]Cl as the solvent, the straw can be converted with the highest TRS yield of 92% under the conditions of m_{lignocellulose}:m_cat=1, and reaction temperature between 140 and 160℃ under microwave-assisted heating for 20-40 min. Hemicellulose is more susceptible to degradation compared with cellulose. The xylose yield was 47.3% when the reaction was heated at 140℃ for 30 min and the glucose yield was 45.8% when the reaction was heated at 160℃ for 40 min. The degradations of different lignocellulose were investigated. The results indicated that the acidic cation exchange resin is an efficient catalyst for the degradation of lignocellulose and the result of microcrystalline cellulose degradation is the best.