【作者】 李腾； 刘玥； 刘海超；

【Author】 Teng Li;Yue Liu;Haichao Liu;Beijing National Laboratory for Molecular Sciences,College of Chemistry and MolecularEngineering,Green Chemistry Center,Peking University;

【机构】 北京大学化学与分子工程学院绿色化学研究中心北京分子科学国家实验室；

【摘要】 葡萄糖异构化为果糖是纤维素转化过程中至关重要的一步[1]。酸作为葡萄糖异构化的催化剂,特别是多相Lewis酸,如Sn-Beta[2]和USY[3],引起了人们的关注。本文采用高温或水汽处理的H-Beta分子筛催化剂,可以高效地催化甲醇中葡萄糖异构化反应。利用甲醇中果糖比葡萄糖更容易形成糖苷的特性,促进葡萄糖异构为果糖反应[4],获得了~81%的果糖产率。催化剂的表征结果表明糖苷生成的主要活性位为Br?nsted酸,而具有特定铝配位的Lewis酸催化异构化反应。更多还原

【Abstract】 Isomerization of glucose to fructose is a key step for cellulose conversion to some important chemicals(e.g. propylene glycol). For this reaction, solid Lewis acids, such as Sn-Beta and USY, have been studied in the literature. In this work, we found that H-Beta can catalyze this reaction efficiently. The equilibrium of the isomerization reaction is shifted towards fructose because the fructoside is formed more easily than glucoside in methanol. The yield of the fructose(fructoside) reaches up to ~81%. It is proved that the active sites for the glycoside formation are the Br?nsted acid sites on H-Beta while the Lewis acid sites with specific Al coordination structure catalyze the isomerization reaction.更多还原