摘要
以九水合硝酸铬和单磺酸钠对苯二甲酸为原料,水为溶剂,采用水热法合成系列磺酸功能化MIL-101(Cr),通过调节反应温度和时间,合成不同Lewis/Br?nsted催化位点比例的磺酸功能化MIL-101(Cr),采用PXRD、EDX、SEM、ICP-AAS及BET比表面积分析等技术对材料进行综合表征,并研究磺酸功能化MIL-101(Cr)催化葡萄糖脱水制备5-羟甲基糠醛的催化活性。催化反应动力学研究结果表明,MIL-101(Cr)-SO3H中的Cr(Ⅲ)作为葡萄糖异构化反应的Lewis酸位点,-SO3H作为果糖脱水反应的Br?nsted酸催化位点,当催化剂的Br?nsted酸和Lewis酸的摩尔比为1.1时,150℃下反应,5-羟甲基糠醛的选择性最高可以达到47.15%,5-羟甲基糠醛的产率最高达到46.0%。
A series of Cr-terephthalates metal-organic frameworks functionalized by sulfonic acid group（-SO3H） [MIL-101（Cr）-SO3H],featuring varied ratios of Lewis acid site to Br？nsted acid site,were synthesized by hydrothermal reaction method starting from Cr（NO3）3·9H2O and sodium 2-sulfoterephthalate under various conditions of temperature and reaction time.The catalysts were characterized by techniques of PXRD,EDX,SEM,ICP-AAS and BET surface area,and the catalytic performances for glucose conversion to 5-HMF were evaluated.It showed that,in terms of the catalysis kinetics,Cr3＋ serves as the Lewis acid sites of MIL-101（Cr）-SO3 H for glucose isomerization,and sulfonic acid group,the Br？nsted acid site for the fructose dehydration.The highest HMF selectivity of 47.15% and the highest HMF yield of 46.0% was achieved under conditions of molar ratio of Br？nsted acid site to Lewis acid site of 1.1,150℃ for 2 h.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2016年第7期2799-2807,共9页
CIESC Journal
基金
国家自然科学基金项目(21436010,21376205)
