摘要
以无水四氯化锆Zr Cl4和不同的有机配体,如苯二甲酸、2-硝基苯二甲酸和1,2,4-苯三甲酸为原料,DMF为溶剂,通过溶剂热法合成了一系列Ui O-66(Zr)的金属有机骨架MOFs,并用于催化转化二羟基丙酮至乳酸乙酯的反应。Ui O-66(Zr)的催化活性和乳酸乙酯的选择性可以通过在制备过程中采用含有不同吸电子基团的无机配体来调节。而且当使用反应中间产物丙酮醛作为起始反应物时,MOFs的活性有了显著的提高。材料表征结果显示,Ui O-66(Zr)系列MOFs材料中Br?nsted酸的含量低但强度较大,而Lewis酸的含量则较高。本文对二羟基丙酮转化为乳酸乙酯的反应机理进行了详细分析,并实现了100%的二羟基丙酮转化率和乳酸乙酯选择率。
A serious of Zr-terephthalates metal-organic frameworks [UiO-66（Zr）] were synthesized by solvothermal method starting from a solution of ZrCl4 and different organic ligands,such as terephthalic acid,2-nitroterephthalic acid,and 1,2,4-benzenetricarboxylic acid,dissolved in DMF. These materials were investigated as heterogeneous catalysts for the conversion of dihydroxyacetone into the valuable compound,ethyl lactate. The catalytic activity and selectivity towards ethyl lactate of UiO-66（Zr） materials can be easily tuned by using linkers with different electron withdrawing groups in the synthesis mixture. When pyruvic aldehyde,the intermediate product of the conversion reaction, was applied as the starting reagent,the activity of the MOFs was significantly improved. Characterization shows that the Br-nsted acid in the MOFs is strong but with low amount;however, the number of Lewis acid sites is higher. For the conversion of dihydroxyacetone,the reaction mechanism was fully explored and a complete substrate conversion with full selectivity towards ethyl lactate was achieved with the studied catalysts.
出处
《化工进展》
EI
CAS
CSCD
北大核心
2015年第11期3938-3943,3950,共7页
Chemical Industry and Engineering Progress
