水溶性Fe3O4磁性纳米催化剂的合成及应用

利用对氨基苯磺酸氟硼酸重氮盐与Fe₃O₄磁性纳米粒子(MNPs)的偶联反应,非常方便地制备出表面含有磺酸基的Fe₃O₄磁性纳米粒子。 透射电子显微镜(TEM) 测试结果表明,粒子的平均粒径在 20 nm左右。 溶解性实验表明,该纳米粒子具有较好的水溶性,但不溶于常用的有机溶剂,因此可利用其磁性回收并循环使用。 将该纳米粒子用于催化羧酸与醇的酯化反应,产物酯的收率为71%~86%。 催化剂在酯化反应中的最优使用量为1.5%(质量分数)。 同时,该催化剂可催化果糖合成5-羟甲基糠醛(HMF),收率为32%。

Synthesis and Application of Water-Soluble Fe3O4 Magnetic Nano-catalyst

Fe₃O₄ magnetic nano particles(MNPs) with sulfonic acid groups on the surface were readily prepared via coupling reaction between 4-amino phenylsulfonic acid diazonium tetrafluoroborate and Fe₃O₄ nano particles. Transmission electron microscopy(TEM) images reveal that the average size of these acidic particles is about 20 nm. These acidic particles show good solubility in water, but they are insoluble in most of common organic solvents, allowing easy isolation and recycling of the particles by their magnetic property in catalytic reactions. In terms of application, when the acidic magnetic particles were used to catalyze esterification reactions between carboxylic acids and alcohols, moderate to high isolated yields(71%86%) of ester products were obtained. The optimized catalyst loading is 1.5%(mass fraction). Furthermore, 5-hydroxymethyl furfural(HMF) was also synthesized in a 32% yield from fructose utilizing the acidic magnetic particles as a catalyst.