锰改性氧化硅负载金催化剂用于醇气相选择性氧化的研究

The study of gold catalyst supported on manganese oxide modified SiO2 for gas-phase selective oxidation of alcohol

摘要:

为实现醇的高效气相选择性氧化，以四氧化三锰改性的氧化硅为载体制备了负载型金催化剂。实验结果表明，氧化硅经过四氧化三锰改性后，苯甲醇转化率和选择性明显提高。通过进一步调节四氧化三锰和金的负载量，可以实现醇的高效气相选择性氧化。当反应温度为250℃时，苯甲醇转化率和选择性可分别达到96%和98%。采用X射线粉末衍射(XRD)和透射电镜(TEM）等手段对催化剂进行了表征，结果表明，低负载量的四氧化三锰在氧化硅表面实现了单层分散，金颗粒粒径为12-14 nm，但是由于金和单层分散的四氧化三锰之间的相互作用，使得该催化剂体现出良好的醇气相选择性氧化催化性能。

Abstract:

In order to achieve the highly-effective gas-phase selective oxidation of alcohols, the gold catalyst was prepared using Mn3O4-modified SiO2 as support, and the modification conditions of support, the preparation and reaction conditions of catalyst were investigated. The results showed that benzyl alcohol conversion and benzaldehyde selectivity were enhanced over the modified catalyst. For example, benzyl alcohol conversion of 96% and benzaldehyde selectivity of 98% could be achieved at 250℃. The catalysts were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM), and the results showed that the Mn3O4 was dispersed in the form of monolayer. Gold particle size is 12-14 nm, but exhibits excellent performance for the alcohol oxidation due to the Au-Mn3O4 interaction.