Abstract:
A series of Ce-modified Ru/HAP catalysts with different loadings were prepared by impregnation method, which were applied to the one-step preparation of 2, 5-furandicarboxylic acid with fructose. The catalysts were characterized by XRD, TEM, NH
3-TPD and XPS. The results showed that Ce was highly dispersed on the HAP, and the addition of Ce affected little on the structure of HAP. Ce mainly exists in the form of Ce
3+ and Ce
4+. The presence of the Ce
3+ makes a large amount of oxygen holes on the surface of the catalyst, and the electron transfer between Ce
3+ and Ce
4+ is conducive to the formation of oxygen holes, improves the oxygen storage capacity and the surface catalytic activity. The catalyst is rich in weak acid sites, which inhibits the side reactions. Among the catalysts evaluated, the sample of Ce (8%, mass ratio) -Ru/HAP showed satisfied performance with the 2, 5-FDCA yield of 34.2% at 160℃ for 4 h reaction under a pressure of 2 MPa and a catalyst dosage of 0.1 g. Therefore, the introduction of Ce has greatly improved the catalytic activity of traditional precious metal composite catalysts, and also provided new ideas for the one-step preparation of fructose 2, 5-FDCA.