Dehydrogenation of Diethylene Glycol to Para-Dioxanone over Cu/SiO2 Catalyst: Effect of Structural and Surface Properties

Para-dioxanone, a typical monomer for high-performance biomedical polymers, is generally obtained from the catalytic dehydrogenation of diethylene glycol. In this work, Cu/SiO2 catalysts were prepared by two different methods and applied in diethylene glycol dehydrogenation. The effects of catalyst properties on the performance of para-dioxanone production were systematically explored by combined techniques. The results showed that the high specific surface area and regular pore structure of the catalyst promoted and stabilized the high dispersion of the copper species with an abundant Cu-Si interface, thereby providing numerous reactive sites. The appropriate Cu0/Cu+ ratio in the active components produced efficient synergy, which was responsible for the excellent dehydrogenation performance. In addition, the low surface acid density (0.532 μmol/m2) of the catalyst greatly reduced the occurrence of diethylene glycol dehydration, thus improving para-dioxanone selectivity over 90% with promising stability.