Highly selective dehydrogenation of methanol to methyl formate over copper catalysts supported on hierarchical hollow silica spherical

In the methanol dehydrogenation to methyl formate (MF), it is of primary importance to improve the selectivity toward MF through inhibiting decomposition of methanol to CO and H 2 . Herein, the copper catalysts supported on hierarchical hollow silica spherical (HHSS) were synthesized by the ammonia assisted deposition precipitation (ADP) method and tested in the reaction. The 5Cu/HHSS catalyst exhibits the superior activity with a turnover frequency (TOF MF ) value, while 10Cu/HHSS shows the optimal MF selectivity of 98.1 %. It is found that there is a positive correlation between TOF MF and Cu dispersion, as well as between MF selectivity and Cu 0 concentration. Thanks to the unique structure of HHSS with large cavities and abundant mesopores, the ADP method can facilitate a high dispersion of copper on silica and promotes the formation of more active Cu 0 sites, which therefore results in superior activity and MF selectivity of the Cu/HHSS catalysts in the methanol dehydrogenation to MF.