Promotional effect of Ce on selective hydrogenation of cinnamaldehyde over PtTi catalysts
摘要
A series of PtCexTiy catalysts with 1 wt% Pt loading were synthesized and evaluated for the selective hydrogenation of cinnamaldehyde (CAL) to cinnamyl alcohol (COL). The introduction of an optimal amount of Ce into TiO2 facilitated the formation of Ce–O−Ti structures, which promoted the reduction of Pt species and enhanced their dispersion. Moreover, Ce incorporation significantly increased both the number and stability of Lewis acid sites on the catalyst surface. These sites play a key role in the selective activation of the C=O group and facilitate the targeted addition of hydrogen to this bond. The high catalytic performance is attributed to the highly dispersed Pt⁰ species, abundant surface vacancies, and the presence of beneficial Lewis acid sites, which collectively enhance the adsorption and activation of the C=O bond in CAL. In addition, strong metal–support interactions between Pt and the Ce-Ti carrier contributed to outstanding catalytic stability, as demonstrated by the PtCe2Ti3 catalyst maintaining high activity over five consecutive reaction cycles.
Graphical abstract