Conversion of Ethanol to n-Butanol over NiCeO2 Based Catalysts: Effects of Metal Dispersion and NiCe Interactions

Conversion of ethanol to n-butanol is of great significance in ethanol upgrading, and multiple sites of metals and oxides are generally coupled for this cascade reaction. Herein, we dispersed Ni and CeO2 sites on different carbon supports with the aim of getting insight into the effect of metal dispersion and interactions on the conversion of ethanol to n-butanol. Our results revealed that the dispersion of Ni and CeO2 was crucial to ethanol conversion and n-butanol selectivity. The activated carbon (AC) had a high specific surface area and abundant surface functional groups, which benefited the dispersion of Ni and CeO2 species and created balanced Ni-0/Ni2+ sites, weak acid and strong base sites for the hydrogen transfer and aldol condensation reactions. Additionally, the stability of catalyst was determined by the interaction between Ni and CeO2 species. Over the NiCeO2/AC catalyst, Ni and CeO2 species strongly interacted, which depressed the carbonation of CeO2 and maintained its high stability.