Effect of the ZrO₂ Crystal Phase on Performance over a CuCeZrO Catalyst for Dehydrogenative Condensation of Ethanol to Ethyl Acetate

Ethyl acetate is an important chemical, and ethanol dehydrogenative condensation with 95.6% atomic economy is a promising synthetic route. CuZrO-based catalysts are widely applied in this reaction; however, the effect of the ZrO₂ crystal phase in the CuCeZrO catalyst upon reaction deserves to be explored further. Herein, the ZrO₂ crystal phase in the CuCeZrO catalyst was regulated by controlling the calcination temperature, and a high temperature (≥600 °C) is conducive to the transformation of the tetragonal phase to the monoclinic phase. Additionally, monoclinic ZrO₂ (<i>m</i>-ZrO₂) with limited density of the strong base is found to be more beneficial to the selective production of ethyl acetate from ethanol, while tetragonal ZrO₂ (<i>t</i>-ZrO₂) with abundant strongly basic sites is more inclined to the formation of butanol and its downstream esters. This work not only improves our understanding of the crystal phase effect in a CuCeZrO catalytic system but also paves the way for the development of more efficient catalysts for ethyl acetate production.