In cross-coupling of biomass-derived acetone and alcohols contributing to the production of carbon-elongated chemicals and fuels, the essential catalyst components are metal dispersion for alcohol dehydrogenation and, more importantly, basicity for carbon–carbon coupling. Herein, we report the potential of co-precipitated praseodymia–zirconia solid solution (Pr2Zr2O7) as a support of Cu catalyst for the conversion of acetone and butanol into C7 and C11 products. Cu/Pr2Zr2O7 exhibits a high yield of C7 and C11 (ca. 84%) compared to Cu/ZrO2 and Cu/PrO1.83. Moreover, it is robust under the employed solvent-free conditions owing to a solid solution of Pr2Zr2O7 compared to PrO1.83 showing phase transition to PrOHCO3. It is also tolerant to up to 5 wt % water of the reactant mixture, recyclable once adequate post-treatment is employed after the reaction, and can convert the acetone–butanol–ethanol mixture into C5–C11 products at the nearly equivalent yield (82%) to the acetone–butanol mixture. Therefore, the Cu/Pr2Zr2O7 reported herein is an efficient catalyst for the coupling of acetone with linear aliphatic alcohols into biofuel precursors.

The selective transformation of secondary alcohols to alpha-olefins is a challenging task in heterogeneous catalysis, as is the case of 4-methyl-2-pentanol (4M2Pol) conversion to 4-methyl-1-pentene (4M1P). Herein, the co-precipitated yttria-stabilized zirconia (YSZ) catalysts exhibit superior performance to both bare and Y-impregnated ZrO2 in selective 4M2Pol dehydration. In order to track the activity origin of YSZ, temperature-programmed desorption experiments using NH3 and CO2 are performed along with X-ray photoelectron spectroscopy. The conversion of 4M2Pol (max. 85%) is proportional to weak acidity and inverse to medium basicity. In contrast, the selectivity of 4M1P increases to 80% as the ratio of weak acidity to medium basicity is close to and exceeds the unity. These indications corroborate that the balanced acid–base pair of YSZ leads to the selective formation of 4M1P from 4M2Pol, which is caused by strong interaction between zirconia and yttria in the YSZ. Additionally, the dehydration activity over YSZ of 4 mol% yttrium is sustained at 450 °C for 50 h. Therefore, the YSZ, which is often used for electrocatalysis, is believed to be a promising catalyst in the dehydration of 4M2Pol and, further, secondary alcohols.