High-Entropy Oxides derived Cu catalyst for enhanced dehydrogenation of cyclohexanol coupling with hydrogenation of acetone

Abstract

Dehydrogenation of cyclohexanol to cyclohexanone is a vital step during the manufacture of nylon, but this endothermic reaction is unfavorable at a low temperature. In this work, high entropy oxides (Cu0.75Zn0.15Mg7.1Al1Sc1O11-HEO) was synthesized from a well-structured Cu0.75Zn0.15Mg7.1Al1Sc1(OH)20CO3 layered double hydroxide. Characterization results disclosed that Cu0.75Zn0.15Mg7.1Al1Sc1O11-HEO possesses large specific surface area (157 m2/g), enhanced basicity and Cu dispersed highly in the framework of HEO (74.0%). The reduced Cu0.75Zn0.15Mg7.1Al1Sc1O11-HEO catalyst was highly active and stable for the dehydrogenation of cyclohexanol than those Cu-based catalysts prepared from binary, ternary, and quaternary mixed metal oxides. More interestingly, the conversion of cyclohexanol could be enhanced obviously when acetone was selected as the solvent and/or hydrogen acceptor. It was confirmed that the addition of acetone could enhance the yield of cyclohexanone and simultaneously hydrogenation of acetone to isopropanol.