Novelty of Claisen–Schmidt condensation of biomass-derived furfural with acetophenone over solid super base catalyst

Abstract

Valorization of biomass into value added chemicals and products using green technologies has been a subject matter of several papers. Claisen–Schmidt condensation of furfural with acetophenone to produce the α,β-unsaturated keto compound, 3-(furan-2-yl)-1-phenylprop-2-en-1-one, is commercially attractive since it is used in the pharmaceutical industry and can be hydrogenated to give high quality diesel fuel. In the current work, preparation and characterization of 5–15% w/w Al₂O₃ on CaO was done using FT-IR, TGA, XRD, SEM, EDXS, TPD and nitrogen BET. It was used in the reaction of furfural with acetophenone and its activity and selectivity were compared with other catalysts in a batch reactor at 120 °C. 15% w/w Al₂O₃/CaO was the best catalyst. It was 100% selective towards the formation of 3-(furan-2-yl)-1-phenylprop-2-en-1-one. The catalyst is robust and can be reused without loss of activity. The kinetics of the reaction follow the Langmuir–Hinshelwood–Hougen–Watson mechanism with weak adsorption of all species leading to typical second order kinetics. The apparent energy of activation is 12.5 kcal mol⁻¹.