Kinetic investigation of the heterogeneous synthesis of flavanone over MgO

The synthesis of flavanone was studied over a magnesium oxide solid catalyst in a batch reactor. The reaction scheme consists of the Claisen-Schmidt condensation of 2'-hydroxyacetophenone with benzaldehyde towards the formation of a 2'-hydroxychalcone intermediate and the subsequent isomerization of this intermediate to flavanone. An initial parametric study yielded a range of values for key experimental parameters (i.e., catalyst particle size and weight percentage and stirring rate) for which the batch reactor system operates in the kinetic regime. The kinetic investigation that followed indicates that over the MgO catalyst studied the Claisen-Schmidt condensation reaction follows first-order kinetics in 2-hydroxyacetophenone and half-order kinetics in benzaldehyde, while the 2'-hydroxychalcone isomerization follows first-order kinetics; activation energies of 40 and 48 kJ/mol were obtained for the two reactions, respectively.