Solvent-free condensation of ethyl levulinate with phenol promoted by Amberlyst-15: Kinetics and modeling

In the present work, a catalytic screening using the most common heterogeneous acid catalysts was conducted, using as a raw material ethyl levulinate. Extensive catalyst screening revealed that Amberlyst-15 can be considered a very suitable catalyst to promote the DPE synthesis from ethyl levulinate and phenol. The use of ethyl levulinate allowed to obtain 100% selectivity towards p,p-DPE isomer, a precursor for the NIPU synthesis. A kinetic investigation was conducted to determine the influence of different parameters on the reaction rate. Finally, a mathematical model with intraparticle diffusion limitations was employed to describe the experimental data and to retrieve the kinetic as well as adsorption parameters via non-linear regression analysis.