The best conditions for the kinetic study of the ketalization reaction of glycerol with acetone for the production of solketal using zeolite H-BEA (SAR 19) as a catalyst were found through a fractional experimental design. To simplify the heterogeneous kinetics, by means of a smaller number of kinetic parameters to encompass all the kinetic terms toward the products and reagents, a reversible kinetic model was used. From the comparison between the experimental and calculated conversions, it was possible to analyze the accuracy of the estimations, providing a good way to apply statistical treatments to improve the calculated kinetic properties. Thereby, it is possible to calculate the equilibrium constants for a range of reactions performed across different temperatures (40−80 °C) as well as the forward reaction activation energy (44.77 kJ mol −1 ) and the reverse reaction activation energy (41.40 kJ mol −1 ). Moreover, 70−76% glycerol conversion was obtained using the same catalyst for five reactions, without wash or performing any other pretreatments in the catalyst between reactions. The solketal product has been studied as a green industrial solvent additive in gasoline and biofuels.

The kinetic of fatty acids esterification with ethanol utilizing niobium oxide catalyst (79.8% of NbO5 and 19.6% of water) for the production of biodiesel was analyzed through a reversible kinetic modeling for the determination of the kinetic and thermodynamic data of the reactions. The reactions were carried out with three kinds of fatty acids (stearic, palmitic, and lauric) with anhydrous and hydrated ethanol. From the kinetic study it was possible to calculate the theoretical equilibrium data which were compared to experimental data of each reaction. From the comparison between the experimental and calculated conversions it was possible to analyze the accuracy of the estimations, providing a good way to apply statistical treatments in the improvement of the kinetic and thermodynamic properties calculated.

Experimental and modeling studies in the catalytic hydrogenation of glucose and fructose were carried out for the production of sorbitol and mannitol on ruthenium and nickel catalysts. Ruthenium based catalyst showed better results when compared to the Ni-Raney catalyst, achieving close to 100% of reactant conversion after 3 h of reaction at 130°C and 750 psia conditions. The application of hybrid autocatalytic kinetic models for the reaction network of the formation of sorbitol and mannitol led to simulation results that represented the data obtained experimentally well. The autocatalytic terms were observed in the concentration profiles of sorbitol and mannitol. From the correlation between the experimental data and the simulation results of the autocatalytic kinetic models, it was possible to determine the kinetic parameters of the hydrogenation using both the nickel and ruthenium catalysts (Ni/Raney and Ru/Al 2 O 3 , respectively).

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