Characterizing and using a new bi-functional catalyst to sustainably synthesize methyl levulinate from biomass carbohydrates

Abstract

In recent years, significant attention has been dedicated to converting biomass carbohydrates into alkyl levulinates (biofuel additives) in alcoholic media, in search of various cheap and active solid catalysts through relatively easy pathways and from non-dangerous precursors. The synthesis of methyl levulinate (ML) using a new Brønsted/Lewis acid sites catalyst was investigated, emphasizing the influence of three parameters (catalyst loading, the molar concentration of fructose in methanol, and reaction temperature) on the process. The synthetized catalyst, SO42−/TiO2–La2O3 coating Fe3O4, was characterized by different techniques (FT-IR, XRD, TGA, TEM-EDX, ICP-OES). The design of the ML synthesis experiment was carried out using the Box-Behnken technique, while the response surface methodology was applied to obtain the optimized process conditions. A mathematical model of the catalytic synthesis was built, based upon first principles, and the experimental time variation of the reaction mixture concentrations was used to find, through regression, the values of the constants of a newly proposed kinetic model.