Production of Biofuels by 5-Hydroxymethylfurfural Etherification Using Ion-Exchange Resins as Solid Acid Catalysts

Nowadays, the development of catalytic technologies to transform biomass-derived platform molecules, like 5-hydroxymethylfurfural (5-HMF) obtained from the dehydration of C6 carbohydrates (glucose, fructose, galactose, among others), into valuable products with interesting industrial and commercial applications, is attracting the interest of many research groups. Thus, for instance, 5-ethoxymethylfurfural (EMF), which can be produced from the etherification of 5-HMF with ethanol, can be mixed with petro-diesel, being considered as one of the most promising furan derivatives, not only as diesel additive but also as a biofuel. In this context, this communication deals with the evaluation of the catalytic performance of different commercial ion-exchange resins, as solid acid catalysts, in this etherification reaction. The objective was to elucidate the role of acid sites (type: Lewis and/or Brönsted, concentration and strength) in this catalytic process. Moreover, it must be taken into account that the etherification of 5-HMF into EMF also generates, as the main sub-product, ethyl levulinate, that can also be produced by esterification of levulinic acid and ethanol through acid catalysis. The most relevant experimental parameters will be optimized in order to achieve the highest EMF yield. Moreover, special attention will be paid to develop active, selective and stable heterogeneous catalysts.