Pt/Nb2O5-Al2O3 Catalysts for the Hydrogenation and Reductive Amination of Furfural

Furfural is a well-recognized biomass platform. Hydrogenation and reductive amination of furfural are two principal routes in the valorization of this compound. In both reactions, the presence of reducible species (SMSI effect) and acid sites could favor the selectivity toward some interesting products. Both conditions could be obtained using metal particles supported on reducible mixed oxides. In this work, we investigate the use of Pt/Nb2O5-Al2O3 catalysts for the hydrogenation and reductive amination of furfural at distinct Nb2O5 contents. A decaniobate salt was used as a precursor of Nb2O5. The solids were reduced at 500 degrees C to assure the migration of reducible NbOx species. The solids were characterized by XRD, Raman spectroscopy, HR-TEM, N-2-physisorption, NH3-TPD and Pyr-DRIFTS. The results showed that higher Nb2O5 loadings led to a lower distribution of Al2O3 and Pt, favoring the catalysts' acidity. This fact implies that large particle size and the presence of Nb2O5 islands favor the formation of furfuryl alcohol but have a detrimental effect on the amine formation in the reductive amination of furfural.