Characterization of NiFe alloy phases in nanoparticles used as selective catalysts for the production of furfuryl alcohol from furfural hydrogenation

Abstract

It is well known that the selectivity toward different products in furfural hydrogenation can be changed when Ni catalysts are promoted with Fe. To achieve this effect, both elements must be sufficiently close to each other to allow and modify the carbonyl group adsorption mode. This condition is fulfilled if Ni and Fe are alloyed. In this study, the presence of these alloys was confirmed using Mossbauer ¨ spectroscopy at 298 and 13 K on freshly reduced catalysts, where three distinct alloy phases were identified. This result was further supported by TPR assays. This is the first report indicating that the co-impregnation preparation leads to this heterogeneity in the catalysts. To verify the effect of these Ni-Fe alloys, the selectivity and activity in furfural hydrogenation were analysed. The changes in the production of furfuryl alcohol, tetrahydrofurfuryl alcohol and furan using a Ni monometallic catalyst and three bimetallic catalysts with different Fe loadings, were observed. The amount of furfuryl alcohol obtained increased significantly with the addition of Fe.