Titania-supported sub-nanometer sized Ru-Ni catalysts for the hydroxymethylfurfural hydrodeoxygenation
Agnieszka M. Ruppert, Magdalena Brzezińska, Nicolas Keller
Abstract
Biomass derived 2,5-dimethylfuran (DMF) is a source of biobased polymers or fuels. Key to its selective production lies in the design of efficient and stable heterogeneous catalysts. In our work we showed for the first time how the modification of a finely dispersed Ru catalyst prepared by a photon-assisted synthesis with the addition of Ni allows for the elaboration of a bimetallic Ru-Ni/TiO2 catalyst with boosted performances in the 5-hydroxymethylfurfural (HMF) hydrogenation to DMF. This catalyst modification influenced the electronic properties of Ru, the particle size and the metal-support interaction, that resulted in an increase in the surface acidity of the catalyst and in the improvement of the catalytic performance. We evaluated the importance of several factors, in particular the role of a Ru-Ni interaction, the particle size change or the presence of interfacial Ru-TiO2 sites, on the activity performance of the TiO2 supported bimetallic catalysts. Those combined factors led to a volcano-like efficiency curve, with an optimum catalyst displaying an equimolar Ru:Ni molar ratio.