N-substituted furfuryl amines are an important class of compounds due to their pharmaceutical activities that can be produced by reductive amination of furfuraldehydes derived from biomass. With supported Pd nanoparticles it is possible to obtain high activities and selectivities for the production of secondary amines. CO adsorption monitored by IR show the importance of the Pd crystal size and crystal face on catalyst activity and selectivity. When using Pd on carbon the amount of unsaturated Pd sites is very much enhanced with the corresponding increase in selectivity. The role of carbon deposition on metal terraces on catalytic selectivity is discussed. The optimized catalyst has been successfully applied in the reductive amination of 5-hydroxymethylfurfural with different amines and ammonia as well as in the one-pot reductive amination starting from nitrobenzene instead of aniline, giving the different N-substituted-5-(hydroxymethyl)-2-furfuryl amines with excellent activity and selectivity.

Ruthenium nanoparticles with a core-shell structure formed by a core of metallic ruthenium and a shell of ruthenium carbide have been synthesized by a mild and easy hydrothermal treatment. The dual structure and composition of the nanoparticles have been determined by synchrotron XPS and NEXAFS analysis and TEM imaging. At increasing sample depth, metallic ruthenium species start to predominate, according to depth profile synchrotron XPS and XRD analysis. The herein ruthenium carbon catalyst is able to activate both CO2 and H2 showing exceptional high activity for CO2 hydrogenation at low temperatures (160-200 °C) with 100% selectivity to methane, surpassing by far the most active Ru catalysts reported up to now. Based on catalytic studies and isotopic 13 CO/ 12 CO2/H2 experiments, the active sites responsible for the unprecedented activity can be associated to those surface ruthenium carbide (RuC) species, enabling CO2 activation and transformation to methane via direct CO2 hydrogenation mechanism. The high activity and absence of CO in the gas effluent confers this catalyst interest for the Sabatier reaction, a reaction with renewed interest for storing surplus renewable energy in the form of methane.

Biomass platform molecules such as glycerol and 5-hydroxymethylfurfural have been valorized into diol monomers by acetalization reaction in the presence of tridirectional large pore zeolites (HY and Beta), a laminar zeolite (ITQ-2) and a mesoporous aluminosilicate (MCM-41) and a conventional homogeneous acid catalyst (p-toluenesulfonic acid). The influence of the solvent polarity, pore structure, hydrophobic character and acidity of the catalyst on the activity and selectivity to HMF glyceryl acetals has been studied. Results showed that while the homogeneous catalyst mainly promotes polymerization reactions, tridirectional zeolites are more active catalysts but less selective and deactivate more rapidly than mesoporous MCM-41 and delaminated 2D zeolites. ITQ-2 and MCM-41 catalysts with smaller confinement effects, easy diffusion, and adequate surface polarity provide high yield (98 %) and selectivity (100%) to the target compound. These catalysts are stable and allow regeneration and reuse.