Highly selective and low-temperature hydrothermal conversion of natural oils to fatty alcohols

In this contribution, we report a facile and green process for the quantitative transformation of natural oils, fatty esters, and fatty acids to fatty alcohols over N-modified carbon (N-C) supported RuSn catalysts in water at low temperatures (140-180 °C). The synthesis of the N-C support was carried out by using a one-pot process with melamine, glucose, and ZnCl₂ as reactants. The presence of Sn nanoparticles, and pyridinic and pyrrolic nitrogen in the modified N-C support favoured the good dispersion of Ru nanoparticles, improved the hydrophilic properties of the catalyst for staying in the water layer, and facilitated the adsorption of the carbonyl groups. After strongly interacting with the carbonyl group of fatty acids over Sn nanoparticles and N-groups, Ru nanoparticles catalysed the further acid hydrogenation to the intermediate aldehyde, and subsequently to the target fatty alcohol at a fast rate. This provides a useful and simple method for synthesizing highly hydrothermal-stable metal supported carbon catalysts, which can facilely and selectively hydrogenate the aqueous biomass to value-added chemicals.