Continuous-Flow Hydrogenation of D-Xylose with Bimetallic Ruthenium Catalysts on Micrometric Alumina

Continuous-flow hydrogenation of D-xylose to xylitol was evaluated with pristine and silver modified ruthenium supported on micrometric alumina. The original size of alumina support is required for direct use in flow hydrogenation since it prevents setup clogging. The parent ruthenium catalyst shows high activity and selectivity to the desired product. However, there was an evident competition between adsorption of substrate and product desorption, and ruthenium nanoparticles aggregation. In situ modification of the parent catalyst with silver improved catalysts stability and minimize the competitive adsorption behavior between reactant and product.