Abstract
The hydrogenation of levulinic acid has been studied using Ru
supported on ordered mesoporous carbons (OMCs) prepared
by soft-templating. P- and S-containing acid groups were introduced
by postsynthetic functionalization before the addition
of 1% Ru by incipient wetness impregnation. These functionalities
and the reaction conditions mediate the activity and selectivity
of the levulinic acid hydrogenation. The presence of Scontaining
groups (Ru/OMC-S and Ru/OMC-P/S) deactivates
the Ru catalysts strongly, whereas the presence of P-containing
groups (Ru/OMC-P) enhances the activity compared to that of
pristine Ru/OMC. Under mild conditions (70 8C and 7 bar H2)
the catalyst shows high selectivity to g-valerolactone (GVL;
>95%) and high stability on recycling. However, under more
severe conditions (200 8C and pH2=40 bar) Ru/OMC-P is particularly
able to promote GVL ring-opening and the consecutive
hydrogenation to pentanoic acid.
