Effect of Addition Mode of Re in Bimetallic Pd–Re/TiO2 Catalysts Upon the Selective Aqueous-Phase Hydrogenation of Succinic Acid to 1,4-Butanediol
Résumé
Hydrogenation of succinic acid aqueous solutions was performed using TiO2-supported 2 wt% Pd and 2 wt%Pd–x wt%Re catalysts, using either impregnation method or surface redox reduction of the monometallic catalyst. The former catalysts were superior in terms of activity and selectivity to 1,4-butanediol than the latter ones. However, higher Re loadings (3.4–3.6 wt% compared to 0.6–0.8 wt%) were necessary to initiate this synergy.