Selective hydrogenolysis of glycerol over Ir-Ni bimetallic catalysts

Abstract The effect of the addition of Ni to Ir/γ-Al 2 O 3 was studied for glycerol hydrogenolysis reaction. The catalysts were characterized by textural analysis, XRD, H 2 -TPR, XPS and TEM. In all cases, the addition of Ni to Ir/γ-Al 2 O 3 produced a significant increase in glycerol conversion, and a high selectivity to 1,2-PDO was maintained. TOF values increased from 0.4 × 10 −2  s −1 for Ir monometallic catalyst, to 4.3 × 10 −2  s −1 for bimetallic IrNi 2 _C catalyst. The latter was the most active catalyst among the calcined bimetallic catalysts. Selectivity to 1,2-PDO had an insignificant decrease from 89.9% for Ir monometallic catalyst to 83.1% for IrNi 2 _C catalyst. However, non-calcined IrNi 2 catalyst presented a TOF value of 1.3 × 10 −2  s −1 . This result indicates that the calcination step was fundamental to obtain a strong Ir-Ni interaction that lead to better performances of the bimetallic catalysts. Ir-Ni interaction was evidenced by XPS analyses of the calcined series of catalysts, where the presence of an Ir δ+ species was observed (0