In Situ DRIFTS Investigation During the Adsorption of 1-Pentyne and Catalytic Performance of Pd-Ni Bimetallic Catalysts for Olefinic Purification

In this work, the impregnation order of the second metal and the catalytic performance of low loaded Pd and Ni bimetallic catalysts were studied using different supports (gamma-Al2O3, gamma-Al2O3-Mg, CaCO3 and RX3). These catalysts were assessed in the selective hydrogenation of 1-pentyne and the purification of a mixture of 1-pentene/1-pentyne 70/30 vol%. The results showed that the synthesized catalysts were active and very selective (>= 85%) for obtaining the desired product (1-pentene). Different adsorbed species (-C equivalent to C- and -C=C-) were observed on the bimetallic surface using in situ DRIFT analysis, which can be responsible of the high selectivity reached. The order of impregnation of the metals modifies the electronic and geometric properties of the synthesized catalysts. The best catalytic performance was obtained when the Pd is impregnated in second place: Ni-Pd/Support. The results show that the synthesized bimetallic catalysts have favorable properties and are promising for olefin purification reactions.

Automated summary

In this study, the impregnation order of metals on different supports was found to affect the catalytic performance of low loaded Pd and Ni bimetallic catalysts. The synthesized catalysts exhibited high activity and selectivity in selective hydrogenation and purification reactions, and the order of metal impregnation played a role in modifying the catalysts' properties. The observation of different adsorbed species on the bimetallic surface during the reaction was important for achieving high selectivity.