Fabrication of stable and selective non-noble metal catalysts for selective alkyne hydrogenation

Modification of Ni/Al2O3 catalysts with Sn is appealing for tuning catalyst activity and selectivity for hydrogenation reactions. However, a strong interaction between the Al2O3 and Sn ions can lead to problems when a traditional impregnation strategy is employed. For example, tin aluminate complexes can form and uneven distribution of the metals can occur. In this work, a support coordination induction strategy is developed, in which the use of a rod-shaped Al2O3 with a high number penta-coordinated Al3+ surface species prepared from a rotating liquid film reactor was used. The unsaturated Al3+ coordination sites on this support induce the formation of a stable and uniform Ni-Sn intermetallic phase without the appearance of either monometallic Ni or SnO2 particles. This uniform Ni-Sn intermetallic phase was then shown to be responsible for enhanced activity, selectivity, and stability for alkyne hydrogenation relative to samples which lacked the same level of Ni-Sn uniformity.