Alumina Supported Iron Catalysts for Selective Acetylene Hydrogenation Under Industrial Front-End Conditions

Abstract

The removal of acetylene traces from ethylene streams coming from the steamcracker is carried out in the industry on an annual scale of several million tons using Pd-Ag/Al₂O₃ catalysts. The substitution of palladium containing catalysts with more abundant, cheap, and nontoxic materials is a first crucial step toward a more sustainable chemical industry. As iron is one of the most abundant metals and can be mined in almost all regions worldwide, it is an ideal catalyst material. In this work, we present the development of α-alumina supported iron catalysts with 1, 5, and 10 wt% iron loading and their application in the selective acetylene hydrogenation under industrially applied front-end conditions. The catalysts were prepared via simple incipient wetness-impregnation and were analyzed via XRD, XRF, TPR, TEM, and N₂-physisorption. The catalysts were subsequently calcined, reduced, and tested in the selective acetylene hydrogenation. After an activation phase, the catalysts show excellent activity and selectivity in the acetylene hydrogenation at 90 °C without significant ethylene hydrogenation. The excellent catalytic activity underline the great potential of iron based catalysts as an alternative to conventional Pd-containing materials.