Low-temperature partial oxidation of methane over Pd-Ni bimetallic catalysts supported on CeO2

Monometallic Pd and Ni and bimetallic Pd-Ni catalysts supported on CeO2 are prepared via mechanochemical and conventional incipient wetness impregnation methods and tested for the production of syngas by the partial oxidation of methane. Compared with monometallic Ni/CeO2 and Pd/CeO2, bimetallic Pd-Ni/CeO2 catalysts show considerable higher methane conversion and syngas yield. Additionally, the bimetallic catalysts prepared by ball milling produce syngas at lower temperature. Different preparation parameters, such as metal loading, Pd/Ni ratio, milling energy, milling time and order of incorporation of the metals are examined. The best performance is obtained with a bimetallic catalyst prepared at 50 Hz for 20 min with only 0.12 wt% Pd and 1.38 wt% Ni. Stability tests demonstrate superior stability for bimetallic Pd-Ni/CeO2 catalysts prepared by a mechanochemical approach. From the characterization results, this is explained in terms of an impressive dispersion of metal species with a strong interaction with the surface of CeO2.(c) 2022 The Author(s). Published by Elsevier Ltd on behalf of Hydrogen Energy Publications creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

Monometallic Pd and Ni and bimetallic Pd-Ni catalysts supported on CeO2 were prepared and tested for syngas production by the partial oxidation of methane. Bimetallic Pd-Ni/CeO2 catalysts exhibited higher methane conversion and syngas yield compared to monometallic Ni/CeO2 and Pd/CeO2. The bimetallic catalysts prepared by ball milling showed syngas production at lower temperatures. Various preparation parameters were examined, and the best performance was achieved with a bimetallic catalyst prepared at 50 Hz for 20 min, containing only 0.12 wt% Pd and 1.38 wt% Ni. Stability tests demonstrated superior stability for mechanochemically prepared bimetallic Pd-Ni/CeO2 catalysts. The results suggest that the impressive dispersion of metal species and strong interaction with the CeO2 surface contribute to the improved performance.