An analysis of electroless deposition derived Ni-Pt catalysts for the dry reforming of methane

• Published in: Journal of catalysis 2020-01, Vol.381, p.374-384
• Main Authors: Egelske, Benjamin T., Keels, Jayson M., Monnier, John R., Regalbuto, John R.
• Format: Article
• Language: English
• Subjects: Compensation effect; Dry reforming; Electroless deposition; Kinetics; Nickel-platinum
• ISSN: 0021-9517; 1090-2694
• DOI: 10.1016/j.jcat.2019.10.035

[Display omitted] •The promotion of Ni by small amounts of Pt for DRM has been demonstrated at T ≤ 600 °C.•Using electroless deposition of Pt onto Ni, bimetallic interaction is maximized.•At 700 °C or above, the promotional effect is lost as the Pt and Ni phases separate.•Extended runtimes yield accurate measurement of catalyst stability and performance. A series of nickel-platinum catalysts supported on gamma alumina (γ-Al2O3) with small, increasing amounts of Pt promoter were precisely prepared by electroless deposition at 5.0 wt% Ni and with compositions up to 2.8 wt% Pt (one theoretical monolayer of Pt on Ni) and evaluated for the dry reforming of methane. Characterization was performed using x-ray diffraction, temperature programmed reduction, scanning transmission electron microscopy, and temperature programmed oxidation. At temperatures below 600 °C, activity of bimetallic samples exhibited a maximum at 0.4 monolayers Pt and surpassed that of unpromoted Ni. At 700 °C, deactivation occurred for all samples. X-ray diffraction patterns of the high-temperature treated catalysts indicated segregation of the Ni-Pt alloys. Pt showed no influence on hydrogen selectivity, which was driven by thermodynamic limits.