Phosphorus-modification of supported transition metal catalysts

Hydrogenation and dehydrogenation reactions will play an important role in the future hydrogen economy, requiring highly active and robust catalytic materials. Phosphorus-modification of supported transition metal catalysts is a powerful tool to tailor catalyst properties such as metal dispersion, activity and selectivity and has shown in the past to have beneficial electronic and steric effects on the catalytic metal.^1,2

Modification of alumina-supported Pt-catalysts with phosphorus boosts the activity in the dehydrogenation of cycloalkanes, such as perhydro benzyltoluene. The P-modification can occur via classical impregnation or also via a solvent-free step using an in-situ formed gaseous P-precursor. The phosphorus species on the catalyst surface enhances and stabilizes the Pt-dispersion (up to 900 °C) and exerts an additional electronic effect resulting in enhanced dehydrogenation activities.

Carrying on with the abovementioned work, this concept is advanced towards other catalyst systems. For instance, P-modification of Pd/Al₂O₃ shows promising results in hydrogenation reactions. In this project we further evaluate the effect of P-modification on the resistance against possible impurities in hydrogenation with impure hydrogen.

The potential of tailoring properties such as dispersion, stability and selectivity makes P-modified supported transition metal catalysts promising materials in the field of (de-)hydrogenation and high temperature applications.

(1)       Stöber, R.; Mai, F.; Sebastian, O.; Körner, A.; Hutzler, A.; Schühle, P. A Highly Stable Bimetallic Transition Metal Phosphide Catalyst for Selective Dehydrogenation of N‐ Heptane. ChemCatChem 2022, 14 (18). https://doi.org/10.1002/cctc.202200371.

(2)       Ellert, A.; Herold, F.; Rønning, M.; Hutzler, A.; Piccirilli, L.; Janssens, T. V. W.; Vennestrøm, P. N. R.; Wasserscheid, P.; Schühle, P. Phosphorus-Modification of Pt/Al2O3 Catalysts Improves Dispersion and Cycloalkane Dehydrogenation Activity. Journal of Catalysis 2024, 436, 115607. https://doi.org/10.1016/j.jcat.2024.115607.