Palladium phosphide nanoparticles as highly selective catalysts for the selective hydrogenation of acetylene

• Published in: Journal of catalysis 2018-08, Vol.364 (C), p.406-414
• Main Authors: Liu, Yanan, McCue, Alan J., Miao, Chenglin, Feng, Junting, Li, Dianqing, Anderson, James A.
• Format: Article
• Language: English
• Subjects: Acetylene; Alkyne; Ethylene; Palladium phosphide; Selective hydrogenation; Site-isolation
• ISSN: 0021-9517; 1090-2694
• DOI: 10.1016/j.jcat.2018.06.001

[Display omitted] •TiO2 supported Pd3P and PdP2 phases with similar particle size were fabricated.•PdP2 phase is more selective than Pd3P for acetylene hydrogenation.•PdP2/TiO2 is highly selective (84%) at full conversion for acetylene hydrogenation.•Enhanced selectivity of PdP2/TiO2 is attributed to increased Pd site isolation.•Stable long-term selectivity observed for PdP2/TiO2 formulation. Pd3P and PdP2 phases of ca. 4 nm particle diameter were prepared on a TiO2 support by an impregnation route. Data from the hydrogenation of acetylene under both non-competitive and competitive conditions showed that PdP2/TiO2 exhibits enhanced selectivity and stability relative to Pd3P. Furthermore, the selectivity produced over PdP2 (84% ethylene selectivity @ 100% acetylene conversion) compares favorably with recently reported materials. XPS and CO-IR measurements reveal that the incorporation of P helps to break up contiguous Pd sites. This in turn is thought to affect the adsorption and desorption of reactants/products and thus improves selectivity. This work reveals that the incorporation of P into Pd materials could be regarded as a promising approach to develop new and improved Pd-based catalyst by creating a means to control the nature of the active sites.