Synthesis and Hydrodesulfurization Properties of Noble Metal Phosphides: Ruthenium and Palladium

Autor: Bo A. Carrillo, Richard H. Bowker, Mark E. Bussell, Mica C. Smith
Rok vydání: 2012
Předmět:
Zdroj: Topics in Catalysis. 55:999-1009
ISSN: 1572-9028
1022-5528
DOI: 10.1007/s11244-012-9887-y
Popis: Silica-supported ruthenium and palladium phosphide catalysts (Ru2P, RuP, Pd3P, Pd5P2) were investigated for the hydrodesulfurization (HDS) of dibenzothiophene (DBT). The Ru and Pd phosphide catalysts were prepared by temperature-programmed reduction of hypophosphite-based precursors consisting of uncalcined or calcined Ru/SiO2 or Pd/SiO2 impregnated with ammonium hyposphosphite (NH4H2PO2). The Ru2P/SiO2 and RuP/SiO2 catalysts prepared from uncalcined precursors had smaller average crystallite sizes, higher CO chemisorption capacities, and higher HDS activities than the catalysts prepared from the calcined precursors, while the effect of preparation method on catalytic properties was less clear for the Pd3P/SiO2 and Pd5P2/SiO2 catalysts. Following HDS testing at 673 K, X-ray diffraction analysis revealed that the Pd5P2/SiO2 catalysts decomposed to give Pd3P on the silica support, while the other phosphides exhibited good stability during the testing period. At temperatures at which high DBT conversion was observed (>598 K), the Ru and Pd phosphide catalysts were less active than sulfided Ru/SiO2 and Pd/SiO2 catalysts prepared from the uncalcined metal precursors.
Databáze: OpenAIRE