Propane hydrogenolysis over supported nickel catalysts: Structural and support effects

• Published in: Journal of catalysis Vol. 116; no. 1; pp. 230 - 239
• Main Authors: Burke, P.A., Ko, E.I.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.03.1989; Elsevier
• Subjects: 02 PETROLEUM; 020400 - Petroleum- Processing; ALKANES; Catalysis; CATALYST SUPPORTS; Catalysts: preparations and properties; CATALYTIC EFFECTS; Catalytic reactions; CHALCOGENIDES; CHEMICAL REACTION KINETICS; CHEMICAL REACTIONS; Chemistry; COMPARATIVE EVALUATIONS; DEHYDROGENATION; ELEMENTS; Exact sciences and technology; General and physical chemistry; General. Nomenclature, chemical documentation, computer chemistry; HYDROCARBONS; KINETICS; MATHEMATICAL MODELS; METALS; MINERALS; NICKEL; NIOBIUM COMPOUNDS; NIOBIUM OXIDES; ORGANIC COMPOUNDS; OXIDATION; OXIDE MINERALS; OXIDES; OXYGEN COMPOUNDS; PARTICLE SIZE; PROPANE; REACTION KINETICS; REDUCTION; REFRACTORY METAL COMPOUNDS; REGENERATION; SILICA; SILICON COMPOUNDS; SILICON OXIDES; SIZE; Theory of reactions, general kinetics; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; TITANIUM COMPOUNDS; TITANIUM OXIDES; TRANSITION ELEMENT COMPOUNDS; TRANSITION ELEMENTS; Hydrocarbon; Aliphatic compound; Hydrogenolysis; Catalyst selectivity; Saturated compound; Niobium V Oxides; Experimental study; Silica; Supported catalyst; Surface structure; Titanium «IV» Oxides; Nickel; Kinetics; Catalyst activity; Catalyst support
• ISSN: 0021-9517; 1090-2694
• DOI: 10.1016/0021-9517(89)90088-2

Kinetic data for propane hydrogenolysis were determined for Ni catalysts supported on SiO 2, Nb 2O 5, Nb 2O 5SiO 2, and TiO 2. Over a metal particle size range of 2.5–6.0 nm, the activities for three Ni SiO 2 catalysts varied by no more than a factor of 5. The lowest activity was found for a sample which had been reduced under the most severe conditions and believed to have a large proportion of (111) planes. The sample with the smallest particle size showed a higher selectivity. Activities for Ni supported on the other three oxides were lower, indicative of support effects. For samples reduced at 773 K, the suppression in activity varied in the order Nb 2O 5 > TiO 2 ~ Nb 2O 5 SiO 2. The metal-support interactions were reversible by oxidizing the samples and rereducing at a lower temperature. An oxygen treatment at 473 K was sufficient to recover the activity of Ni TiO 2 but not for Ni Nb 2O 5 , which required an oxygen treatment at 673 K. A model which considers the overall energetics of the regeneration process is presented to explain this difference.