Poisoning of supported platinum catalysts: deactivation by carbon monoxide for methylcyclopropane hydrogenolysis

Thesis/Dissertation · Sun Jan 01 00:00:00 EST 1984

OSTI ID:5513649

Damiani, D E

This study consisted of the characterization of a series of Pt/alumina and Pt/titania catalysts by means of the methylcyclopropane hydrogenolysis under different prepoisoning (progressive poisoning) conditions. The effect of the prepoisoning procedure on Pt/alumina catalysts and the reduction temperature on Pt/titania catalysts was also investigated. The progressive poisoning experiments were done in three different ways: (a) by injection of CO pulses of the fluidized catalytic bed; (b) by partial desorption of a CO monolayer or (c) by injection of pulses of a mixture of hydrogen and CO to the fluidized bed. For Pt/titania catalysts only the first method was used. Poisoning with CO in a pulse mode did not alter the structure sensitivity of the reaction. The apparent activation energy for isobutane (and n-butane) formation slightly increased with increasing poisoning. This charge was associated with the selective deactivation of the sites where the reaction occurs with lower activation energy. Poisoning by partial desorption of preadsorbed CO gave similar results to those mentioned above when poisoning was extensive. For low poisoning levels, a relative higher activity was observed compared to that of similar poison coverage in the pulse mode. Hydrogen and CO coadsorption studies revealed that when the poison and one of the reactants (hydrogen) compete for adsorption sites, the relative strength of their adsorption on the different surfaces is important in determining the deactivation rate (activity as a function of CO coverage).

• Research Organization: Northwestern Univ., Evanston, IL (USA)
• OSTI ID: 5513649
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
CATALYSTS
POISONING
CARBON MONOXIDE
2-METHYLPROPANE
BUTANE
DEACTIVATION
DESORPTION
HYDROGEN
PLATINUM COMPOUNDS
ALKANES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
ELEMENTS
HYDROCARBONS
NONMETALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
080102* - Hydrogen- Production- Thermochemical Processes