Preparation of Pd/AC Catalyst by Ion Exchange
Résumé
By choosing appropriate liquid oxidizing treatment, the carbonaceous surface of an activated carbon (AC) can be functionalised with carboxylic groups in a broad range of content. These carboxylic groups are necessary functions, in order to disperse, perfectly, palladium cations through exchange reactions: H+/Pd2+ or H+/Pd(OH)+. Reduction in liquid phase of a 4 mass %Pd/AC whose carbonaceous surface was previously oxidized by NaOCl leads to palladium particles with a particle size of 1.5 nm which are much smaller than Pd particles obtained from a 4 mass % Pd/AC whose carbon surface was not oxidized. The well dispersed catalyst was tested in hydrogenation of cinnamaldehyde and exhibits quite a high hydrogenation efficiency as compared to activities reported in the literature.