کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
61909 | 47612 | 2011 | 12 صفحه PDF | دانلود رایگان |
The influence of PtRu bimetallic particle size and composition on cinnamaldehyde selective hydrogenation has been investigated for the first time using well-defined catalysts based on carbon nanotubes support. Very high selectivity towards cinnamyl alcohol together with high activity have been obtained provided a high temperature treatment of the catalyst is performed. HRTEM, WAXS and EXAFS analyses permit us to conclude that the remarkable influence of this high temperature treatment on both activity and selectivity arises from different phenomena. First, a particle size and a structural effect have been evidence that permits to increase the selectivity. WAXS and EXAFS point the formation of alloyed PtRu nanoparticles. Second, the heat treatment allows the removal of oxygenated groups from CNT surface. This may increase the cinnamaldehyde adsorption capacity and decrease the activation barrier for diffusion of substrate and product on the CNT surface, thus contributing to an increase in the activity.
Very active and selective Pt–Ru/CNT catalysts have been prepared for the selective hydrogenation of cinnamaldehyde into cinnamyl alcohol. Characterization using HRTEM, WAXS and EXAFS was indicative of the influence of particles alloying on the selectivity of these systems..Figure optionsDownload high-quality image (179 K)Download as PowerPoint slideResearch highlights
► We produced well-dispersed bimetallic PtRu catalysts on carbon nanotubes.
► We discovered a selective catalytic system for the selective hydrogenation of cinnamaldehyde.
► We investigated the structure–activity correlation of this new PtRu catalyst.
► We demonstrated the role of the activation by thermal treatment.
Journal: Journal of Catalysis - Volume 278, Issue 1, 14 February 2011, Pages 59–70