Effect of the metallic particle size of supported Pt catalysts on methylcyclopentane hydrogenolysis: Understanding of the ring opening products distribution by a geometric approach

Description of supported metal structure sensitivity by a geometric approach

“…Description of the model and determination of surface site concentration 3.1.1. Relationship between the crystallite shape, the metallic crystallite size and the parameter m As in our last paper based on the same geometric approach [23], the shape of the Pt crystallites was assumed to be a fcc perfect truncated octahedron (denoted TO, see figure in Table 1). The perfect truncated octahedron is the most common shape admitted in the literature for a crystallized fcc structure of metals like Pt [12,15].…”

“…Knowing the value of the parameter m, it is possible to obtain directly the crystallite size (denoted d in Table 1), or conversely knowing the value of d, it is possible to obtain directly the value of parameter m with the equations given in Table 1 [23]. However, these definitions are true only if the studied particle sizes allow to obtain an integer for the m parameter.…”

“…Based on the works of Van Hardeveld and Hartog [9], we developed a simple model to describe the evolution of the surface structure (corners, edges, faces (100) and faces (111)) for unsupported perfect fcc crystallites with the evolution of the crystallite size, as already described in our reference [23]. Each size is characterized by different atom populations: the total number of atoms (denoted NT), the number of surface atoms (denoted NS), the number of bulk atoms (denoted NB) and the number of atoms with i coordination (denoted NCi and corresponding to the atoms occupying the corners, edges and faces, respectively).…”

Catalytic selective ring opening of polyaromatics for cleaner transportation fuels

“…This 2, entries 7-9), 60,147,148 and only 1% conversion was observed for 1 wt% Pt/Al 2 O 3 (entry 6a). 146 These findings suggest that support effects are negligible when particle sizes are o2 nm. However, for 42 nm Pt particles on alumina (entry 6b) a 20-fold increase in MCP conversion is observed relative on silica (entry 8), evidencing some influence of the support.…”

Etude de la réactivité catalytique du méthylcyclopentane (MCP) sur des catalyseurs oxydes WO3/TiO2et MoO3/TiODjeddi1, Garin2, Fechete3 2020Comptes Rendus. Chimie

“…Le méthylcyclopentane (MCP), de poids moléculaire 84 g•mol −1 , est considéré comme étant une molécule très répandue et utilisée dans le domaine de l'exploitation et de l'investigation des structures des catalyseurs [3][4][5][6][7][8]. Le MCP est très étudié dans les réactions d'ouverture du cycle [9][10][11] et plusieurs catalyseurs ont été utilisés pour l'étude de l'hydrogénolyse du MCP : Ni/Al 2 O 3 [12], Rh/GNF [13], Ge-Rh [14], Rh-Ge/Al 2 O 3 [15], Pd/SAPO-11 [16], Rh/TiO 2 et Rh/SiO 2 [17], Fe-KIT-6 [18], Fe-TUD-1 [19], MnW-MCM-48 [20], CoMn-MCM-48 [21], Co-KIT-6 [22,23].…”