On the origin of the high performance of MWNT-supported PtPd catalysts for the hydrogenation of aromatics

Enhancement of naphthalene hydrogenation over PtPd/SiO2–Al2O3 catalyst modified by gold

“…In keeping with the foregoing, this paper extends our previous investigation on the use of MWNT [33] and amorphous ASA [7,14,17] as supports and Au as promoter of Pt-and Pd-based catalysts [14][15][16][17][18] with the aim to investigate the hydrogenation behavior of ternary AuPtPd formulation in comparison with binary PtPd systems. The hydrogenation activities of catalysts were compared in naphthalene hydrogenation whereas thio-resistance of ternary sample was confirmed during simultaneous naphthalene and toluene hydrogenation in the presence of dibenzothiophene (DBT; 100 ppm of S).…”

“…Before catalyst preparation, the MWNT was treated with HNO 3 (concentration 65%) at 383 K for 12 h in order to introduce -OH groups onto carrier, which are necessary to anchor the metal precursors on the surface. In a previous work [33], it was shown HNO 3 -functionalization of MWNT develops strong acidic groups (carboxylic anhydride, carboxylic, lactone) and also increases the population of less acidic groups (anhydride, phenol, ether, carbonyl, quinine) by a factor of about 4.…”

“…Among the possible less acidic carriers, one-dimensional multi-walled carbon nanotubes (MWNT) are interesting candidates because of their large mesoand macroporous structure [25]. Carbon nanotubes (CNT) and fibers as supports have been already applied for reactions involving hydrogen [26][27][28][29][30][31][32][33]. Indeed, our recent study on PtPd/MWNT catalyst tested in simultaneous toluene and naphthalene HYD in the presence of DBT demonstrated its exceptionally high initial intrinsic hydrogenation activity [33].…”

High Activity in Catalytic Oxidation of Benzyl Alcohol with Molecular Oxygen over Carboxylic-Functionalized Carbon Nanofiber-Supported Ruthenium Catalysts

“…Carbon nanofibers (CNF) and carbon nanotubes (CNT) as catalyst supports have been widely used in light alkenes hydrogenation [1][2][3][4][5], a,b-unsaturated aldehydes hydrogenation [6][7][8][9][10][11][12][13][14][15][16][17][18], nitrobenzene hydrogenation [19][20][21], cyclohexene hydrogenation [22], alkene hydroformylation [6,23], ammonia synthesis [24,25], cyclohexanol dehydrogenation [26,27], Fischer-Tropsch synthesis [28][29][30][31], decomposition of NO [32], n-hexane isomerization [33], aromatic hydrogenation [34,35], and aniline oxidation [36,37]. Compared with the conventional catalyst supports such as activated carbon, c-Al 2 O 3 , and SiO 2 , CNF, and CNT supports have obvious features such as graphitic nature and high capability of hydrogen storage, which are favorable for the metal-support interaction [2, 8-12, 32, 37], the electron transfer between support and metallic particles [2,24,25], and the formation of surface hydrogen atoms on the active sites [33].…”

Catalytic enhancement of platinum supported on zeolite beta for toluene hydrogenation by addition of palladium

“…Metal particle sizes were calculated from the line broadening of the metal peak with highest intensity using the Scherrer equation [15] as shown in Eq. (1).…”