An examination of catalyst deactivation in p-chloronitrobenzene hydrogenation over supported gold

In situ synthesis of nickel carbide-promoted nickel/carbon nanofibers nanocomposite catalysts for catalytic applications

“…Many 3 efforts have been devoted to performing the hydrogenation of halogenated nitro compounds over a variety of supported noble metals (e.g. Ag, Au, Pd, Pt and Ru) [24][25][26][27][28][29][30][31][32][33][34]. In addition to their high cost in industrial applications, the problem often arising is that highly active noble metals are not selective toward haloanilines and must be modified by alloying or poisoning with other metal oxides or the application of several promoters [23,35,36], but in most cases at the expenses of catalytic activity.…”

Carbon supported gold and silver: Application in the gas phase hydrogenation of m -dinitrobenzene

“…6). In contrast, temporal deactivation in hydrogenation over oxide supported Au [29,[66][67][68][69] and Ag [70] has been reported and attributed to coke formation [29,66], metal sintering [67,70] and reactant poisoning of active sites [68,69]. Given the higher conversions achieved we focused our attention on a comparison of 0.1%wt.…”

“…Catalyst activation by temperature programmed reduction (TPR) employed a 2 K min −1 ramp to 623 K in 60 cm 3 min −1 H 2 . The temperature requirements for reduction of supported Au and Ag precursors have been discussed elsewhere [7,29]. Post-activation the samples were cooled to ambient temperature and passivated in 1% v/v O 2 /He for 1 h for ex situ characterisation.…”

Structure‐Activity Relationships of Au/Al2O3 Catalyst for the Selective Oxidative Esterification of 1,3‐Propanediol and Methanol

“…As compared with bulk gold, The downward shifts of Au 4 f in these catalysts suggest a modification of the electronic states of Au due to interactions between the gold nanoparticles and the supports . A similar negative shift in binding energy for Au on γ‐Al 2 O 3 (Au 4f 7/2 =83.4 eV) have also been reported, which was attributed to electron transfer from the support . The sample of 1.5 wt.…”