Details

Autor(en) / Beteiligte

• Min, Kyung-Il
• Choi, Jung-Sik
• Chung, Young-Min
• Ahn, Wha-Seung
• Ryoo, Ryong
• Lim, P.K.

Titel

p-Aminophenol synthesis in an organic/aqueous system using Pt supported on mesoporous carbons

Ist Teil von

• Applied catalysis. A, General, 2008-03, Vol.337 (1), p.97-104

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

2008

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The biphasic conversion of nitrobenzene to p-aminophenol (PAP) via Pt/C-catalyzed hydrogenation of nitrobenzene and an acid-catalyzed rearrangement of the N-phenylhydroxylamine intermediate was studied. The effects of Pt/C catalyst loading, type of carbon support, reaction temperature, acid catalyst concentration, and additives were investigated. Pt catalysts supported on novel mesoporous carbons which have uniform pore diameters of 3 and 4.5 nm significantly outperform their counterpart supported on activated carbon. ▪ The biphasic conversion of nitrobenzene to p-aminophenol (PAP) via Pt/C-catalyzed hydrogenation of nitrobenzene and an acid-catalyzed rearrangement of the N-phenylhydroxylamine intermediate was studied. The effects of Pt/C catalyst loading, type of carbon support, reaction temperature, acid catalyst concentration, and additives on the reaction rate and PAP selectivity were investigated. At a given catalyst loading, nitrobenzene conversion and PAP selectivity were favored under a high reaction temperature and a high aqueous acid concentration. An increase in Pt/C catalyst loading leads to an increased hydrogenation rate but a lower PAP selectivity. Nitrobenzene conversion and PAP selectivity are both promoted by a small addition of N, N-dimethyl- n-dodecylamine, which may act as a phase transfer agent or emulsifier. Pt catalysts supported on novel mesoporous carbons – CMK-1 and CMK-3, which have uniform pore diameters of 3 and 4.5 nm – significantly outperform their counterpart supported on activated carbon with micropores. Two percent Pt/CMK-1 shows a catalytic activity equivalent to that of 5% Pt/C, but with significantly better PAP selectivity, i.e., 84% compared to 72%.