The present work describes the preparation of p-aminophenol via single-step catalytic hydrogenation of nitrobenzene in acid medium. A conventional method of synthesis of p-aminophenol is a two-step reaction involving iron-acid reduction of pnitrophenol. This method causes serious effluent disposal problems due to the stoichiometric use of iron-acid, which leads to the formation of Fe-FeO sludge (=1.2 kg/kg of product) in the process, which cannot be recycled. The single-step hydrogenation of nitrobenzene was carried out using platinum catalyst, and the process conditions were optimized. Complete conversion of nitrobenzene was achieved with selectivity to p-aminophenol as high as 75% under the best set of conditions. Furthermore, the catalyst can be easily recovered and efficiently recycled giving the TON as high as 1.38 × 10. 5 This paper presents studies on the effect of various process parameters such as temperature, hydrogen pressure, and substrate and acid concentration on the rate of reaction and selectivity to paminophenol.

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Various iridium supported carbon catalysts were prepared and screened for the direct hydrogenation of furfural (FFR) to 2-methyl furan (2-MF).

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