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Hydrogenation of dimethyl-nitrobenzene to dimethyl-aniline in a three-phase Reactor

Mansoor Kazemimoghadam


The liquid-phase catalytic hydrogenation of dimethyl-nitrobenzene (DN) to Dimethyl-aniline (DA) was carried out in ethanol using 5% Pd/C as a catalyst. The effects of hydrogen partial pressure (400–1000 kPa), reaction temperature (343–403 ), catalyst loading (5–15 g/lit), speed of stirring range (200-800 rpm) and dimethyl-nitrobenzene concentration (0.12–0.75 mol/lit) on the hydrogenation of dimethyl-nitrobenzene and the yield of Dimethyl-aniline have been studied. Dimethyl-aniline was the only reaction product, generated through the hydrogenation of the Nitro group of dimethyl-nitrobenzene. The effects of hydrogen partial pressure, catalyst loading, dimethyl-nitrobenzene concentration and temperature on the reaction conversion have been reported. Near first-order dependence on dimethyl-nitrobenzene concentration and hydrogen pressure were observed for the initial rate of dimethyl-nitrobenzene hydrogenation over the 5% Pd/C catalyst. Conventional Arrhenius behavior was exhibited by catalyst, Pd/C showed activation energies of 614 J/mol. A simple power law model was used for analysis of the reaction kinetic data.

Keywords: Liquid-phase hydrogenation; Pd/C catalysts; dimethyl-nitrobenzene; dimethyl-aniline; operation condition

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P. Reyes, H. Rojas, J.L.G. Fierro, Kinetic study of liquid-phase hydrogenation of citral over Ir/TiO2 catalysts, Applied Catalysis A: General 248 (2003) 59–65.

P. Haldar, V.V. Mahajani, Catalytic transfer hydrogenation: o-nitro anisole to o-anisidine, some process development aspects, Chemical Engineering Journal 104 (2004) 27–33.

Dilip R.Patel, R.N. Ram, Hydrogenation of nitrobenzene using polymer anchored Pd (II) complexes, Journal of Molecular Catalysis A: Chemical 130 (1998) 57-64.

Volker Holler, Dagmar Wegricht, Igor Yuranov, Lioubov Kiwi-Minsker, and Albert Renken, Three-Phase Nitrobenzene Hydrogenation over Supported Glass Fiber Catalysts: Reaction Kinetics Study, Chem. Eng. Technol. 23 (2000) 3.

Nivedita S. Chaubal, Manohar R. Sawant, Nitro compounds reduction via hydride transfer using mesoporous mixed oxide catalyst, Journal of Molecular Catalysis A: Chemical 261 (2006) 232–241

Shao-Pai Lee, Yu-Wen Chen, Nitrobenzene hydrogenation on Ni–P, Ni–B and Ni–P–B ultrafine materials, Journal of Molecular Catalysis A: Chemical 152 _2000. 213–223.

Sunil P. Bawane, Sudhirprakash B. Sawant, Hydrogenation of p-nitrophenol to metol using Raney nickel catalyst: Reaction kinetics, Applied Catalysis A: General 293 (2005) 162–170.

Sunil K. Maity, Narayan C. Pradhan, Anand V. Patwardhan, Kinetics of the reduction of nitrotoluenes by aqueous ammonium sulfide under liquid–liquid phase transfer catalysis, Applied Catalysis A: General 301 (2006) 251–258

Prakash D. Vaidya, Vijaykumar V. Mahajani, Kinetics of liquid-phase hydrogenation of n-valeraldehyde to n-amyl alcohol over a Ru/Al2O3 catalyst, Chemical Engineering Science 60 (2005) 1881 – 1887.

T. Swathi, G. Buvaneswari, Application of NiCo2O4 as a catalyst in the conversion of p-nitrophenol to p-aminophenol, Materials Letters 62 (2008) 3900–3902.

Leanne McLaughlin, Ekaterina Novakova, Robbie Burch, Christopher Hardacre, Hydrogenation/hydrogenolysis of disulfides using sulfided Ni/Mo catalysts, Applied Catalysis A: General 340 (2008) 162–168.

Sachin U. Sonavane, Manoj B. Gawande, Sameer S. Deshpande, A. Venkataraman, Radha V. Jayaram, Chemo selective transfer hydrogenation reactions over nanosized c-Fe2O3 catalyst prepared by novel combustion route, Catalysis Communications 8 (2007) 1803–1806

Jia-Huei Shen, Yu-Wen Chen, Catalytic properties of bimetallic NiCoB nano alloy catalysts for hydrogenation of p-chloronitrobenzene, Journal of Molecular Catalysis A: Chemical 273 (2007) 265–276.

Tatiana Tehila Bovkun, Michael Grayevsky, Yoel Sasson, Jochanan Blum, Liquid phase hydrogenation and hydrodenitrogenation of aromatic nitrogen-containing environmental pollutants, Journal of Molecular Catalysis A: Chemical 270 (2007) 171–176

Ekaterina K. Novakova, Leanne McLaughlin, Robbie Burch, Paul Crawford, Ken Griffin, Christopher Hardacre, Peijun Hu, David W. Rooney, Palladium-catalyzed liquid-phase hydrogenation/hydrogenolysis of disulfides, Journal of Catalysis 249 (2007) 93–101.

Yu-Zhi Haoa, Zuo-Xi Li, Jin-Lei Tian, Synthesis, characteristics and catalytic activity of water-soluble [Pd(lysine·HCl)(Cl)2] complex as hydrogenation catalyst, Journal of Molecular catalysis A: Chemical 265 (2007) 258–267.

Christopher M. Vogels, Andreas Decken and Stephen A. Westcott, Catalyzed hydroboration of nitrostyrenes and 4-vinylaniline: a mild and selective route to aniline derivatives containing boronate esters, Tetrahedron Letters 47 (2006) 2419–2422.

Qiong Xua, Xin-Mei Liu, Jun-Ru Chen, Rui-Xiang Li, Xian-Jun Li, Modification mechanism of Sn4+ for hydrogenation of p-chloronitrobenzene over PVP-Pd/Al2O3, Journal of Molecular Catalysis A: Chemical 260 (2006) 299–305

Atsushi Akao, Kimihiko Sato, Nobuaki Nonoyama, Toshiaki Masea and Nobuyoshi Yasud, Highly chemo selective reduction using an Rh/C–Fe (OAc) 2 system: practical synthesis of functionalized indoles, Tetrahedron Letters 47 (2006) 969–972.


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