Abstract
The kinetics of liquid-phase hydrogenation of dimethyl-nitrobenzene (DN) on 5% Pd/C catalysts were studied in the temperature range of 343–403*K and a pressure range of 4–10 bar H2, using ethanol as the solvent. Dimethyl-aniline (DA) 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. Furthermore, an increase in the catalytic activity as the reaction temperature, pressure and weight of catalysts was observed. 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.
Key-Words / Index Term
Liquid-phase hydrogenation; Pd/C catalysts; dimethyl-nitrobenzene; dimethyl-aniline; kinetic
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