화학공학소재연구정보센터
Journal of Molecular Catalysis A-Chemical, Vol.273, No.1-2, 160-168, 2007
Selective hydrogenation of bromonitrobenzenes over Pt/gamma-Fe2O3
The Pt/gamma-Fe2O3 nanocomposite catalyst exhibited high catalytic activities and superior selectivities to ortho-bromoaniline (o-BAN), meta-bromoaniline (m-BAN) and para-bromoaniline (p-BAN) in the hydrogenation of ortho-bromonitrobenzene (o-BNB), meta-bromonitrobenzene (m-BNB) and para-bromonitrobenzene (p-BNB), respectively. The hydrodebromination of bromoanilines (BANs) over the Pt/gamma-Fe2O3 nanocomposite catalyst was fully suppressed even at complete conversion of the substrates for the first time. Elevating hydrogen pressure from 0.1 to 2.0 MPa could not only increase the hydrogenation rates of o-BNB, m-BNB and p-BNB by 8.8, 11.8 and 10.0 times, respectively, but also further improve the selectivities to o-BAN, m-BAN and p-BAN to a level higher than 99.9%. A new hydrodebromination pathway in the hydrogenation of bromonitrobenzenes (BNBs), i.e. through the hydrodebromination of the condensation intermediates was revealed. (C) 2007 Elsevier B.V. All rights reserved.