1. LIQUID-PHASE HYDROGENATION OF m-DINITROBENZENE OVER PLATINUM CATALYSTS
- Author
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Jesús S. Valencia, Patricio Reyes, Hugo Rojas, María H. Brijaldo, and Gloria Borda
- Subjects
Materials science ,Physisorption ,Hydrogen ,chemistry ,Chemisorption ,Thermal desorption spectroscopy ,Inorganic chemistry ,chemistry.chemical_element ,General Chemistry ,Crystallite ,Temperature-programmed reduction ,Platinum ,Catalysis - Abstract
The m-dinitrobenzene hydrogenation to m-phenylenediamine in liquid phase was studied with platinum supported on SiO 2 , TiO 2 , Al 2 O 3 and Nb 2 O 5 catalysts. Incipient impregnation method was used to prepare the catalysts with 1wt% of Pt. The effect of the support and the reduction temperature (473 K or 773 K) were analyzed. The materials were characterized by X-ray diffraction (XRD), nitrogen physisorption (77 K), hydrogen chemisorption (298 K), transmission electron microscopy (TEM), temperature programmed reduction (H 2 -TPR) and temperature programmed desorption of ammonia (NH 3 -TPD). The results showed that Pt/ TiO 2 (HT) catalyst had a higher yield (60%) toward m- phenylenediamine and conversion level (98.2%) of m-dinitrobenzene. This behavior can be attributed to the reduction of PtO x crystallites to metallic Pt, small particle size and the strong metal-support interaction due to the migration of TiO x species on the Pt crystallites.
- Published
- 2011