Documents disponibles écrits par cet auteur

Hydrogenation of nitrobenzene to aniline over silica gel supported nickel catalysts / Junhua Wang in Industrial & engineering chemistry research, Vol. 49 N° 10 (Mai 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4664–4669 Titre : Hydrogenation of nitrobenzene to aniline over silica gel supported nickel catalysts Type de document : texte imprimé Auteurs : Junhua Wang, Auteur ; Zhenle Yuan, Auteur ; Renfeng Nie, Auteur Année de publication : 2010 Article en page(s) : pp. 4664–4669 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Silica  gel  Catalysts Résumé : Nanosized silica gel supported Ni catalysts that have average Ni particle size of 3.7, 11.4, and 11.8 nm were prepared by facile impregnation of different Ni precursors and used for hydrogenation of nitrobenzene (NB). These catalysts were characterized by N2 adsorption, X-ray diffraction, and transmission electron microscopy. It was found that Ni dispersed highly on the surface of silica gel in the catalyst prepared via Ni(en)3(NO3)2, and the detected average Ni particle size was 3.7 nm. On the 3.7 nm sized Ni catalyst, the selectivity of aniline (AN) reached 99% with a 100% conversion of NB in 5.5 h at 90 °C, 1.0 MPa, and NB:Ni = 305 (mole ratio). But, the activities of 11.8 nm sized Ni catalysts and commercial Raney Ni catalyst are quite lower. The reaction network and mechanism of NB hydrogenation on 3.7 nm sized Ni catalyst were discussed on the basis of products distributions at different temperatures and pressures. The calculated activation energy of NB hydrogenation on Ni-5/SiO2-EN catalyst is 54.5 kJ/mol in 70−90 °C. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1002069 [article] Hydrogenation of nitrobenzene to aniline over silica gel supported nickel catalysts [texte imprimé] / Junhua Wang, Auteur ; Zhenle Yuan, Auteur ; Renfeng Nie, Auteur . - 2010 . - pp. 4664–4669. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4664–4669 Mots-clés : Silica  gel  Catalysts Résumé : Nanosized silica gel supported Ni catalysts that have average Ni particle size of 3.7, 11.4, and 11.8 nm were prepared by facile impregnation of different Ni precursors and used for hydrogenation of nitrobenzene (NB). These catalysts were characterized by N2 adsorption, X-ray diffraction, and transmission electron microscopy. It was found that Ni dispersed highly on the surface of silica gel in the catalyst prepared via Ni(en)3(NO3)2, and the detected average Ni particle size was 3.7 nm. On the 3.7 nm sized Ni catalyst, the selectivity of aniline (AN) reached 99% with a 100% conversion of NB in 5.5 h at 90 °C, 1.0 MPa, and NB:Ni = 305 (mole ratio). But, the activities of 11.8 nm sized Ni catalysts and commercial Raney Ni catalyst are quite lower. The reaction network and mechanism of NB hydrogenation on 3.7 nm sized Ni catalyst were discussed on the basis of products distributions at different temperatures and pressures. The calculated activation energy of NB hydrogenation on Ni-5/SiO2-EN catalyst is 54.5 kJ/mol in 70−90 °C. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1002069