[article]
Titre : |
Synthesis, characterization, and catalytic activity of phosphorus modified H - ZSM - 5 catalysts in selective ethanol dehydration |
Type de document : |
texte imprimé |
Auteurs : |
Kanaparthi Ramesh, Auteur ; Jie Chang, Auteur ; Yi-Fan Han, Auteur |
Année de publication : |
2010 |
Article en page(s) : |
pp. 4080-4090 |
Note générale : |
Industrial chemistry |
Langues : |
Anglais (eng) |
Mots-clés : |
Dehydration Catalyst activity |
Résumé : |
Phosphorus (P) modified H-ZSM-5 catalysts were prepared by wet impregnation method by varying P loadings from 0 to 7.43 wt % using phosphoric acid (H3PO4) as the P source. The catalysts were tested for ethanol dehydration in the temperature range of 523—723 K. The P-modified catalysts were found to be highly active and selective toward ethylene at 673 K and atmospheric pressure. In addition, the P-modified catalysts were found to be extremely stable more than 200 h without any sign of deactivation. However, the selectivity was found to be strongly dependent on several factors such as P content, reaction temperature, and space velocity (WHSV). The P-modified ZSM-5 catalysts were also found to be highly active for the dehydration of aqueous ethanol solutions (10 wt %) showing very high ethylene selectivity (above 98%) at significantly lower temperature 623 K. The catalysts were thoroughly characterized using various methods, including N2 physisorption, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric differential thermal analysis (TG-DTA), 1H, 27Al, and 31P magic angle spinning nuclear magnetic resonance (MAS NMR), and amonia temperature programmed desorption (NH3-TPD). 27Al MAS NMR spectra suggest that P addition facilitate the breaking of Si―O―Al bond that lead to a partial dealumination. NH3-TPD results indicate that total acidity as well as density of high strength acid sites were decreased with P loading. |
ISSN : |
0888-5885 |
En ligne : |
http://cat.inist.fr/?aModele=afficheN&cpsidt=22732897 |
in Industrial & engineering chemistry research > Vol. 49 N° 9 (Mai 2010) . - pp. 4080-4090
[article] Synthesis, characterization, and catalytic activity of phosphorus modified H - ZSM - 5 catalysts in selective ethanol dehydration [texte imprimé] / Kanaparthi Ramesh, Auteur ; Jie Chang, Auteur ; Yi-Fan Han, Auteur . - 2010 . - pp. 4080-4090. Industrial chemistry Langues : Anglais ( eng) in Industrial & engineering chemistry research > Vol. 49 N° 9 (Mai 2010) . - pp. 4080-4090
Mots-clés : |
Dehydration Catalyst activity |
Résumé : |
Phosphorus (P) modified H-ZSM-5 catalysts were prepared by wet impregnation method by varying P loadings from 0 to 7.43 wt % using phosphoric acid (H3PO4) as the P source. The catalysts were tested for ethanol dehydration in the temperature range of 523—723 K. The P-modified catalysts were found to be highly active and selective toward ethylene at 673 K and atmospheric pressure. In addition, the P-modified catalysts were found to be extremely stable more than 200 h without any sign of deactivation. However, the selectivity was found to be strongly dependent on several factors such as P content, reaction temperature, and space velocity (WHSV). The P-modified ZSM-5 catalysts were also found to be highly active for the dehydration of aqueous ethanol solutions (10 wt %) showing very high ethylene selectivity (above 98%) at significantly lower temperature 623 K. The catalysts were thoroughly characterized using various methods, including N2 physisorption, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric differential thermal analysis (TG-DTA), 1H, 27Al, and 31P magic angle spinning nuclear magnetic resonance (MAS NMR), and amonia temperature programmed desorption (NH3-TPD). 27Al MAS NMR spectra suggest that P addition facilitate the breaking of Si―O―Al bond that lead to a partial dealumination. NH3-TPD results indicate that total acidity as well as density of high strength acid sites were decreased with P loading. |
ISSN : |
0888-5885 |
En ligne : |
http://cat.inist.fr/?aModele=afficheN&cpsidt=22732897 |
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