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Effect of oxygen on cyclohexane oxidation / Radmila Jevtic in Industrial & engineering chemistry research, Vol. 48 N° 17 (Septembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 17 (Septembre 2009) . - pp. 7986–7993 Titre : Effect of oxygen on cyclohexane oxidation : a stirred tank study Type de document : texte imprimé Auteurs : Radmila Jevtic, Auteur ; P. A. Ramachandran, Auteur ; Milorad P. Dudukovic, Auteur Année de publication : 2009 Article en page(s) : pp. 7986–7993 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Cyclohexane  oxidation  Nylon-6  Nylon-6,6  Oxygen  availability Résumé : Cyclohexane oxidation is the first step in the currently used technology for production of Nylon-6 and Nylon-6,6 which employs a two-stage process. In the first stage, cyclohexane is oxidized with air to 4−8% conversion at about 80% selectivity to cyclohexanol and cyclohexanone as desired products. In this study, we examined the effect of oxygen availability on the volumetric productivity, yield, and selectivity of this reaction by using a stirred autoclave operated free from mass transfer effects in a batch and “dead-end” semibatch mode. Both uncatalyzed and catalyzed systems were used. The experimental and the modeling results lead to the conclusion that increased oxygen availability improves the productivity and selectivity at the fixed cyclohexane conversion (4%) as the residence time required declines with the increase in oxygen concentration. The positive effect on the reaction rate of increased oxygen concentration is the same when such an increase is achieved at constant pressure by raising the mole fraction of oxygen in the feed or by raising the total pressure in the system at fixed oxygen mole fraction. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900093q [article] Effect of oxygen on cyclohexane oxidation : a stirred tank study [texte imprimé] / Radmila Jevtic, Auteur ; P. A. Ramachandran, Auteur ; Milorad P. Dudukovic, Auteur . - 2009 . - pp. 7986–7993. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 17 (Septembre 2009) . - pp. 7986–7993 Mots-clés : Cyclohexane  oxidation  Nylon-6  Nylon-6,6  Oxygen  availability Résumé : Cyclohexane oxidation is the first step in the currently used technology for production of Nylon-6 and Nylon-6,6 which employs a two-stage process. In the first stage, cyclohexane is oxidized with air to 4−8% conversion at about 80% selectivity to cyclohexanol and cyclohexanone as desired products. In this study, we examined the effect of oxygen availability on the volumetric productivity, yield, and selectivity of this reaction by using a stirred autoclave operated free from mass transfer effects in a batch and “dead-end” semibatch mode. Both uncatalyzed and catalyzed systems were used. The experimental and the modeling results lead to the conclusion that increased oxygen availability improves the productivity and selectivity at the fixed cyclohexane conversion (4%) as the residence time required declines with the increase in oxygen concentration. The positive effect on the reaction rate of increased oxygen concentration is the same when such an increase is achieved at constant pressure by raising the mole fraction of oxygen in the feed or by raising the total pressure in the system at fixed oxygen mole fraction. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900093q