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Oxygenated biofuels from butanol for diesel blends: synthesis of the acetal 1,1-dibutoxyethane catalyzed by amberlyst-15 Ion-exchange resin / Nuno S. Graça in Industrial & engineering chemistry research, Vol. 49 N° 15 (Août 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 15 (Août 2010) . - pp 6763–6771 Titre : Oxygenated biofuels from butanol for diesel blends: synthesis of the acetal 1,1-dibutoxyethane catalyzed by amberlyst-15 Ion-exchange resin Type de document : texte imprimé Auteurs : Nuno S. Graça, Auteur ; Luis S. Pais, Auteur ; Viviana M. T. M. Silva, Auteur Année de publication : 2010 Article en page(s) : pp 6763–6771 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Biofuels  butanol  Dibutoxyethane. Résumé : The synthesis of 1,1-dibutoxyethane or acetaldehyde dibutylacetal was studied in a batch reactor by reacting butanol and acetaldehyde in a liquid phase, using Amberlyst-15 as the catalyst. The reaction equilibrium constant was experimentally determined in the temperature range 20−40 °C at 6 atm, where Ka = 0.00959 exp[1755.3/T (K)]. The standard properties of the reaction at 298.15 K were estimated: ΔH° = −14.59 kJ mol−1, ΔG° = −3.07 kJ mol−1, and ΔS° = −38.64 J mol−1 K−1. Kinetic experiments were performed in the temperature range 10−50 °C at 6 atm. A two-parameter kinetic law based on a Langmuir−Hinshelwood rate expression, using activity coefficients from the UNIFAC method, was used. The kinetic parameters are kc = 2.39 × 109 exp[−6200.9/T (K)] (mol gcat−1 min−1) and ks,D = 2.25 × 10−4 exp[3303.1/T (K)]. The activation energy of the reaction is 51.55 kJ mol−1. This work is an important step for further implementation of an integrated reaction−separation process, such as a simulated moving-bed reactor. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901635j [article] Oxygenated biofuels from butanol for diesel blends: synthesis of the acetal 1,1-dibutoxyethane catalyzed by amberlyst-15 Ion-exchange resin [texte imprimé] / Nuno S. Graça, Auteur ; Luis S. Pais, Auteur ; Viviana M. T. M. Silva, Auteur . - 2010 . - pp 6763–6771. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 15 (Août 2010) . - pp 6763–6771 Mots-clés : Biofuels  butanol  Dibutoxyethane. Résumé : The synthesis of 1,1-dibutoxyethane or acetaldehyde dibutylacetal was studied in a batch reactor by reacting butanol and acetaldehyde in a liquid phase, using Amberlyst-15 as the catalyst. The reaction equilibrium constant was experimentally determined in the temperature range 20−40 °C at 6 atm, where Ka = 0.00959 exp[1755.3/T (K)]. The standard properties of the reaction at 298.15 K were estimated: ΔH° = −14.59 kJ mol−1, ΔG° = −3.07 kJ mol−1, and ΔS° = −38.64 J mol−1 K−1. Kinetic experiments were performed in the temperature range 10−50 °C at 6 atm. A two-parameter kinetic law based on a Langmuir−Hinshelwood rate expression, using activity coefficients from the UNIFAC method, was used. The kinetic parameters are kc = 2.39 × 109 exp[−6200.9/T (K)] (mol gcat−1 min−1) and ks,D = 2.25 × 10−4 exp[3303.1/T (K)]. The activation energy of the reaction is 51.55 kJ mol−1. This work is an important step for further implementation of an integrated reaction−separation process, such as a simulated moving-bed reactor. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901635j