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Liquid – liquid flow in a capillary microreactor / Jovan Jovanovic in Industrial & engineering chemistry research, Vol. 51 N° 2 (Janvier 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1015-1026 Titre : Liquid – liquid flow in a capillary microreactor : Hydrodynamic flow patterns and extraction performance Type de document : texte imprimé Auteurs : Jovan Jovanovic, Auteur ; Evgeny V. Rebrov, Auteur ; T. A. (Xander) Nijhuis, Auteur Année de publication : 2012 Article en page(s) : pp. 1015-1026 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Flow  field  Hydrodynamics  Microreactor  Liquid  liquid  flow Résumé : The capillary microreactor, with four stable operating flow patterns and a throughput range from grams per hour to kilograms per hour, presents an attractive alternative to chip-based and microstructured reactors for laboratory- and pilot-scale applications. In this article, results for the extraction of 2-butanol from toluene under different flow patterns in a water/toluene flow in long capillary microreactors are presented. The effects of the capillary length (0.4―2.2 m), flow rate (0.1-12 mL/min), and aqueous-to-organic volumetric flow ratio (0.25―9) on the slug, bubbly, parallel, and annular flow hydrodynamics were investigated. Weber-number-dependent flow maps were composed for capillary lengths of 0.4 and 2 m that were used to interpret the flow pattern formation in terms of surface tension and inertia forces. When the capillary length was decreased from 2 to 0.4 m, a transition from annular to parallel flow was observed. The capillary length had little influence on slug and bubbly flows. The flow patterns were evaluated in terms of stability, surface-to-volume ratio, throughput, and extraction efficiency. Slug and bubbly flow operations yielded 100% thermodynamic extraction efficiency, and increasing the aqueous-to-organic volumetric ratio to 9 allowed for 99% 2-butanol extraction. The parallel and annular flow operating windows were limited by the capillary length, thus yielding maximum 2-butanol extractions of 30% and 47% for parallel and annular flows, respectively. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476434 [article] Liquid – liquid flow in a capillary microreactor : Hydrodynamic flow patterns and extraction performance [texte imprimé] / Jovan Jovanovic, Auteur ; Evgeny V. Rebrov, Auteur ; T. A. (Xander) Nijhuis, Auteur . - 2012 . - pp. 1015-1026. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 2 (Janvier 2012) . - pp. 1015-1026 Mots-clés : Flow  field  Hydrodynamics  Microreactor  Liquid  liquid  flow Résumé : The capillary microreactor, with four stable operating flow patterns and a throughput range from grams per hour to kilograms per hour, presents an attractive alternative to chip-based and microstructured reactors for laboratory- and pilot-scale applications. In this article, results for the extraction of 2-butanol from toluene under different flow patterns in a water/toluene flow in long capillary microreactors are presented. The effects of the capillary length (0.4―2.2 m), flow rate (0.1-12 mL/min), and aqueous-to-organic volumetric flow ratio (0.25―9) on the slug, bubbly, parallel, and annular flow hydrodynamics were investigated. Weber-number-dependent flow maps were composed for capillary lengths of 0.4 and 2 m that were used to interpret the flow pattern formation in terms of surface tension and inertia forces. When the capillary length was decreased from 2 to 0.4 m, a transition from annular to parallel flow was observed. The capillary length had little influence on slug and bubbly flows. The flow patterns were evaluated in terms of stability, surface-to-volume ratio, throughput, and extraction efficiency. Slug and bubbly flow operations yielded 100% thermodynamic extraction efficiency, and increasing the aqueous-to-organic volumetric ratio to 9 allowed for 99% 2-butanol extraction. The parallel and annular flow operating windows were limited by the capillary length, thus yielding maximum 2-butanol extractions of 30% and 47% for parallel and annular flows, respectively. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25476434

Phase-transfer catalysis in segmented flow in a microchannel / Jovan Jovanović in Industrial & engineering chemistry research, Vol. 49 N° 6 (Mars 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2681–2687 Titre : Phase-transfer catalysis in segmented flow in a microchannel : fluidic control of selectivity and productivity Type de document : texte imprimé Auteurs : Jovan Jovanović, Auteur ; Evgeny V. Rebrov, Auteur ; T. A. (Xander) Nijhuis, Auteur Année de publication : 2010 Article en page(s) : pp. 2681–2687 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Catalysis  in  Segmented  Flow  Microchannel  Fluidic  Selectivity  Productivity Résumé : Precise control over the interfacial area of aqueous and organic slugs in segmented flow in a microchannel reactor provides an attractive means to optimize the yield and productivity of a phase-transfer-catalyzed reaction. Herein, we report the selective alkylation of phenylacetonitrile to the monoalkylated product in a microchannel of 250-μm internal diameter operated in a continuous and solvent-free manner in the slug-flow regime. The conversion of phenylacetonitrile increased from 40% to 99% as a result of a 97% larger slug surface-to-volume ratio when the volumetric aqueous-to-organic phase flow ratio was raised from 1.0 to 6.1 at the same residence time. The larger surface-to-volume ratio significantly promoted catalyst phase transfer but decreased selectivity because of the simultaneous increase of the rate of the consecutive reaction to the dialkylated product. There exists an optimum flow ratio with a maximum productivity. Conversion and selectivity in the microchannel reactor were both found to be significantly larger than in a stirred reactor. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9017918 [article] Phase-transfer catalysis in segmented flow in a microchannel : fluidic control of selectivity and productivity [texte imprimé] / Jovan Jovanović, Auteur ; Evgeny V. Rebrov, Auteur ; T. A. (Xander) Nijhuis, Auteur . - 2010 . - pp. 2681–2687. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2681–2687 Mots-clés : Catalysis  in  Segmented  Flow  Microchannel  Fluidic  Selectivity  Productivity Résumé : Precise control over the interfacial area of aqueous and organic slugs in segmented flow in a microchannel reactor provides an attractive means to optimize the yield and productivity of a phase-transfer-catalyzed reaction. Herein, we report the selective alkylation of phenylacetonitrile to the monoalkylated product in a microchannel of 250-μm internal diameter operated in a continuous and solvent-free manner in the slug-flow regime. The conversion of phenylacetonitrile increased from 40% to 99% as a result of a 97% larger slug surface-to-volume ratio when the volumetric aqueous-to-organic phase flow ratio was raised from 1.0 to 6.1 at the same residence time. The larger surface-to-volume ratio significantly promoted catalyst phase transfer but decreased selectivity because of the simultaneous increase of the rate of the consecutive reaction to the dialkylated product. There exists an optimum flow ratio with a maximum productivity. Conversion and selectivity in the microchannel reactor were both found to be significantly larger than in a stirred reactor. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9017918