Documents disponibles écrits par cet auteur

Hydroformylation of 1 - dodecene in the thermomorphic solvent system dimethylformamide/decane. phase behavior – reaction performance – catalyst recycling / Elisabeth Schafer in Industrial & engineering chemistry research, Vol.51 N° 31 (Août 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol.51 N° 31 (Août 2012) . - pp. 10296-10306 Titre : Hydroformylation of 1 - dodecene in the thermomorphic solvent system dimethylformamide/decane. phase behavior – reaction performance – catalyst recycling Type de document : texte imprimé Auteurs : Elisabeth Schafer, Auteur ; Yvonne Brunsch, Auteur ; Gabriele Sadowski, Auteur Année de publication : 2012 Article en page(s) : pp. 10296-10306 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Recycling  Catalyst Résumé : An economically meaningful hydroformylation of long-chain olefins requires an efficient combination of both a high-yield reaction step and efficient catalyst recycling. The application of thermomorphic multicomponent solvent (TMS) systems allows for optimal reaction as well as catalyst-recycling conditions. In this work, the TMS concept was applied to the homogeneously rhodium-catalyzed hydroformylation of 1-dodecene in the TMS system dimethylformamide (DMF)/decane using Rh(acac)(CO)2/Biphephos as the catalyst system. Thermodynamic investigations focused on the influence of the olefin (hydroformulation educt) and the aldehyde (hydroformylation product) on the phase behavior of the TMS system. Temperature dependent liquid―liquid equilibrium (LLE) data were measured for the binary systems DMF/decane and DMF/1-dodecene and for the ternary systems DMF/decane/1-dodecene and DMF/decane/dodecanal. Additionally, the corresponding LLE data were modeled applying the Perturbed Chain Polar Statistical Associating Fluid Theory (PCP-SAFT) using a heterosegmented approach for modeling the long-chain aldehyde. On the basis of the LLE data, adequate working points for hydroformylation experiments in the TMS system were selected. In these experiments, aldehyde yields of up to 87% with an n/iso ratio of up to 99:1 were achieved. Moreover, the TMS system was successfully applied to catalyst recycling in eight recycling runs with a catalyst leaching of 7 ppm rhodium at lowest. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26234059 [article] Hydroformylation of 1 - dodecene in the thermomorphic solvent system dimethylformamide/decane. phase behavior – reaction performance – catalyst recycling [texte imprimé] / Elisabeth Schafer, Auteur ; Yvonne Brunsch, Auteur ; Gabriele Sadowski, Auteur . - 2012 . - pp. 10296-10306. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol.51 N° 31 (Août 2012) . - pp. 10296-10306 Mots-clés : Recycling  Catalyst Résumé : An economically meaningful hydroformylation of long-chain olefins requires an efficient combination of both a high-yield reaction step and efficient catalyst recycling. The application of thermomorphic multicomponent solvent (TMS) systems allows for optimal reaction as well as catalyst-recycling conditions. In this work, the TMS concept was applied to the homogeneously rhodium-catalyzed hydroformylation of 1-dodecene in the TMS system dimethylformamide (DMF)/decane using Rh(acac)(CO)2/Biphephos as the catalyst system. Thermodynamic investigations focused on the influence of the olefin (hydroformulation educt) and the aldehyde (hydroformylation product) on the phase behavior of the TMS system. Temperature dependent liquid―liquid equilibrium (LLE) data were measured for the binary systems DMF/decane and DMF/1-dodecene and for the ternary systems DMF/decane/1-dodecene and DMF/decane/dodecanal. Additionally, the corresponding LLE data were modeled applying the Perturbed Chain Polar Statistical Associating Fluid Theory (PCP-SAFT) using a heterosegmented approach for modeling the long-chain aldehyde. On the basis of the LLE data, adequate working points for hydroformylation experiments in the TMS system were selected. In these experiments, aldehyde yields of up to 87% with an n/iso ratio of up to 99:1 were achieved. Moreover, the TMS system was successfully applied to catalyst recycling in eight recycling runs with a catalyst leaching of 7 ppm rhodium at lowest. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26234059

Liquid–liquid equilibria of systems with linear aldehydes. experimental data and modeling with PCP-SAFT / Elisabeth Schafer in Industrial & engineering chemistry research, Vol. 51 N° 44 (Novembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 44 (Novembre 2012) . - pp. 14525-14534 Titre : Liquid–liquid equilibria of systems with linear aldehydes. experimental data and modeling with PCP-SAFT Type de document : texte imprimé Auteurs : Elisabeth Schafer, Auteur ; Gabriele Sadowski, Auteur Année de publication : 2013 Article en page(s) : pp. 14525-14534 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Modeling  Phase  equilibrium  Liquid  liquid  equilibrium Résumé : Liquid―liquid equilibrium (LLE) data were measured for the binary system propylene carbonate/decane (288.15 to 403.15 K) as well as for the temary systems propylene carbonate/decane + linear aldehyde (C4, C8, C10, C12, C13) and DMF/decane + linear aldehyde (C4, C8, CIO, C13) at 298.15 K using the analytic method. The reliability of the ternary LLE data is ascertained by employing Othmer―Tobias plots. Concerning the aldehyde distribution coefficients in the ternary systems, a distinctive dependency on the chain length of the aldehyde was observed. The LLE data were modeled with the Perturbed Chain Polar Statistical Associating Fluid Theory (PCP-SAFT) equation of state using a heterosegmented approach for describing the aldehyde molecules. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26620367 [article] Liquid–liquid equilibria of systems with linear aldehydes. experimental data and modeling with PCP-SAFT [texte imprimé] / Elisabeth Schafer, Auteur ; Gabriele Sadowski, Auteur . - 2013 . - pp. 14525-14534. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 44 (Novembre 2012) . - pp. 14525-14534 Mots-clés : Modeling  Phase  equilibrium  Liquid  liquid  equilibrium Résumé : Liquid―liquid equilibrium (LLE) data were measured for the binary system propylene carbonate/decane (288.15 to 403.15 K) as well as for the temary systems propylene carbonate/decane + linear aldehyde (C4, C8, C10, C12, C13) and DMF/decane + linear aldehyde (C4, C8, CIO, C13) at 298.15 K using the analytic method. The reliability of the ternary LLE data is ascertained by employing Othmer―Tobias plots. Concerning the aldehyde distribution coefficients in the ternary systems, a distinctive dependency on the chain length of the aldehyde was observed. The LLE data were modeled with the Perturbed Chain Polar Statistical Associating Fluid Theory (PCP-SAFT) equation of state using a heterosegmented approach for describing the aldehyde molecules. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26620367

Minimal experimental data set required for estimating PCP - SAFT parameters / Katja Albers in Industrial & engineering chemistry research, Vol. 50 N° 20 (Octobre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 20 (Octobre 2011) . - pp. 11746–11754 Titre : Minimal experimental data set required for estimating PCP - SAFT parameters Type de document : texte imprimé Auteurs : Katja Albers, Auteur ; Gabriele Sadowski, Auteur Année de publication : 2011 Article en page(s) : pp. 11746–11754 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Equation  Parameter  estimation. Résumé : The pure-component parameters of the Perturbed Chain Polar-Statistical Associating Fluid Theory (PCP-SAFT) equation of state are usually fitted to experimental data over broad temperature ranges. Against a background of limited experimental data, this article examines the amount and type of experimental data that are minimally required for safe parameter estimation. For nonassociating components, a minimal data set containing three data points is sufficient. For associating components, five data points are sufficient. The influence of vapor-pressure data on parameter estimation and the modeling results is larger than that of liquid-volume data. The temperature ranges of the experimental data can be chosen to be as small as 5 K for all of the data, except for the vapor pressures of associating components. These data require a range of at least 20 K. Application of the parameters fitted to the minimal experimental data set led to convincing results for the modeling of pure-component properties and binary mixtures. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2010803 [article] Minimal experimental data set required for estimating PCP - SAFT parameters [texte imprimé] / Katja Albers, Auteur ; Gabriele Sadowski, Auteur . - 2011 . - pp. 11746–11754. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 20 (Octobre 2011) . - pp. 11746–11754 Mots-clés : Equation  Parameter  estimation. Résumé : The pure-component parameters of the Perturbed Chain Polar-Statistical Associating Fluid Theory (PCP-SAFT) equation of state are usually fitted to experimental data over broad temperature ranges. Against a background of limited experimental data, this article examines the amount and type of experimental data that are minimally required for safe parameter estimation. For nonassociating components, a minimal data set containing three data points is sufficient. For associating components, five data points are sufficient. The influence of vapor-pressure data on parameter estimation and the modeling results is larger than that of liquid-volume data. The temperature ranges of the experimental data can be chosen to be as small as 5 K for all of the data, except for the vapor pressures of associating components. These data require a range of at least 20 K. Application of the parameters fitted to the minimal experimental data set led to convincing results for the modeling of pure-component properties and binary mixtures. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2010803

Modeling liquid – liquid equilibria of polyimide solutions / Lisa Hesse in Industrial & engineering chemistry research, Vol. 51 N° 1 (Janvier 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 1 (Janvier 2012) . - pp. 539–546 Titre : Modeling liquid – liquid equilibria of polyimide solutions Type de document : texte imprimé Auteurs : Lisa Hesse, Auteur ; Gabriele Sadowski, Auteur Année de publication : 2012 Article en page(s) : pp. 539–546 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Nanofiltration  polymer Résumé : The mutual affinity of volatile organic compounds (VOCs) and the active polymer layer of dense organic solvent nanofiltration (OSN) membranes is an important property that influences the separation efficiency. Therefore, the affinity between active layer materials and VOCs was investigated by measuring the liquid–liquid equilibria (LLE) between neat polymers used as active layer materials and VOCs. The measured phase equilibria are modeled using the thermodynamic PC-SAFT (perturbed chain statistical associating fluid theory) model. This model allows for estimation of the pressure- and temperature-dependent chemical potentials of VOCs and membrane materials in feeds, membranes, and permeates. Two polyimides (P84 and Matrimid 5218) were selected as typical OSN membrane materials, and five different VOCs (n-hexane, ethyl acetate, 2-propanol, ethanol, and toluene) were considered. It was found that all miscibility gaps between the polyimides and VOCs are open miscibility gaps. The miscibility gaps of Matrimid 5218 and VOCs are much smaller than those of P84 with all VOCs. By means of the PC-SAFT equation of state, the phase behavior of the two polyimides with all considered VOCs could be well described. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2011142 [article] Modeling liquid – liquid equilibria of polyimide solutions [texte imprimé] / Lisa Hesse, Auteur ; Gabriele Sadowski, Auteur . - 2012 . - pp. 539–546. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 1 (Janvier 2012) . - pp. 539–546 Mots-clés : Nanofiltration  polymer Résumé : The mutual affinity of volatile organic compounds (VOCs) and the active polymer layer of dense organic solvent nanofiltration (OSN) membranes is an important property that influences the separation efficiency. Therefore, the affinity between active layer materials and VOCs was investigated by measuring the liquid–liquid equilibria (LLE) between neat polymers used as active layer materials and VOCs. The measured phase equilibria are modeled using the thermodynamic PC-SAFT (perturbed chain statistical associating fluid theory) model. This model allows for estimation of the pressure- and temperature-dependent chemical potentials of VOCs and membrane materials in feeds, membranes, and permeates. Two polyimides (P84 and Matrimid 5218) were selected as typical OSN membrane materials, and five different VOCs (n-hexane, ethyl acetate, 2-propanol, ethanol, and toluene) were considered. It was found that all miscibility gaps between the polyimides and VOCs are open miscibility gaps. The miscibility gaps of Matrimid 5218 and VOCs are much smaller than those of P84 with all VOCs. By means of the PC-SAFT equation of state, the phase behavior of the two polyimides with all considered VOCs could be well described. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2011142

Modeling pH and solubilities in aqueous multisolute amino acid solutions / Jan-Bernd Grosse Daldrup in Industrial & engineering chemistry research, Vol. 50 N° 6 (Mars 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 6 (Mars 2011) . - pp. 3503–3509 Titre : Modeling pH and solubilities in aqueous multisolute amino acid solutions Type de document : texte imprimé Auteurs : Jan-Bernd Grosse Daldrup, Auteur ; Christoph Held, Auteur ; Gabriele Sadowski, Auteur Année de publication : 2011 Article en page(s) : pp. 3503–3509 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Amino  acids  Aqueous  multisolute Résumé : The solubility of amino acids is highly depending on the prevailing pH value. However, this dependency is neglected in the state-of-the-art modeling of solubilities in multisolute solutions. In order to describe the pH-dependency of the solubilities, the PC-SAFT model is applied to aqueous solutions containing two amino acids accounting for their dissociation/association equilibria. This approach is applied to four ternary mixtures with pronounced pH-dependent solubility behavior allowing for a good description of experimental amino acid solubilities depending on temperature, cosolute concentration, and pH value. The systems considered within this work each contain two amino acids which show big differences in pI, i.e., l-glutamic acid or l/dl-aspartic acid on the one hand and glycine or l-serine on the other hand, respectively. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1010367 [article] Modeling pH and solubilities in aqueous multisolute amino acid solutions [texte imprimé] / Jan-Bernd Grosse Daldrup, Auteur ; Christoph Held, Auteur ; Gabriele Sadowski, Auteur . - 2011 . - pp. 3503–3509. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 6 (Mars 2011) . - pp. 3503–3509 Mots-clés : Amino  acids  Aqueous  multisolute Résumé : The solubility of amino acids is highly depending on the prevailing pH value. However, this dependency is neglected in the state-of-the-art modeling of solubilities in multisolute solutions. In order to describe the pH-dependency of the solubilities, the PC-SAFT model is applied to aqueous solutions containing two amino acids accounting for their dissociation/association equilibria. This approach is applied to four ternary mixtures with pronounced pH-dependent solubility behavior allowing for a good description of experimental amino acid solubilities depending on temperature, cosolute concentration, and pH value. The systems considered within this work each contain two amino acids which show big differences in pI, i.e., l-glutamic acid or l/dl-aspartic acid on the one hand and glycine or l-serine on the other hand, respectively. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1010367