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Hydroformylation of 1-butene on Rh catalyst / Tapio Salmi in Industrial & engineering chemistry research, Vol. 48 N°3 (Février 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N°3 (Février 2009) . - p. 1325–1331 Titre : Hydroformylation of 1-butene on Rh catalyst Type de document : texte imprimé Auteurs : Tapio Salmi, Auteur ; Johan Ahlkvist, Auteur ; Andreas Bernas, Auteur Année de publication : 2009 Article en page(s) : p. 1325–1331 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Hydroformylation  Rhodium  catalyst  Butene Résumé : Kinetics of homogeneously catalyzed hydroformylation of 1-butene was studied in a pressurized semibatch autoclave reactor. Kinetics was determined for a reaction mixture, which consisted of 1-butene, carbon monoxide, hydrogen, a rhodium-based catalyst, and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate as a solvent. The following reaction parameters were investigated: temperature (70−100 °C), total pressure (1−3 MPa), catalyst concentration (100−200 ppm), catalyst (Rh)-to-ligand ratio, and the initial ratio of the synthesis gas (hydrogen and carbon dioxide) components. The solubility of 1-butene, carbon monoxide, and hydrogen in the solvent was determined by precise pressure and weight measurements and modeled mathematically. The main reaction products were pentanal (P) and 2-methylbutanal (MB), while trace amounts of cis-2- and trans-2-butene were detected as reaction intermediates. The ratio of the main products (P and MB) was practically independent of temperature, but the ligand-to-Rh ratio affected considerably the product distribution: an increasing ratio preferred the formation of pentanal (P). Increasing total pressure diminished the yield of pentanal (P). On the basis of the experimentally recorded kinetic data, a stoichiometric scheme was constructed and simplified. The kinetic data were combined with solubility models, and the parameters of an empirical power-law rate model were determined by nonlinear regression analysis. The kinetic parameters were well identified and physically reasonable being in accordance with qualitative observations. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800215t [article] Hydroformylation of 1-butene on Rh catalyst [texte imprimé] / Tapio Salmi, Auteur ; Johan Ahlkvist, Auteur ; Andreas Bernas, Auteur . - 2009 . - p. 1325–1331. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N°3 (Février 2009) . - p. 1325–1331 Mots-clés : Hydroformylation  Rhodium  catalyst  Butene Résumé : Kinetics of homogeneously catalyzed hydroformylation of 1-butene was studied in a pressurized semibatch autoclave reactor. Kinetics was determined for a reaction mixture, which consisted of 1-butene, carbon monoxide, hydrogen, a rhodium-based catalyst, and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate as a solvent. The following reaction parameters were investigated: temperature (70−100 °C), total pressure (1−3 MPa), catalyst concentration (100−200 ppm), catalyst (Rh)-to-ligand ratio, and the initial ratio of the synthesis gas (hydrogen and carbon dioxide) components. The solubility of 1-butene, carbon monoxide, and hydrogen in the solvent was determined by precise pressure and weight measurements and modeled mathematically. The main reaction products were pentanal (P) and 2-methylbutanal (MB), while trace amounts of cis-2- and trans-2-butene were detected as reaction intermediates. The ratio of the main products (P and MB) was practically independent of temperature, but the ligand-to-Rh ratio affected considerably the product distribution: an increasing ratio preferred the formation of pentanal (P). Increasing total pressure diminished the yield of pentanal (P). On the basis of the experimentally recorded kinetic data, a stoichiometric scheme was constructed and simplified. The kinetic data were combined with solubility models, and the parameters of an empirical power-law rate model were determined by nonlinear regression analysis. The kinetic parameters were well identified and physically reasonable being in accordance with qualitative observations. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800215t

Kinetic modeling of propene hydroformylation with Rh/TPP and Rh/CHDPP catalysts / Andreas Bernas in Industrial & engineering chemistry research, Vol. 47 N° 13 (Juillet 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 N° 13 (Juillet 2008) . - p. 4317–4324 Titre : Kinetic modeling of propene hydroformylation with Rh/TPP and Rh/CHDPP catalysts Type de document : texte imprimé Auteurs : Andreas Bernas, Auteur ; Paivi Maki-Arvela, Auteur ; Juha Lehtonen, Auteur ; Tapio Salmi, Auteur Année de publication : 2008 Article en page(s) : p. 4317–4324 Note générale : Bibliogr. p. 4324 Langues : Anglais (eng) Mots-clés : Propene  hydroformylation;  Solubility;  Rhodium/triphenylphosphine  catalysts Résumé : Hydroformylation of propene to isobutyraldehyde and n-butyraldehyde was studied in the kinetic regime in a semibatch stainless steel reactor at 70−115 °C and 1−15 bar overpressure in 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate solvent with rhodium/cyclohexyl diphenylphosphine (Rh/CHDPP) and rhodium/triphenylphosphine (Rh/TPP) catalysts. The influence of process parameters such as Rh concentration (50−250 ppm), ligand mass fraction (0−10 wt %), H2-to-CO ratio, and stirring power was investigated and the influence of solvent concentration was studied by using mixtures of valeraldehyde and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate as solvent. The solubility of propene, H2, and CO in 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate was measured in the same reactor. Rh/CHDPP showed lower normal/isometric aldehyde ratio (n/i) than Rh/TPP. The rate was temperature and pressure dependent, while the Rh concentration or syngas composition did not have any significant impact. The n/i ratio was always independent of the conversion, but dependent on the ligand concentration: higher ligand concentration promoted isobutyraldehyde formation. Based on experimentally recorded kinetic data, a stoichiometric scheme was proposed and parameters of power-law rate models were determined by using nonlinear regression analysis. The experimental system was described as a perfectly mixed gas−liquid reactor. As showed by sensitivity analysis, the kinetic parameters were well identified and physically reasonable and they were in accordance with qualitative observations. The kinetic models with a degree of explanation of more than 0.9 described the formation of the products with satisfying accuracy. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie071401r [article] Kinetic modeling of propene hydroformylation with Rh/TPP and Rh/CHDPP catalysts [texte imprimé] / Andreas Bernas, Auteur ; Paivi Maki-Arvela, Auteur ; Juha Lehtonen, Auteur ; Tapio Salmi, Auteur . - 2008 . - p. 4317–4324. Bibliogr. p. 4324 Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 N° 13 (Juillet 2008) . - p. 4317–4324 Mots-clés : Propene  hydroformylation;  Solubility;  Rhodium/triphenylphosphine  catalysts Résumé : Hydroformylation of propene to isobutyraldehyde and n-butyraldehyde was studied in the kinetic regime in a semibatch stainless steel reactor at 70−115 °C and 1−15 bar overpressure in 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate solvent with rhodium/cyclohexyl diphenylphosphine (Rh/CHDPP) and rhodium/triphenylphosphine (Rh/TPP) catalysts. The influence of process parameters such as Rh concentration (50−250 ppm), ligand mass fraction (0−10 wt %), H2-to-CO ratio, and stirring power was investigated and the influence of solvent concentration was studied by using mixtures of valeraldehyde and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate as solvent. The solubility of propene, H2, and CO in 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate was measured in the same reactor. Rh/CHDPP showed lower normal/isometric aldehyde ratio (n/i) than Rh/TPP. The rate was temperature and pressure dependent, while the Rh concentration or syngas composition did not have any significant impact. The n/i ratio was always independent of the conversion, but dependent on the ligand concentration: higher ligand concentration promoted isobutyraldehyde formation. Based on experimentally recorded kinetic data, a stoichiometric scheme was proposed and parameters of power-law rate models were determined by using nonlinear regression analysis. The experimental system was described as a perfectly mixed gas−liquid reactor. As showed by sensitivity analysis, the kinetic parameters were well identified and physically reasonable and they were in accordance with qualitative observations. The kinetic models with a degree of explanation of more than 0.9 described the formation of the products with satisfying accuracy. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie071401r

Kinetics of cinnamaldehyde hydrogenation by supported ionic liquid catalysts (SILCA) / Pasi Virtanen in Industrial & engineering chemistry research, Vol. 48 N° 23 (Décembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10335–10342 Titre : Kinetics of cinnamaldehyde hydrogenation by supported ionic liquid catalysts (SILCA) Type de document : texte imprimé Auteurs : Pasi Virtanen, Auteur ; Tapio Salmi, Auteur ; Jyri-Pekka Mikkola, Auteur Année de publication : 2010 Article en page(s) : pp. 10335–10342 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Kinetics--Cinnamaldehyde--Hydrogenation--Supported--Ionic  Liquid--Catalysts  (SILCA) Résumé : The research of ionic liquids and their applications in catalysis are attracting increasing attention in chemistry and chemical engineering. A supported ionic liquid catalyst (SILCA) consists of immobilized catalytic species (e.g., transition-metal particles, metal complexes, or enzymes) residing in an ionic liquid layer immobilized on a porous solid support. The kinetics of cinnamaldehyde hydrogenation over SILCAs that contained palladium nanoparticles in ionic liquid, which, in turn, was immobilized on active carbon cloth (ACC), was studied and modeled in detail. A mechanistic kinetic model, which describes the differences of the activity and selectivity of the catalysts consisting of different ionic liquids, was developed. The model explained the experimental results well. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901041z [article] Kinetics of cinnamaldehyde hydrogenation by supported ionic liquid catalysts (SILCA) [texte imprimé] / Pasi Virtanen, Auteur ; Tapio Salmi, Auteur ; Jyri-Pekka Mikkola, Auteur . - 2010 . - pp. 10335–10342. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10335–10342 Mots-clés : Kinetics--Cinnamaldehyde--Hydrogenation--Supported--Ionic  Liquid--Catalysts  (SILCA) Résumé : The research of ionic liquids and their applications in catalysis are attracting increasing attention in chemistry and chemical engineering. A supported ionic liquid catalyst (SILCA) consists of immobilized catalytic species (e.g., transition-metal particles, metal complexes, or enzymes) residing in an ionic liquid layer immobilized on a porous solid support. The kinetics of cinnamaldehyde hydrogenation over SILCAs that contained palladium nanoparticles in ionic liquid, which, in turn, was immobilized on active carbon cloth (ACC), was studied and modeled in detail. A mechanistic kinetic model, which describes the differences of the activity and selectivity of the catalysts consisting of different ionic liquids, was developed. The model explained the experimental results well. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901041z

Reversible autocatalytic hydrolysis of alkyl formate / Olatunde Jogunola in Industrial & engineering chemistry research, Vol. 49 N° 9 (Mai 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 9 (Mai 2010) . - pp. 4099–4106 Titre : Reversible autocatalytic hydrolysis of alkyl formate : kinetic and reactor modeling Type de document : texte imprimé Auteurs : Olatunde Jogunola, Auteur ; Tapio Salmi, Auteur ; Kari Eranen, Auteur Année de publication : 2010 Article en page(s) : pp. 4099–4106 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Hydrolysis  Kinetic Résumé : The kinetics and thermodynamics of alkyl formate hydrolysis in liquid phase were studied in a laboratory-scale autoclave at temperatures between 333 and 383 K using different molar ratios of the reactants. The process was found to exhibit an autocatalytic effect due to the acid formed. More so, the rate of neutral hydrolysis of ethyl formate is faster compared to methyl formate in the uncatalyzed reaction. However, the autocatalytic effect is more pronounced in methyl formate hydrolysis. In addition, the effect of adding a small amount of formic acid as an initial charge upon the equilibrium conversion and kinetics was investigated, and it was found that the addition improved the reaction rate by reducing the induction period but it suppressed slightly the equilibrium conversion. A kinetic model was proposed to explain these experimental trends, and the model agreed well with the experimental results. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie902031d [article] Reversible autocatalytic hydrolysis of alkyl formate : kinetic and reactor modeling [texte imprimé] / Olatunde Jogunola, Auteur ; Tapio Salmi, Auteur ; Kari Eranen, Auteur . - 2010 . - pp. 4099–4106. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 9 (Mai 2010) . - pp. 4099–4106 Mots-clés : Hydrolysis  Kinetic Résumé : The kinetics and thermodynamics of alkyl formate hydrolysis in liquid phase were studied in a laboratory-scale autoclave at temperatures between 333 and 383 K using different molar ratios of the reactants. The process was found to exhibit an autocatalytic effect due to the acid formed. More so, the rate of neutral hydrolysis of ethyl formate is faster compared to methyl formate in the uncatalyzed reaction. However, the autocatalytic effect is more pronounced in methyl formate hydrolysis. In addition, the effect of adding a small amount of formic acid as an initial charge upon the equilibrium conversion and kinetics was investigated, and it was found that the addition improved the reaction rate by reducing the induction period but it suppressed slightly the equilibrium conversion. A kinetic model was proposed to explain these experimental trends, and the model agreed well with the experimental results. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie902031d

Skeletal isomerization of butene in fixed beds. part 2. kinetic and flow modeling / Matias Kangas in Industrial & engineering chemistry research, Vol. 47 n°15 (Août 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°15 (Août 2008) . - p. 5413–5426 Titre : Skeletal isomerization of butene in fixed beds. part 2. kinetic and flow modeling Type de document : texte imprimé Auteurs : Matias Kangas, Auteur ; Tapio Salmi, Auteur ; Dmitry Yu. Murzin, Auteur Année de publication : 2008 Article en page(s) : p. 5413–5426 Note générale : Bibliogr. p. 5325-5326 Langues : Anglais (eng) Mots-clés : Zeolite  catalyzed  hydrocarbon  --  packed  bed;  Butene  --  skeletal  isomerization Résumé : Starting from detailed experimental studies of reaction kinetics, catalyst deactivation, and reactor flow conditions, mathematical models describing the dynamic reactor performance in zeolite catalyzed hydrocarbon transformations in packed beds have been developed. By using a sequential calculation procedure that involved changes in reactor models, solvers, and optimizers, kinetic parameters were regressed for two promising catalysts. Utilizing the estimated parameters and the developed kinetic and flow models, the skeletal isomerization of n-butene was accurately modeled. A proper description of adsorption and deactivation was shown to be as important as the kinetic formulation itself in obtaining good fits to the experimental results. Separable kinetics and deactivation functions were used. Relating the activity of the catalysts to the fraction of noncoked zeolite surface predicted the measured specific surface area to within 5-10%, indicating that reaction takes place throughout the whole catalyst pellet. Structure effects were observed in the estimated composite kinetic parameters. Protonated cyclopropane branching was much easier over H-FER, whereas n-butene codimerization with isobutene was significantly more facile over H-TON. Similar composite activation energies for the β-scission steps were obtained for both zeolites. The estimated reaction enthalpies for the oligomerization-cracking surface reaction were substantially lower than the thermodynamically calculated heats of reaction for the corresponding gas phase reactions, suggesting that olefin addition proceeds via the stepwise oligomerization mechanism. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800062m [article] Skeletal isomerization of butene in fixed beds. part 2. kinetic and flow modeling [texte imprimé] / Matias Kangas, Auteur ; Tapio Salmi, Auteur ; Dmitry Yu. Murzin, Auteur . - 2008 . - p. 5413–5426. Bibliogr. p. 5325-5326 Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°15 (Août 2008) . - p. 5413–5426 Mots-clés : Zeolite  catalyzed  hydrocarbon  --  packed  bed;  Butene  --  skeletal  isomerization Résumé : Starting from detailed experimental studies of reaction kinetics, catalyst deactivation, and reactor flow conditions, mathematical models describing the dynamic reactor performance in zeolite catalyzed hydrocarbon transformations in packed beds have been developed. By using a sequential calculation procedure that involved changes in reactor models, solvers, and optimizers, kinetic parameters were regressed for two promising catalysts. Utilizing the estimated parameters and the developed kinetic and flow models, the skeletal isomerization of n-butene was accurately modeled. A proper description of adsorption and deactivation was shown to be as important as the kinetic formulation itself in obtaining good fits to the experimental results. Separable kinetics and deactivation functions were used. Relating the activity of the catalysts to the fraction of noncoked zeolite surface predicted the measured specific surface area to within 5-10%, indicating that reaction takes place throughout the whole catalyst pellet. Structure effects were observed in the estimated composite kinetic parameters. Protonated cyclopropane branching was much easier over H-FER, whereas n-butene codimerization with isobutene was significantly more facile over H-TON. Similar composite activation energies for the β-scission steps were obtained for both zeolites. The estimated reaction enthalpies for the oligomerization-cracking surface reaction were substantially lower than the thermodynamically calculated heats of reaction for the corresponding gas phase reactions, suggesting that olefin addition proceeds via the stepwise oligomerization mechanism. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800062m

The dissolution kinetics of gibbsite in sodium hydroxide at ambient pressure / Henrik Grenman in Industrial & engineering chemistry research, Vol. 49 N° 6 (Mars 2010) 

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