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Crystallization and agglomeration kinetics of hydromagnesite in the reactive system MgCl2–Na2CO3–NaOH–H2O / Junfeng Wang in Industrial & engineering chemistry research, Vol. 51 N° 23 (Juin 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 23 (Juin 2012) . - pp. 7874–7883 Titre : Crystallization and agglomeration kinetics of hydromagnesite in the reactive system MgCl2–Na2CO3–NaOH–H2O Type de document : texte imprimé Auteurs : Junfeng Wang, Auteur ; Zhibao Li, Auteur Année de publication : 2012 Article en page(s) : pp. 7874–7883 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Kinetics  Hydromagnesite Résumé : The reactive crystallization kinetics of hydromagnesite (4MgCO3·Mg(OH)2·4H2O) for the MgCl2–Na2CO3–NaOH–H2O system has been systematically investigated in a continuously operated mixed-suspension mixed-product removal (MSMPR) crystallizer for the first time. Determination of the effects of reactive temperature and OH– ion on magnesium carbonate hydrates in the above system was conducted through a batch crystallization experiment, and the crystallization temperature of 80 °C for the precipitation of regular spherical-like hydromagnesite was selected for the kinetics study. The relative supersaturation for hydromagnesite is obtained based on the activity coefficients calculated by the Pitzer model. The growth rate, nucleation rate, and agglomeration kernel are determined on the basis of the agglomeration population balance equation, and their kinetic equations are then correlated in terms of power law kinetic expressions. The orders of volume growth rate and linear growth rate with respect to the relative supersaturation are 1.55 and 0.95, respectively. The magma density has an important effect on the nucleation rate of hydromagnesite particles. However, the expression of β MT–0.39 for hydromagnesite agglomeration shows that the magma density has a negative effect on the agglomeration kernel. All of these will provide a basis for the design and analysis of industrial crystallizers. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300213c [article] Crystallization and agglomeration kinetics of hydromagnesite in the reactive system MgCl2–Na2CO3–NaOH–H2O [texte imprimé] / Junfeng Wang, Auteur ; Zhibao Li, Auteur . - 2012 . - pp. 7874–7883. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 23 (Juin 2012) . - pp. 7874–7883 Mots-clés : Kinetics  Hydromagnesite Résumé : The reactive crystallization kinetics of hydromagnesite (4MgCO3·Mg(OH)2·4H2O) for the MgCl2–Na2CO3–NaOH–H2O system has been systematically investigated in a continuously operated mixed-suspension mixed-product removal (MSMPR) crystallizer for the first time. Determination of the effects of reactive temperature and OH– ion on magnesium carbonate hydrates in the above system was conducted through a batch crystallization experiment, and the crystallization temperature of 80 °C for the precipitation of regular spherical-like hydromagnesite was selected for the kinetics study. The relative supersaturation for hydromagnesite is obtained based on the activity coefficients calculated by the Pitzer model. The growth rate, nucleation rate, and agglomeration kernel are determined on the basis of the agglomeration population balance equation, and their kinetic equations are then correlated in terms of power law kinetic expressions. The orders of volume growth rate and linear growth rate with respect to the relative supersaturation are 1.55 and 0.95, respectively. The magma density has an important effect on the nucleation rate of hydromagnesite particles. However, the expression of β MT–0.39 for hydromagnesite agglomeration shows that the magma density has a negative effect on the agglomeration kernel. All of these will provide a basis for the design and analysis of industrial crystallizers. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300213c

Density prediction of ionic liquids at different temperatures and pressures using a group contribution equation of state based on electrolyte perturbation theory / Junfeng Wang 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. 4420-4425 Titre : Density prediction of ionic liquids at different temperatures and pressures using a group contribution equation of state based on electrolyte perturbation theory Type de document : texte imprimé Auteurs : Junfeng Wang, Auteur ; Zhibao Li, Auteur ; Chunxi Li, Auteur Année de publication : 2010 Article en page(s) : pp. 4420-4425 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Thermodynamic  properties  Perturbation  theory  Electrolyte  Equations  of  state  Ionic  liquid  Prediction  Density Résumé : Based on the electrolyte perturbation theory, a group contribution equation of state that embodies hard-sphere repulsion, dispersive attraction, and ionic electrostatic interaction energy was established to calculate the density of ionic liquids (ILs). According to this method, each ionic liquid is divided into several groups representing cation, anion, and alkyl substituents. The performance of the model was examined by describing the densities of a large number of imidazolium-based ILs over a wide range of temperatures (293.15―414.15 K) and pressures (0.1-70.43 MPa). A total number of 202 data points of density for 12 ILs and 2 molecular liquids (i.e., I-methylimidazole and 1-ethylimidazole) were used to fit the group parameters, namely, the soft-core diameter σ and the dispersive energy e. The resulting group parameters were used to predict 961 data points of density for 29 ILs at varying temperatures and pressures. The model was found to estimate well the densities of ionic liquids with an overall average relative deviation (ARD) of 0.41% for correlation and an ARD of 0.63% for prediction, which demonstrates the applicability of the model and the rationality of the soft-core diameter and dispersive energy parameters. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=22732930 [article] Density prediction of ionic liquids at different temperatures and pressures using a group contribution equation of state based on electrolyte perturbation theory [texte imprimé] / Junfeng Wang, Auteur ; Zhibao Li, Auteur ; Chunxi Li, Auteur . - 2010 . - pp. 4420-4425. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 9 (Mai 2010) . - pp. 4420-4425 Mots-clés : Thermodynamic  properties  Perturbation  theory  Electrolyte  Equations  of  state  Ionic  liquid  Prediction  Density Résumé : Based on the electrolyte perturbation theory, a group contribution equation of state that embodies hard-sphere repulsion, dispersive attraction, and ionic electrostatic interaction energy was established to calculate the density of ionic liquids (ILs). According to this method, each ionic liquid is divided into several groups representing cation, anion, and alkyl substituents. The performance of the model was examined by describing the densities of a large number of imidazolium-based ILs over a wide range of temperatures (293.15―414.15 K) and pressures (0.1-70.43 MPa). A total number of 202 data points of density for 12 ILs and 2 molecular liquids (i.e., I-methylimidazole and 1-ethylimidazole) were used to fit the group parameters, namely, the soft-core diameter σ and the dispersive energy e. The resulting group parameters were used to predict 961 data points of density for 29 ILs at varying temperatures and pressures. The model was found to estimate well the densities of ionic liquids with an overall average relative deviation (ARD) of 0.41% for correlation and an ARD of 0.63% for prediction, which demonstrates the applicability of the model and the rationality of the soft-core diameter and dispersive energy parameters. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=22732930

Modeling of solid-liquid equilibrium for the [HAE]Cl-MgCl2-H2O system / Junfeng Wang in Industrial & engineering chemistry research, Vol. 50 N° 13 (Juillet 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 13 (Juillet 2011) . - pp. 8314-8322 Titre : Modeling of solid-liquid equilibrium for the [HAE]Cl-MgCl2-H2O system Type de document : texte imprimé Auteurs : Junfeng Wang, Auteur ; Shunping Sun, Auteur ; Zhibao Li, Auteur Année de publication : 2011 Article en page(s) : pp. 8314-8322 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Phase  equilibrium  Liquid  solid  equilibrium  Modeling Résumé : The study of the solid-liquid phase equilibrium for the [HAE]Cl-MgCl2-H2O system is of significance for the preparation of anhydrous magnesium chloride using the thermal decomposition of the complex ([HAE]Cl·MgCl2·6H2O), which is synthesized by the reaction of aniline hydrochloride ([HAE]Cl) and bischofite (MgCl2·6H2O). In this study, a rigorous and thermodynamically consistent representation for the [HAE]Cl-MgCl2-H2O system was developed on the basis of the electrolyte nonrandom two-liquid (ENRTL) activity coefficient model embedded in Aspen Plus. The solubility of [HAE]Cl in water and magnesium chloride solutions over the temperature range from 277 to 370 K was measured by use of the dynamic method. With the equilibrium constant of [HAE]Cl obtained using experimental solubility of [HAE]Cl in water and the phase equilibrium equation, the new ENRTL parameters were obtained by regressing the solubility data for the two binary systems [HAE]Cl-H2O and MgCl2-H2O and the one ternary system [HAE]Cl-MgCl2-H2O at MgCl2 concentrations of 0.51 and 2.17 mol·kg-1. These obtained parameters could accurately predict the solubility for the ternary [HAE]Cl-MgCl2-H2O system at MgCl2 concentrations of 1.05, 1.56, 2.72, 3.21, 3.87, 4.32, and 5.05 mol·kg-1. The values at multiple saturated points at 298.15 and 323.15 K were accurately predicted with help of the newly developed model. The behavior of the ternary [HAE]Cl-MgCl2-H2O system at the two temperatures are successfully visualized with lucidity on an equilateral triangle. All of these will provide a thennodynamic basis for the preparation of the [ HAE] Cl·MgCl2·6H2O complex. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24332157 [article] Modeling of solid-liquid equilibrium for the [HAE]Cl-MgCl2-H2O system [texte imprimé] / Junfeng Wang, Auteur ; Shunping Sun, Auteur ; Zhibao Li, Auteur . - 2011 . - pp. 8314-8322. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 13 (Juillet 2011) . - pp. 8314-8322 Mots-clés : Phase  equilibrium  Liquid  solid  equilibrium  Modeling Résumé : The study of the solid-liquid phase equilibrium for the [HAE]Cl-MgCl2-H2O system is of significance for the preparation of anhydrous magnesium chloride using the thermal decomposition of the complex ([HAE]Cl·MgCl2·6H2O), which is synthesized by the reaction of aniline hydrochloride ([HAE]Cl) and bischofite (MgCl2·6H2O). In this study, a rigorous and thermodynamically consistent representation for the [HAE]Cl-MgCl2-H2O system was developed on the basis of the electrolyte nonrandom two-liquid (ENRTL) activity coefficient model embedded in Aspen Plus. The solubility of [HAE]Cl in water and magnesium chloride solutions over the temperature range from 277 to 370 K was measured by use of the dynamic method. With the equilibrium constant of [HAE]Cl obtained using experimental solubility of [HAE]Cl in water and the phase equilibrium equation, the new ENRTL parameters were obtained by regressing the solubility data for the two binary systems [HAE]Cl-H2O and MgCl2-H2O and the one ternary system [HAE]Cl-MgCl2-H2O at MgCl2 concentrations of 0.51 and 2.17 mol·kg-1. These obtained parameters could accurately predict the solubility for the ternary [HAE]Cl-MgCl2-H2O system at MgCl2 concentrations of 1.05, 1.56, 2.72, 3.21, 3.87, 4.32, and 5.05 mol·kg-1. The values at multiple saturated points at 298.15 and 323.15 K were accurately predicted with help of the newly developed model. The behavior of the ternary [HAE]Cl-MgCl2-H2O system at the two temperatures are successfully visualized with lucidity on an equilateral triangle. All of these will provide a thennodynamic basis for the preparation of the [ HAE] Cl·MgCl2·6H2O complex. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24332157

Photographic study on two-phase flow patterns of water in a single-side heated narrow rectangular channel / Junfeng Wang in Transactions of the ASME . Journal of engineering for gas turbines and power, Vol. 133 N° 5 (Mai 2011) 

Public ISBD [article]  in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 133 N° 5 (Mai 2011) . - 05 p. Titre : Photographic study on two-phase flow patterns of water in a single-side heated narrow rectangular channel Type de document : texte imprimé Auteurs : Junfeng Wang, Auteur ; Yanping Huang, Auteur ; Yanlin Wang, Auteur Année de publication : 2012 Article en page(s) : 05 p. Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Boiling  Channel  flow  Heat  transfer  Photography  Two-phase  flow Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : Visualized experimental observation on flow patterns during flow boiling of water under single-side heated and fluid-inlet subcooled conditions in a vertical narrow rectangular channel with the cross section of 40×3 mm2 have been carried out. Four discernible flow patterns, which names dispersed bubbly, coalesced bubbly, churn flow, and annular flow are observed. Flow visualization in two dimensions of two-phase flow patterns for narrow rectangular channel, which provided clearer evidence to distinguish flow patterns, have been performed. Based on the experimental results, a flow pattern map for single-side heated narrow rectangular channel has been developed and then compared with the exiting maps and flow transition criteria. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ00013 [...] [article] Photographic study on two-phase flow patterns of water in a single-side heated narrow rectangular channel [texte imprimé] / Junfeng Wang, Auteur ; Yanping Huang, Auteur ; Yanlin Wang, Auteur . - 2012 . - 05 p. Génie Mécanique Langues : Anglais (eng) in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 133 N° 5 (Mai 2011) . - 05 p. Mots-clés : Boiling  Channel  flow  Heat  transfer  Photography  Two-phase  flow Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : Visualized experimental observation on flow patterns during flow boiling of water under single-side heated and fluid-inlet subcooled conditions in a vertical narrow rectangular channel with the cross section of 40×3 mm2 have been carried out. Four discernible flow patterns, which names dispersed bubbly, coalesced bubbly, churn flow, and annular flow are observed. Flow visualization in two dimensions of two-phase flow patterns for narrow rectangular channel, which provided clearer evidence to distinguish flow patterns, have been performed. Based on the experimental results, a flow pattern map for single-side heated narrow rectangular channel has been developed and then compared with the exiting maps and flow transition criteria. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ00013 [...]

Solubility and self - consistent modeling of aniline hydrochloride in H – Mg – Na – Ca – Al – Cl – H2O system at the temperature range of 288 – 348 K / Shunping Sun in Industrial & engineering chemistry research, Vol. 51 N° 9 (Mars 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 9 (Mars 2012) . - pp. 3783–3790 Titre : Solubility and self - consistent modeling of aniline hydrochloride in H – Mg – Na – Ca – Al – Cl – H2O system at the temperature range of 288 – 348 K Type de document : texte imprimé Auteurs : Shunping Sun, Auteur ; Junfeng Wang, Auteur ; Zhibao Li, Auteur Année de publication : 2012 Article en page(s) : pp. 3783–3790 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Hydrochloric  acid Résumé : Previous work has proved that the preparation method of anhydrous magnesium chloride by using the thermal decomposition of the complex [HAE]Cl·MgCl2·6H2O is a potential process for commercial application. Normally, the complex [HAE]Cl·MgCl2·6H2O is synthesized by reaction crystallization of aniline hydrochloride (C6H5NH2·HCl, [HAE]Cl) and bischofite (MgCl2·6H2O). The study on the solubility of [HAE]Cl in hydrochloric acid and various chloride salt solutions plays a significant role in the development, analysis, and engineering design for this new process. This work is a continuation of our systematic study of the solubility of [HAE]Cl in different chloride media. The solubility of [HAE]Cl in different concentrations of HCl (1.19–6.98 mol·kg–1), NaCl (0.5–3.8 mol·kg–1), CaCl2 (0.5–4.5 mol·kg–1), AlCl3 (0.5–2.8 mol·kg–1), and their mixed solutions was determined using a dynamic method in the temperature range from 288 to 348 K. With the purpose of improving AspenPlus’s prediction capability, in regard to [HAE]Cl solubility data in the H–Mg–Na–Ca–Al–Cl–H2O systems at various temperatures, new model parameters were obtained via the regression of the experimental solubility of [HAE]Cl in single electrolyte solutions, such as HCl, NaCl, CaCl2, and AlCl3, under atmospheric pressure. With the newly obtained electrolyte NRTL (ENRTL) interaction parameters for [HAE]Cl–NaCl, [HAE]Cl–CaCl2, [HAE]Cl–AlCl3, and AlCl3–H2O, and default parameters for NaCl–H2O and CaCl2–H2O in AspenPlus, a self-consistent model for the system [HAE]–H–Mg–Na–Ca–Al–Cl–H2O was established with the maximum relative deviation of 4.3% between experimental and predicted solubility values. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2013949 [article] Solubility and self - consistent modeling of aniline hydrochloride in H – Mg – Na – Ca – Al – Cl – H2O system at the temperature range of 288 – 348 K [texte imprimé] / Shunping Sun, Auteur ; Junfeng Wang, Auteur ; Zhibao Li, Auteur . - 2012 . - pp. 3783–3790. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 9 (Mars 2012) . - pp. 3783–3790 Mots-clés : Hydrochloric  acid Résumé : Previous work has proved that the preparation method of anhydrous magnesium chloride by using the thermal decomposition of the complex [HAE]Cl·MgCl2·6H2O is a potential process for commercial application. Normally, the complex [HAE]Cl·MgCl2·6H2O is synthesized by reaction crystallization of aniline hydrochloride (C6H5NH2·HCl, [HAE]Cl) and bischofite (MgCl2·6H2O). The study on the solubility of [HAE]Cl in hydrochloric acid and various chloride salt solutions plays a significant role in the development, analysis, and engineering design for this new process. This work is a continuation of our systematic study of the solubility of [HAE]Cl in different chloride media. The solubility of [HAE]Cl in different concentrations of HCl (1.19–6.98 mol·kg–1), NaCl (0.5–3.8 mol·kg–1), CaCl2 (0.5–4.5 mol·kg–1), AlCl3 (0.5–2.8 mol·kg–1), and their mixed solutions was determined using a dynamic method in the temperature range from 288 to 348 K. With the purpose of improving AspenPlus’s prediction capability, in regard to [HAE]Cl solubility data in the H–Mg–Na–Ca–Al–Cl–H2O systems at various temperatures, new model parameters were obtained via the regression of the experimental solubility of [HAE]Cl in single electrolyte solutions, such as HCl, NaCl, CaCl2, and AlCl3, under atmospheric pressure. With the newly obtained electrolyte NRTL (ENRTL) interaction parameters for [HAE]Cl–NaCl, [HAE]Cl–CaCl2, [HAE]Cl–AlCl3, and AlCl3–H2O, and default parameters for NaCl–H2O and CaCl2–H2O in AspenPlus, a self-consistent model for the system [HAE]–H–Mg–Na–Ca–Al–Cl–H2O was established with the maximum relative deviation of 4.3% between experimental and predicted solubility values. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2013949