Documents disponibles écrits par cet auteur

Alternative influence of binary surfactant mixtures on the rate of mass transfer in a liquid - liquid extraction process / Javad Saien in Industrial & engineering chemistry research, Vol. 50 N° 11 (Juin 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 11 (Juin 2011) . - pp. 6925-6932 Titre : Alternative influence of binary surfactant mixtures on the rate of mass transfer in a liquid - liquid extraction process Type de document : texte imprimé Auteurs : Javad Saien, Auteur ; Somayeh Rezabeigy, Auteur Année de publication : 2011 Article en page(s) : pp. 6925-6932 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Liquid  liquid  extraction  Mass  transfer  Surfactant Résumé : The effect of binary mixtures of cationic and nonionic surfactants dodecyltrimethylammonium chloride (DTMAC) and Triton X―100 on hydrodynamic and mass transfer of the liquid-liquid extraction process was investigated. Mass transfer coefficients of acetone from toluene drops to the continuous aqueous phase and inverse direction were obtained. For the acetone analysis, gas chromatography was used. The rate of mass transfer closely relates to the adsorption behavior of surfactant mixtures at the interface, and the overall mass transfer coefficient, Kod, exhibits the similar variation of surfactants molecular interaction at the interface. The minimum mass transfer rate appears at Triton bulk mole fractions (surfactants based only) of about 0.01 and 0.2 and the maximum at about 0.6. The latter introduces the best composition to achieve the highest separation rate. Meanwhile, the mass transfer coefficient decreases rapidly with a tiny amount of total surfactants under a constant bulk mole fraction, and the solute transfer is always more for dispersed to continuous phase direction. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24199910 [article] Alternative influence of binary surfactant mixtures on the rate of mass transfer in a liquid - liquid extraction process [texte imprimé] / Javad Saien, Auteur ; Somayeh Rezabeigy, Auteur . - 2011 . - pp. 6925-6932. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 11 (Juin 2011) . - pp. 6925-6932 Mots-clés : Liquid  liquid  extraction  Mass  transfer  Surfactant Résumé : The effect of binary mixtures of cationic and nonionic surfactants dodecyltrimethylammonium chloride (DTMAC) and Triton X―100 on hydrodynamic and mass transfer of the liquid-liquid extraction process was investigated. Mass transfer coefficients of acetone from toluene drops to the continuous aqueous phase and inverse direction were obtained. For the acetone analysis, gas chromatography was used. The rate of mass transfer closely relates to the adsorption behavior of surfactant mixtures at the interface, and the overall mass transfer coefficient, Kod, exhibits the similar variation of surfactants molecular interaction at the interface. The minimum mass transfer rate appears at Triton bulk mole fractions (surfactants based only) of about 0.01 and 0.2 and the maximum at about 0.6. The latter introduces the best composition to achieve the highest separation rate. Meanwhile, the mass transfer coefficient decreases rapidly with a tiny amount of total surfactants under a constant bulk mole fraction, and the solute transfer is always more for dispersed to continuous phase direction. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24199910

Interfacial tension of hydrocarbon + different pH aqueous phase systems in the presence of triton X-100 / Javad Saien in Industrial & engineering chemistry research, Vol. 49 N° 7 (Avril 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 7 (Avril 2010) . - pp. 3228–3235 Titre : Interfacial tension of hydrocarbon + different pH aqueous phase systems in the presence of triton X-100 Type de document : texte imprimé Auteurs : Javad Saien, Auteur ; Somayeh Akbari, Auteur Année de publication : 2010 Article en page(s) : pp. 3228–3235 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Interfacial  Hydrocarbon  Hydrocarbont  pH  Aqueous  Triton  X-100 Résumé : The influence of adsorption of low amounts (1.00 × 10−8−2.33 × 10−5 mol·L−1) of Triton X-100 and hydroxyl ion (appropriate to the practical pH range of 6.00−9.37) on the interfacial tension of two recommended systems for liquid−liquid extraction investigations, toluene−water and cumene−water, at 25.0 °C is studied. Solutions with a maximum relative standard deviation in concentration of ±1% have been used; meanwhile, the uncertainty for measured interfacial tensions is ±0.03 mN·m−1. From the data and in agreement with the commonly used Szyszkowski model, a much higher adsorption effectiveness, but a lower adsorption tendency, for Triton is concluded. The influence of Triton in lowering interfacial tension is significantly weakened by hydroxyl ions. Meanwhile, the estimated interfacial composition and interaction parameter (using the theory of nonideal interactions in binary mixtures) are strongly dependent on the bulk mole fraction. The hydroxyl ion shows maximum adsorption at the bulk mole fractions around 0.50 and 0.60, where a high rate of mass transfer could be expected. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900402u [article] Interfacial tension of hydrocarbon + different pH aqueous phase systems in the presence of triton X-100 [texte imprimé] / Javad Saien, Auteur ; Somayeh Akbari, Auteur . - 2010 . - pp. 3228–3235. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 7 (Avril 2010) . - pp. 3228–3235 Mots-clés : Interfacial  Hydrocarbon  Hydrocarbont  pH  Aqueous  Triton  X-100 Résumé : The influence of adsorption of low amounts (1.00 × 10−8−2.33 × 10−5 mol·L−1) of Triton X-100 and hydroxyl ion (appropriate to the practical pH range of 6.00−9.37) on the interfacial tension of two recommended systems for liquid−liquid extraction investigations, toluene−water and cumene−water, at 25.0 °C is studied. Solutions with a maximum relative standard deviation in concentration of ±1% have been used; meanwhile, the uncertainty for measured interfacial tensions is ±0.03 mN·m−1. From the data and in agreement with the commonly used Szyszkowski model, a much higher adsorption effectiveness, but a lower adsorption tendency, for Triton is concluded. The influence of Triton in lowering interfacial tension is significantly weakened by hydroxyl ions. Meanwhile, the estimated interfacial composition and interaction parameter (using the theory of nonideal interactions in binary mixtures) are strongly dependent on the bulk mole fraction. The hydroxyl ion shows maximum adsorption at the bulk mole fractions around 0.50 and 0.60, where a high rate of mass transfer could be expected. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900402u

Mass transfer enhancement in liquid−liquid extraction with very dilute aqueous salt solutions / Javad Saien in Industrial & engineering chemistry research, Vol. 48 N° 22 (Novembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 22 (Novembre 2009) . - pp. 10008–10014 Titre : Mass transfer enhancement in liquid−liquid extraction with very dilute aqueous salt solutions Type de document : texte imprimé Auteurs : Javad Saien, Auteur ; Fatemeh Ashrafi, Auteur Année de publication : 2010 Article en page(s) : pp. 10008–10014 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Liquid−liquid  extraction  chemical  system  Mass  transfer Résumé : The effect of very low salt addition in the recommended liquid−liquid extraction chemical system of toluene−acetone−water was investigated with circulating single drops and in both of the mass transfer directions. By adding sodium chloride, potassium chloride, and potassium iodide, within the concentration range of 10−6−10−4 mol/L, into the continuous phase and under constant pH, the mass transfer rate finds enhancements to about 425%. A high trend of variation was observed for the salt concentrations until only about 10−5 mol/L. This phenomenon can be attributed to the hydration of ions which favors acetone to be transferred easier in the aqueous phase. Small drops are usually more benefited, and the rate of mass transfer is greater for the dispersed to continuous phase direction under similar conditions due to a higher dominant extraction fraction, whereas the drop size decreases in this direction. The effectiveness of salts in this matter appeared to be in the order of NaCl > KCl > KI. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900542w [article] Mass transfer enhancement in liquid−liquid extraction with very dilute aqueous salt solutions [texte imprimé] / Javad Saien, Auteur ; Fatemeh Ashrafi, Auteur . - 2010 . - pp. 10008–10014. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 22 (Novembre 2009) . - pp. 10008–10014 Mots-clés : Liquid−liquid  extraction  chemical  system  Mass  transfer Résumé : The effect of very low salt addition in the recommended liquid−liquid extraction chemical system of toluene−acetone−water was investigated with circulating single drops and in both of the mass transfer directions. By adding sodium chloride, potassium chloride, and potassium iodide, within the concentration range of 10−6−10−4 mol/L, into the continuous phase and under constant pH, the mass transfer rate finds enhancements to about 425%. A high trend of variation was observed for the salt concentrations until only about 10−5 mol/L. This phenomenon can be attributed to the hydration of ions which favors acetone to be transferred easier in the aqueous phase. Small drops are usually more benefited, and the rate of mass transfer is greater for the dispersed to continuous phase direction under similar conditions due to a higher dominant extraction fraction, whereas the drop size decreases in this direction. The effectiveness of salts in this matter appeared to be in the order of NaCl > KCl > KI. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900542w

Mass transfer from nanofluid single drops in liquid – liquid extraction process / Javad Saien in Industrial & engineering chemistry research, Vol. 51 N° 14 (Avril 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 14 (Avril 2012) . - pp. 5157-5166 Titre : Mass transfer from nanofluid single drops in liquid – liquid extraction process Type de document : texte imprimé Auteurs : Javad Saien, Auteur ; Hamid Bamdadi, Auteur Année de publication : 2012 Article en page(s) : pp. 5157-5166 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Liquid  liquid  extraction  Drop  Mass  transfer Résumé : This investigation is focused on the behavior of nanofluid single drops in the liquid―liquid extraction process. The chemical system of toluene―acetic acid―water was used, and the drops were organic nanofluids containing magnetite or alumina nanoparticles. Synthesized nanoparticles were modified with fatty acids for hydrophobicity and ease of dispersion in the organic phase and were then characterized using different methods. Maximum enhancements in the rate of mass transfer of 157% and 121% were achieved using about 0.002 wt % magnetite and alumina nanoparticles, respectively; however, a decreasing variation was observed at higher concentrations. The microconvection and particle aggregation due to the interpenetration layers can provide this kind of variation. For the aim of modeling, the determined enhancement factors were correlated with an empirical expression that can be used, together with the Newman equation, for the prediction of the overall mass-transfer coefficient. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25783423 [article] Mass transfer from nanofluid single drops in liquid – liquid extraction process [texte imprimé] / Javad Saien, Auteur ; Hamid Bamdadi, Auteur . - 2012 . - pp. 5157-5166. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 14 (Avril 2012) . - pp. 5157-5166 Mots-clés : Liquid  liquid  extraction  Drop  Mass  transfer Résumé : This investigation is focused on the behavior of nanofluid single drops in the liquid―liquid extraction process. The chemical system of toluene―acetic acid―water was used, and the drops were organic nanofluids containing magnetite or alumina nanoparticles. Synthesized nanoparticles were modified with fatty acids for hydrophobicity and ease of dispersion in the organic phase and were then characterized using different methods. Maximum enhancements in the rate of mass transfer of 157% and 121% were achieved using about 0.002 wt % magnetite and alumina nanoparticles, respectively; however, a decreasing variation was observed at higher concentrations. The microconvection and particle aggregation due to the interpenetration layers can provide this kind of variation. For the aim of modeling, the determined enhancement factors were correlated with an empirical expression that can be used, together with the Newman equation, for the prediction of the overall mass-transfer coefficient. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25783423

Mass transfer from single drops and the influence of temperature / Javad Saien in Industrial & engineering chemistry research, Vol. 51 N° 21 (Mai 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 21 (Mai 2012) . - pp. 7364–7372 Titre : Mass transfer from single drops and the influence of temperature Type de document : texte imprimé Auteurs : Javad Saien, Auteur ; Shabnam Daliri, Auteur Année de publication : 2012 Article en page(s) : pp. 7364–7372 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Mass  transfer Résumé : Temperature can alter the performance of conventional liquid–liquid extraction columns in which one phase is dispersed inside another phase. In this research, the influence of temperature on the extraction process was investigated using a toluene–acetic acid–water chemical system with dominant mass transfer resistance in the organic phase. Single drop experiments with a range of drop size within 2.49–3.77 mm and temperature within 15–40 °C were performed. Results demonstrate significant impact of temperature on the rate of mass transfer with an average enhancement of 93.6% in overall mass transfer coefficient while small drops are benefited more. Having lower contributions by drop size and terminal velocity, the extraction efficiency is the most effective term in this regard which itself is increased by increasing molecular diffusivity in the organic dispersed phase. For the aim of modeling, effective diffusivity was substituted for molecular diffusivity in Newman’s equation and consequently, a reliable empirical equation was derived for the enhancement factor of diffusivity as a function of dimensionless variables. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300649d [article] Mass transfer from single drops and the influence of temperature [texte imprimé] / Javad Saien, Auteur ; Shabnam Daliri, Auteur . - 2012 . - pp. 7364–7372. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 21 (Mai 2012) . - pp. 7364–7372 Mots-clés : Mass  transfer Résumé : Temperature can alter the performance of conventional liquid–liquid extraction columns in which one phase is dispersed inside another phase. In this research, the influence of temperature on the extraction process was investigated using a toluene–acetic acid–water chemical system with dominant mass transfer resistance in the organic phase. Single drop experiments with a range of drop size within 2.49–3.77 mm and temperature within 15–40 °C were performed. Results demonstrate significant impact of temperature on the rate of mass transfer with an average enhancement of 93.6% in overall mass transfer coefficient while small drops are benefited more. Having lower contributions by drop size and terminal velocity, the extraction efficiency is the most effective term in this regard which itself is increased by increasing molecular diffusivity in the organic dispersed phase. For the aim of modeling, effective diffusivity was substituted for molecular diffusivity in Newman’s equation and consequently, a reliable empirical equation was derived for the enhancement factor of diffusivity as a function of dimensionless variables. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300649d