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Phase transformation of guanosine 5-monophosphate in continuous couette—taylor crystallizer / Anh-Tuan Nguyen 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. 3483–3493 Titre : Phase transformation of guanosine 5-monophosphate in continuous couette—taylor crystallizer : experiments and numerical modeling for kinetics Type de document : texte imprimé Auteurs : Anh-Tuan Nguyen, Auteur ; Jong-Min Kim, Auteur ; Sang-Mok Chang, Auteur Année de publication : 2011 Article en page(s) : pp. 3483–3493 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Kinetics  Numerical  simulation  Crystallizer  Phase  transformation Résumé : The phase transformation of guanosine 5-monophosphate (GMP) during drowning-out crystallization in a continuous Couette-Taylor (CT) crystallizer was studied experimentally and numerically. At a steady state, the phase transformation of the amorphous GMP into hydrate crystals was monitored along the axial direction of the CT crystallizer when varying the crystallization conditions, including the rotation speed of the inner cylinder of the crystallizer and the feed concentration. As a result, the phase transformation was significantly facilitated when increasing the rotation speed, due to the enhanced dissolution of the amorphous GMP, as well as the growth of the hydrate crystals. For the numerical modeling, simple material balances were derived for three kinds of GMP: the amorphous GMP, hydrate crystals, and GMP concentration in the solution, under the assumption of plug flow behavior for the fluid motion in the CT crystallizer. The simple model predictions matched well with the experimental profiles for the three kinds of GMP along the axial direction of the crystallizer, allowing estimates for the kinetics of the phase transformation, including the mass transfer coefficients for dissolution and growth. According to the model predictions, the rates of amorphous GMP dissolution and hydrate crystal growth were both competitive to control the phase transformation in the CT crystallizer, and about 10 times higher than those in a stirred tank crystallizer. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23944515 [article] Phase transformation of guanosine 5-monophosphate in continuous couette—taylor crystallizer : experiments and numerical modeling for kinetics [texte imprimé] / Anh-Tuan Nguyen, Auteur ; Jong-Min Kim, Auteur ; Sang-Mok Chang, Auteur . - 2011 . - pp. 3483–3493. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 6 (Mars 2011) . - pp. 3483–3493 Mots-clés : Kinetics  Numerical  simulation  Crystallizer  Phase  transformation Résumé : The phase transformation of guanosine 5-monophosphate (GMP) during drowning-out crystallization in a continuous Couette-Taylor (CT) crystallizer was studied experimentally and numerically. At a steady state, the phase transformation of the amorphous GMP into hydrate crystals was monitored along the axial direction of the CT crystallizer when varying the crystallization conditions, including the rotation speed of the inner cylinder of the crystallizer and the feed concentration. As a result, the phase transformation was significantly facilitated when increasing the rotation speed, due to the enhanced dissolution of the amorphous GMP, as well as the growth of the hydrate crystals. For the numerical modeling, simple material balances were derived for three kinds of GMP: the amorphous GMP, hydrate crystals, and GMP concentration in the solution, under the assumption of plug flow behavior for the fluid motion in the CT crystallizer. The simple model predictions matched well with the experimental profiles for the three kinds of GMP along the axial direction of the crystallizer, allowing estimates for the kinetics of the phase transformation, including the mass transfer coefficients for dissolution and growth. According to the model predictions, the rates of amorphous GMP dissolution and hydrate crystal growth were both competitive to control the phase transformation in the CT crystallizer, and about 10 times higher than those in a stirred tank crystallizer. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23944515

Taylor vortex effect on phase transformation of guanosine 5 - monophosphate in drowning - out crystallization / Anh-Tuan Nguyen in Industrial & engineering chemistry research, Vol. 49 N° 10 (Mai 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp 4865–4872 Titre : Taylor vortex effect on phase transformation of guanosine 5 - monophosphate in drowning - out crystallization Type de document : texte imprimé Auteurs : Anh-Tuan Nguyen, Auteur Année de publication : 2010 Article en page(s) : pp 4865–4872 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Monophosphate  Crystallization Résumé : A continuous Couette−Taylor (CT) crystallizer exploiting a Taylor vortex was developed to promote the phase transformation of guanosine 5-monophosphate (GMP). In drowning-out crystallization, amorphous GMP is initially generated and then transformed into hydrate GMP crystals via the consecutive dissolution of the amorphous GMP and nucleation and growth of hydrate GMP crystals. Because of the intensive mixing of the Taylor vortex, the dissolution of the amorphous GMP and growth of the hydrate GMP crystals were both markedly promoted, allowing the phase transformation to be completed within a mean residence time of 5 min, even with a high GMP feed concentration of 150 g/L and moderate rotation speed of 300 rpm This result was at least 5 times faster than the phase transformation in a mixed suspension, mixed product removal (MSMPR) crystallizer under the same crystallization conditions. The phase transformation efficiency of the Taylor vortex over the turbulent eddy in the MSMPR crystallizer was explained in terms of the effectiveness of the turbulence for the mass transfer at the solid−liquid interface. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901932t [article] Taylor vortex effect on phase transformation of guanosine 5 - monophosphate in drowning - out crystallization [texte imprimé] / Anh-Tuan Nguyen, Auteur . - 2010 . - pp 4865–4872. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp 4865–4872 Mots-clés : Monophosphate  Crystallization Résumé : A continuous Couette−Taylor (CT) crystallizer exploiting a Taylor vortex was developed to promote the phase transformation of guanosine 5-monophosphate (GMP). In drowning-out crystallization, amorphous GMP is initially generated and then transformed into hydrate GMP crystals via the consecutive dissolution of the amorphous GMP and nucleation and growth of hydrate GMP crystals. Because of the intensive mixing of the Taylor vortex, the dissolution of the amorphous GMP and growth of the hydrate GMP crystals were both markedly promoted, allowing the phase transformation to be completed within a mean residence time of 5 min, even with a high GMP feed concentration of 150 g/L and moderate rotation speed of 300 rpm This result was at least 5 times faster than the phase transformation in a mixed suspension, mixed product removal (MSMPR) crystallizer under the same crystallization conditions. The phase transformation efficiency of the Taylor vortex over the turbulent eddy in the MSMPR crystallizer was explained in terms of the effectiveness of the turbulence for the mass transfer at the solid−liquid interface. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901932t