Documents disponibles écrits par cet auteur

Double - skinned forward osmosis membranes for reducing internal concentration polarization within the porous sublayer / Kai Yu Wang 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. 4824–4831 Titre : Double - skinned forward osmosis membranes for reducing internal concentration polarization within the porous sublayer Type de document : texte imprimé Auteurs : Kai Yu Wang, Auteur ; Rui Chin Ong, Auteur ; Tai-Shung Chung, Auteur Année de publication : 2010 Article en page(s) : pp. 4824–4831 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Osmosis  Membranes Résumé : A scheme to fabricate forward osmosis membranes comprising a highly porous sublayer sandwiched between two selective skin layers via phase inversion was proposed. One severe deficiency of existing composite and asymmetric membranes used in forward osmosis is the presence of unfavorable internal concentration polarization within the porous support layer that hinders both (i) separation (salt flux) and (ii) the performance (water flux). The double skin layers of the tailored membrane may mitigate the internal concentration polarization by preventing the salt and other solutes in the draw solution from penetrating into the membrane porous support. The prototype double-skinned cellulose acetate membrane displayed a water flux of 48.2 L·m−2·h−1 and lower reverse salt transport of 6.5 g·m−2·h−1 using 5.0 M MgCl2 as the draw solution in a forward osmosis process performed at 22 °C. This can be attributed to the effective salt rejection by the double skin layers and the low water transport resistance within the porous support layer. The prospects of utilizing the double-selective layer membranes may have potential application in forward osmosis for desalination. This study may help pave the way to improve the membrane design for the forward osmosis process. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901592d [article] Double - skinned forward osmosis membranes for reducing internal concentration polarization within the porous sublayer [texte imprimé] / Kai Yu Wang, Auteur ; Rui Chin Ong, Auteur ; Tai-Shung Chung, Auteur . - 2010 . - pp. 4824–4831. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 10 (Mai 2010) . - pp. 4824–4831 Mots-clés : Osmosis  Membranes Résumé : A scheme to fabricate forward osmosis membranes comprising a highly porous sublayer sandwiched between two selective skin layers via phase inversion was proposed. One severe deficiency of existing composite and asymmetric membranes used in forward osmosis is the presence of unfavorable internal concentration polarization within the porous support layer that hinders both (i) separation (salt flux) and (ii) the performance (water flux). The double skin layers of the tailored membrane may mitigate the internal concentration polarization by preventing the salt and other solutes in the draw solution from penetrating into the membrane porous support. The prototype double-skinned cellulose acetate membrane displayed a water flux of 48.2 L·m−2·h−1 and lower reverse salt transport of 6.5 g·m−2·h−1 using 5.0 M MgCl2 as the draw solution in a forward osmosis process performed at 22 °C. This can be attributed to the effective salt rejection by the double skin layers and the low water transport resistance within the porous support layer. The prospects of utilizing the double-selective layer membranes may have potential application in forward osmosis for desalination. This study may help pave the way to improve the membrane design for the forward osmosis process. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901592d

Novel cellulose esters for forward osmosis membranes / Rui Chin Ong in Industrial & engineering chemistry research, Vol. 51 N° 49 (Décembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 49 (Décembre 2012) . - pp. 16135-16145 Titre : Novel cellulose esters for forward osmosis membranes Type de document : texte imprimé Auteurs : Rui Chin Ong, Auteur ; Tai-Shung Chung, Auteur ; Bradley J. Helmer, Auteur Année de publication : 2013 Article en page(s) : pp. 16135-16145 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Osmosis Résumé : Syntheses and evaluation of novel cellulose esters consisting of a wide range of chemical compositions targeted for forward osmosis membrane fabrication have been carried out. Preliminary studies on the effects of the degree of substitution of hydroxyl, acetyl, and propionyl or butyryl functional groups on the membrane formation and permeation characteristics were conducted. Experiments results show that cellulose esters with high content of hydrophobic functional groups content exhibit great salt rejection, because of low water solubility and small hydrated free volume of hydrophobic cellulose esters. However, as the content of bulky hydrophobic functional groups increases, there is an accompanying increase in free volume due to poor chain packing, which causes a decrease in salt rejection. A high OH content in cellulose esters results in membranes with high salt and water permeation. Among the evaluated cellulose esters, those which have the highest hydrophobicity are unable to form membranes with defect-free selective layers via normal phase inversion casting conditions. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26732138 [article] Novel cellulose esters for forward osmosis membranes [texte imprimé] / Rui Chin Ong, Auteur ; Tai-Shung Chung, Auteur ; Bradley J. Helmer, Auteur . - 2013 . - pp. 16135-16145. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 49 (Décembre 2012) . - pp. 16135-16145 Mots-clés : Osmosis Résumé : Syntheses and evaluation of novel cellulose esters consisting of a wide range of chemical compositions targeted for forward osmosis membrane fabrication have been carried out. Preliminary studies on the effects of the degree of substitution of hydroxyl, acetyl, and propionyl or butyryl functional groups on the membrane formation and permeation characteristics were conducted. Experiments results show that cellulose esters with high content of hydrophobic functional groups content exhibit great salt rejection, because of low water solubility and small hydrated free volume of hydrophobic cellulose esters. However, as the content of bulky hydrophobic functional groups increases, there is an accompanying increase in free volume due to poor chain packing, which causes a decrease in salt rejection. A high OH content in cellulose esters results in membranes with high salt and water permeation. Among the evaluated cellulose esters, those which have the highest hydrophobicity are unable to form membranes with defect-free selective layers via normal phase inversion casting conditions. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26732138