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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