Please use this identifier to cite or link to this item:
Full metadata record
DC FieldValueLanguage
dc.contributor.authorXu, Danen
dc.identifier.citationXu, D. (2011). Chitosan-based adsorbents & nanocomposite membranes for separation applications. Doctoral thesis, Nanyang Technological University, Singapore.en
dc.description.abstractChitosan (CS) is an important biomaterial widely used in purification and separation applications. This project has developed two novel CS-based materials for industrial applications, i.e. (1) CS hydrogel beads for wastewater treatment, and (2) CS nanocomposite membranes for pervaporation separations. In application (1), native CS beads were modified with ammonium sulfate to remove anionic dyes in aqueous solutions at a high pH of 8.2, which was designated for direct treatment of wastewater discharged from textile plants. The adsorption capacities of the modified CS beads towards acid orange-7 (AO-7) and acid red-18 (AR-18) in a fixed bed were 445.6 mg/g and 427.2 mg/g, respectively, which were about 7.4 and 14.4 times of those of the native CS beads at pH 8.2 (60.4 mg/g for AO-7 and 29.7 mg/g for AR-18), respectively. The ion-exchange mechanism of dye adsorption on the modified beads was proposed and verified experimentally. The modified beads were found to be easy to regenerate (with common chemicals) and possessed excellent re-use capability (up to 20 cycles without significant loss in capacity). The fixed bed breakthrough kinetics of AO-7 was measured on the modified beads and was modeled successfully by the Wheeler-Jonas equation with a ‘two-segmented’ approach.en
dc.format.extent149 p.en
dc.subjectDRNTU::Engineering::Chemical engineering::Biotechnological productionen
dc.titleChitosan-based adsorbents & nanocomposite membranes for separation applicationsen
dc.contributor.supervisorWang Keanen
dc.contributor.schoolSchool of Chemical and Biomedical Engineeringen
dc.description.degreeDOCTOR OF PHILOSOPHY (SCBE)en
item.fulltextWith Fulltext-
Appears in Collections:SCBE Theses
Files in This Item:
File Description SizeFormat 
TscbeG0600589L.pdf2.77 MBAdobe PDFThumbnail

Google ScholarTM



Items in DR-NTU are protected by copyright, with all rights reserved, unless otherwise indicated.