Please use this identifier to cite or link to this item:
Title: Understanding of low osmotic efficiency in forward osmosis: Experiments and modeling
Authors: Su, J. 
Chung, T.-S. 
Helmer, B.J.
de Wit, J.S.
Keywords: Concentration profile
Forward osmosis
Osmotic efficiency
Transport resistance
Water flux
Issue Date: 5-Mar-2013
Citation: Su, J., Chung, T.-S., Helmer, B.J., de Wit, J.S. (2013-03-05). Understanding of low osmotic efficiency in forward osmosis: Experiments and modeling. Desalination 313 : 156-165. ScholarBank@NUS Repository.
Abstract: This study discloses the critical factors that result in the low osmotic efficiency in forward osmosis (FO). Specifically, dual-layer hollow fiber membranes are prepared with newly-synthesized cellulose acetate propionate (CAP) as the outer active layer and commercial cellulose acetate (CA) as the inner sublayer. By carefully analyzing the hollow fiber cross section images, the porosity of the sublayer is found to be nonuniformly distributed at different locations. Viewing the membrane matrix as three consecutive layers, i.e., the active layer, the sublayer and the interface between them, the draw solute concentration profiles within each layer, the osmotic pressure gradients across each layer, and the transport resistance of each layer are determined. One interesting observation is that the active layer of the CAP-CA hollow fibers creates much larger resistance than the interface and the sublayer, indicating that the low osmotic efficiency (i.e., low water flux) is mainly due to the low water permeability of the active layer while internal concentration polarization (ICP) within the sublayer is less important. For any membranes, the active layer-sublayer interface also creates certain transport resistance. These findings provide a valuable reference for the understanding of FO and the design of advanced FO membranes. © 2013 Elsevier B.V.
Source Title: Desalination
ISSN: 00119164
DOI: 10.1016/j.desal.2012.12.022
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.


checked on Dec 6, 2019


checked on Dec 6, 2019

Page view(s)

checked on Dec 1, 2019

Google ScholarTM



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.