Performance and long term stability of mesoporous silica membranes for desalination

Elma, Muthia, Yacou, Christelle, Diniz da Costa, Joao C and Wang, David K. (2013) Performance and long term stability of mesoporous silica membranes for desalination. Membranes, 3 3: 136-150. doi:10.3390/membranes3030136

Author Elma, Muthia
Yacou, Christelle
Diniz da Costa, Joao C
Wang, David K.
Title Performance and long term stability of mesoporous silica membranes for desalination
Journal name Membranes   Check publisher's open access policy
ISSN 2077-0375
Publication date 2013-09
Year available 2013
Sub-type Article (original research)
DOI 10.3390/membranes3030136
Open Access Status DOI
Volume 3
Issue 3
Start page 136
End page 150
Total pages 15
Place of publication Basel, Switzerland
Publisher M D P I
Collection year 2014
Language eng
Formatted abstract
This work shows the preparation of silica membranes by a two-step sol-gel
method using tetraethyl orthosilicate in ethanolic solution by employing nitric acid and
ammonia as co-catalysts. The sols prepared in pH 6 resulted in the lowest concentration of
silanol (Si–OH) species to improve hydrostability and the optimized conditions for film
coating. The membrane was tested to desalinate 0.3–15 wt % synthetic sodium chloride
(NaCl) solutions at a feed temperature of 22 °C followed by long term membrane
performance of up to 250 h in 3.5 wt % NaCl solution. Results show that the water flux
(and salt rejection) decrease with increasing salt concentration delivering an average value
of 9.5 kg m–2 h–1 (99.6%) and 1.55 kg m–2 h–1 (89.2%) from the 0.3 and 15 wt % saline
feed solutions, respectively. Furthermore, the permeate salt concentration was measured to
be less than 600 ppm for testing conditions up to 5 wt % saline feed solutions, achieving
below the recommended standard for potable water. Long term stability shows that the
membrane performance in water flux was stable for up to 150 h, and slightly reduced from
thereon, possibly due to the blockage of large hydrated ions in the micropore constrictions
of the silica matrix. However, the integrity of the silica matrix was not affected by the long
term testing as excellent salt rejection of >99% was maintained for over 250 h.
Keyword Mesoporous
Q-Index Code C1
Q-Index Status Confirmed Code
Institutional Status UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: School of Chemical Engineering Publications
Official 2014 Collection
Version Filter Type
Citation counts: Scopus Citation Count Cited 9 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Wed, 28 Aug 2013, 16:49:11 EST by Mr David Wang on behalf of School of Chemical Engineering