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Updated: May 27, 2026
09:39
Proof-of-Concept for Gas-Entrapping Membranes Derived from Water-Loving SiO2/Si/SiO2 Wafers for Green Desalination
Published on: March 1, 2020
Cobalt oxide silica membranes for desalination
Chun Xiang C Lin1, Li Ping Ding, Simon Smart
1The University of Queensland, FIMLab - Films and Inorganic Membrane Laboratory, School of Chemical Engineering, Brisbane, Qld 4072, Australia.
Journal of Colloid and Interface Science
|November 15, 2011
Summary
Cobalt oxide silica (CoO(x)Si) membranes demonstrate high salt rejection (>99%) for desalination across various concentrations. Elevated temperatures increase water flux, showing potential for efficient water purification.
Area of Science:
- Materials Science
- Chemical Engineering
- Environmental Science
Background:
- Membrane-based desalination is crucial for addressing global water scarcity.
- Development of novel materials with enhanced performance is essential for improving desalination efficiency.
Purpose of the Study:
- To investigate the potential of cobalt oxide silica (CoO(x)Si) membranes for desalination.
- To evaluate the performance of these membranes across a range of salt concentrations and temperatures.
Main Methods:
- Sol-gel synthesis of CoO(x)Si xerogels using TEOS, cobalt nitrate hydrate, and peroxide.
- Hydrothermal treatment to densify xerogels and assess stability.
- Fabrication of CoO(x)Si membranes and testing under varying feed salinities and temperatures.
Main Results:
- CoO(x)Si xerogels synthesized at pH 5 showed the highest resistance to hydrothermal degradation.
- Membranes exhibited stable pore structures, maintaining molecular sieving dimensions.
- Water flux increased with elevated feed temperatures and decreased with higher salt concentrations.
- Consistent salt rejection exceeding 99% was achieved, irrespective of temperature or salinity.
Conclusions:
- Cobalt oxide silica membranes show significant promise for effective desalination of brackish water, seawater, and brine.
- The membranes demonstrate excellent hydrostability and high salt rejection capabilities.
- Optimizing synthesis conditions and operating parameters can further enhance water flux for practical applications.
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