WAter Desalination
by Inverse osmosis

Desalination of seawater and purification of polluted waters are essential processes to produce clean water for human, industrial, and agriculture uses.

Current extraction and purification approaches suffer of limited selectivity and efficiency. Hence, the development of smart membranes with high efficiency so that clean water production is made more controlled, requires less time and needs less energy is one of the main challenge in the field.

This proposal aims to the fabrication of new fibrous membranes for water desalination by inverse osmosis. Membranes will be made electrospinning chitosan and polyacrylonitrile and then photocrosslinking the fibers to guarantee mechanical and chemical robustness.

Three types of approaches will be tested. First, both polymers will be spun at once. Second, chitosan, in the presence of polyethyleneoxide as a template will be spun onto pre-prepared polyacrylonitrile membranes made by casting. Third, two consecutive electrospinning steps will be carried out: first, polyacrylonitrile is spun from its solution, then chitosan/polyethylene oxide mixtures are spun onto polyacrylonitrile electrospun fibers (two-layer electrospun fibers).

The preparation conditions such as mixture composition, the electrospinning process and the photoinduced crosslinking reactions will be optimized to obtain the most proper membranes in terms of morphology, porosity, hydrophilicity, thermal stability, and antimicrobial activity.

The obtained membranes will be characterized by different techniques including SEM, FT-IR, water contact angle, DSC, and TGA.

The membranes will be tested for reverse osmosis process: the molecular weight cut-off of the membranes, using solutions of polyethylene glycol of different molecular weight, as well as the assessment of the selectivity performance using different divalent and monovalent salt solutions will be investigated. In addition, the fouling and chlorine resistance of the fabricated membranes will be measure.