Evaluation of citrate-coated magnetic nanoparticles as draw solute for forward osmosis

The initial FO performance was a pure water flux of 17.3 LMH with 20 mg/L MNP in FO mode, however a rapid decline in the water flux occurred due to an interaction between the cellulose triacetate (CTA) membrane and cit-MNPs. A magnetic field control (MFC) FO module was introduced to optimize the use of the cit-MNPs. Magnet field drives the magnetic particle away from the CTA membrane. In MFC FO module, a stable FO initial water flux of 13 LMH resulted with 20 mg/L MNP in FO mode. Our experimental results demonstrated that cit-MNPs can be suitable draw solutes for the FO process and the proposed MFC FO module is believed to be the first device for increasing water flux using magnetic nanoparticles as draw solutes.