(514f) Condition Optimization for the Fabrication of Desalination Thin Film Composite Membranes

Reverse osmosis is one of the most spread technologies all over the world for salty water purification, in which thin film composite (TFC) is the common form of membranes used. In this paper, we examined the effects of various membrane fabrication conditions on the TFC membrane performance including 1) m-phenylenediamine (MPD) and trimesoyl chloride (TMC) exposure times; 2) different ways for the support PSU sheets phase inversion; 3) the support layer sheet thickness and 4) drying temperature for the fabricated membranes. The operation conditions used in this work were: 300 psi, 25 °C, 2000 ppm NaCl, and the samples were run for at least 8 hours. It was found that the best salt rejection and water flux results were obtained when the reaction time was short during the interfacial polymerization and when the plate was immersed vertically during the phase inversion for PSU support preparation. Increasing the PSU sheet thickness increased proportionally the salt rejection and decreased the water flux. And increasing the drying temperature led to an increase in the salt rejection and water flux for short reaction time. Based on the study, a TFC membrane with salt rejection of 98.8 ± 0.5 % and water flux of 76.1 ± 2.7 L/m²hr was fabricated using 25 sec MPD contacting time and 5 sec TMC reaction time and 110 °C drying temperature. To the best of our knowledge, this result is the best ever reported for simple prepared TFC membranes.

References

1- Mohammed Kadhom, Jun Yin, Baolin Deng, “A Thin Film Nanocomposite Membrane with MCM-41 Silica Nanoparticles for Brackish Water Purification”, Membranes, 6, 50, (2016) 1-12.