Summary: | 碩士 === 中興大學 === 化學工程學系所 === 95 === In this study, thin and dense polyethersulfone membranes with thickness of 4-12 μm and water content of 4.2-8.3 wt% were prepared. By conducting the batch FO (forward osmosis) process and the flow FO forward osmosis process, the water flux achieved by the sulfonated PES membrane was much higher than those obtained for the PES membranes, but its NaCl rejection was lower. The PES membrane with larger thickness had higher salt rejection and lower water flux. Moreover, by using the ultrafiltraion membrane ZM 500 as support layer, the PES membranes exhibited higher salt rejection and lower water flux. Especially in the flow process, the use of support layer had significant effect on water flux and NaCl rejection. As a result of the flow FO process, the optimal FO membrane obtained in this study is the PES 30 membrane (3.5±0.5 μm) with ZM 500 as support layer. Its flux is 0.65 (L m-2 hr-1) under 60 mL/min operation and it could attain high salt rejection (higher than 98.2%).
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