| Summary: | 碩士 === 嘉南藥理大學 === 環境工程與科學系 === 106 === In this research, the forward osmosis membrane was produced by using cellulose triacetate (CTA) and cellulose acetate (CA) with polyethylene terephthalate (PET) nonwoven mesh to enhance membrane performance. The preparation conditions including CTA/CA ratio, CTA/CA concentration, casting with/without PET and annealing time were tested for their effects on formation and performance of membranes. The performance of produced membranes was carried out with two filtration systems with dead-end and cross-flow which were employed for the investigation of the water flux, reverse salt flux and specific reverse salt flux. These membranes were tested under two orientations; in the FO mode, the active layer was oriented toward the feed solution whereas, in the PRO mode, the active layer was oriented toward the draw solution. For cross-flow filtration, the operating conditions including flow pattern flow rate and fouling of optimized membrane were studied. SEM and water contact angle analyses showed the CTA/CA membrane has a typical asymmetric three-layered sandwich structure and nonwoven PET was well embedded in the membrane, and the CTA/CA membranes have hydrophilic properties to allow water to penetrate the pore which reflects better water permeation. The result indicated that the optimized membrane with CTA/CA ratio 1:3 under the concentration of CTA/CA 16wt.% has the available water flux and reverse salt flux in cross-flow filtration of 23.88 L/m2.h and 13.62 g/m2.h, respectively. In addition, the membrane was high selectivity properties with the relatively minimal specific reverse salt flux of 0.57 g/L. The performance of the optimal membrane was tested using 1M NaCl draw solution and DI water as the feed solution which both side along with flow rate 520 mL/min in a counter-current pattern. Moreover, the total resistance of the membrane in the PRO mode higher than that in the FO mode.
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