Summary: | 博士 === 淡江大學 === 化學工程與材料工程學系博士班 === 96 === The effects of design and operation parameters on solute mass transfer in three membrane extraction systems, say flat-plate module, tubular module and hollow fiber module, under the concurrent- and countercurrent-flow are investigated theoretically and experimentally. The analytical solution of the two dimensional model is obtained using the separation variable and eigenfunction expansion in terms of power series. The theoretical predictions were represented graphically with the mass-transfer Graetz number (volumetric flow rate), flow pattern, subchannel thickness ratio (permeable-barrier locations) and packing density as parameters and compared with those obtained by numerical approximation and experimental runs. The solute concentration profile, average outlet concentration and mass-transfer efficiency enhancement of the membrane extraction system are also discussed. The experiments in flat-plate module and hollow fiber module are performed to confirm the accuracy of the theoretical results, and the mathematical model derived in the present study was applied to soybean isoflavances to predict the separation efficiency. A RP-HPLC (reversedphase high-performance liquid chromatography) system coupled with an UV detector were utilized to quantify five isoflavances in the extracts. The effect on the amount of five isoflavances of the operation parameters in the cosolvent extraction systems under the hollow fiber modules is also delineated.
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