本文主要探討薄膜萃取器中質量傳送速率之改良型修正因子分析。由於薄膜萃取器的質量傳送理論分析可類比於熱交換器的熱量傳送理論，因此利用熱交換器之理論基礎為架構來進行質量傳送系統之理論推導。其討論之要點有:單行程順流、雙行程順流、三行程順流及四行程順流四種的流動方式，而使用體積流率、質傳面積、分配係數和整體質量傳送係數等參數，來繪出方便使用的改良型修正因子圖表，因此，可以不必要使用到繁雜的疊代法，就可以很容易地計算出萃取速率。 理論結果發現:不論進料濃度大小，在四種行程中萃取率的高低，是四行程>三行程>雙行程>單行程。並且可得萃取率與能量消耗率的比較，以單行程為基準，萃取率大約可以提高30%；至於能量消耗率雖然隨著行程數的增加而提高，但其值仍不大。 The expressions of heat- and mass-transfer rates in the multipass heat- and mass-exchangers derived by the conventional correction-factor analysis are implicit and the results should be calculated by using try-and-error method. In the present study, a modified correction-factor analysis was introduced, and the expressions of mass-transfer rate and modified correction-factor charts for membrane extraction in parallel-flow multipass rectangular devices are explicit. The results can be readily calculated without using try-and-error method. The correction factors for multipass operations are plotted in the modified correction-factor charts, they are function of flow rate, mass-transfer-area, distribution coefficient and overall mass-transfer coefficient. Experimental results confirm the predicted values for the extraction of acetic acid from aqueous solution by methyl isobutyl ketone in the double-pass device.
