本研究是在平板掃流式超過濾率統進行實驗，探
討不同溶質(BSA 、Dextran T70 、B-cyclodextrin) 溶液與
不同親疏水性薄膜(PES膜、RCA膜) ，在不同操作參數
(液體速度、pH 值、透膜壓差)下，對濾速、阻隔率、阻
力以及雙溶質溶液分離效率之影響。當溶液與過濾薄膜
之親疏水性質相異時，則粒子與膜面有一排斥作用力存
在。RCA 膜過濾BSA 溶液時，溶質不易在膜面上形成
結垢，因此濾速較高。此時增加掃流速度，對濾速的提
升較為有限。當溶液之pH 值遠離等電點，不僅粒子與
膜面有排斥力外，粒子與粒子問皆有排斥力，導致結垢
層較薄較鬆散，濾速較高。在BSA 與B-cyclodextrin 雙
溶質溶液中，其濾速較純BSA 溶液來得低，此因部份
B-cyclodextrin 進入薄膜孔道形成內部結垢所致，尤其是
在RCA 膜更為明顯。當在PES膜其中，大分子BSA溶質
之親疏水性與薄膜一致時，小分子ß-cyclodextrin 的穿
透率會隨著壓力增加而下降，也造成分離效率的降低。In this study, polymer membranes were
employed in a cross-flow ultrafiltration system to
investigate the effects of solution compositions and
membrane properties on filtration. The solution fluxes,
solute rejections, filtration resistances and separation
selectivity were discussed under various operating
parameters such as liquid velocity, pH value and
transmembrane pressure. The difference in the hydrophobicity between the feed solution and membrane
generates an exclusion force. Such as the case of filtration
of BSA solution by the RCA membrane, a high permeate
flux is achieved due to the solute hard formation of fouling
layer on the membrane surface. When the pH value is far
away the BSA isoelectric point, the porosity of BSA
deposited layer is high due to exclusion between the BSA
molecules and results in high flux. In the binary solutes
system, cause by the internal fouling of cyclodextrin, the
flux of solution containing cyclodextrin is lower than
that of pure BSA solution. On the other, BSA molecules
have strong fouling propensity to PES membrane, the
transmission of cyclodextrin is lowered due to the
compact BSA deposited layer and becomes lower as the
applied pressure increases that will reduce the separation
selectivity.
關聯:
2008年輸送現象及其應用研討會論文摘要集 ( 2008 Symposium of transport phenomena and applications abstract book)
