Role of membrane surface morphology in colloidal fouling of cellulose acetate and composite aromatic polyamide reverse osmosis membranes
Role of membrane surface morphology in colloidal fouling of cellulose acetate and composite aromatic polyamide reverse osmosis membranes
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DOI：
10.1016/s0376-7388(96)00351-1
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发表时间：
1997-04-30
影响因子：
9.5
通讯作者：
Hong, SK
中科院分区：
文献类型：
--
作者：
Elimelech, M;Zhu, XH;Hong, SK
采用胶体污染实验，比较了醋酸纤维素和芳香族聚酰胺薄膜复合反渗透膜的污染行为。在相同的初始渗透速率下研究了两种膜的结垢，使得横向流体动力（渗透阻力）对两种膜的结垢的影响是相当的。结果表明，薄膜复合膜的污染速率显着高于醋酸纤维素膜。添加阴离子表面活性剂（十二烷基硫酸钠，SDS）掩模的醋酸纤维素和芳香族聚酰胺膜的化学和电动表面特性的变化，导致只有一个小的变化的污垢行为。薄膜复合膜的更高的结垢延迟归因于表面粗糙度，这是界面聚合的芳族聚酰胺复合膜中固有的。两种膜表面的AFM和SEM图像强烈支持这一结论。这些表面图像揭示了薄膜复合膜表现出大尺度的脊谷结构的表面粗糙度，而醋酸纤维素膜表面相对光滑。
Laboratory-scale colloidal fouling tests, comparing the fouling behavior of cellulose acetate and aromatic polyamide thin-film composite reverse osmosis (RO) membranes, are reported. Fouling of both membranes was studied at identical initial permeation rates so that the effect of the transverse hydrodynamic force (permeation drag) on the fouling of both membranes is comparable. Results showed a significantly higher fouling rate for the thin-film composite membranes compared to that for the cellulose acetate membranes. Addition of an anionic surfactant (sodium dodecyl sulfate, SDS) to mask variations in chemical and electrokinetic surface characteristics of the cellulose acetate and aromatic polyamide membranes resulted in only a small change in the fouling behavior. The higher fouling late for the thin film composite membranes is attributed to surface roughness which is inherent in interfacially polymerized aromatic polyamide composite membranes. AFM and SEM images of the two membrane surfaces strongly support this conclusion. These surface images reveal that the thin-film composite membrane exhibits large-scale surface roughness of ridge-and-valley structure, while the cellulose acetate membrane surface is relatively smooth.