地表水因易遭受人工汙染，所以具有高含量的有機物質，因此將自來水以輸水管線配送至用戶端前須經過淨化程序。相較於自來水場與傳統淨水處理流程，薄膜過濾技術是新興之高效淨水處理技術，具較簡易得操作與控制以及較低的維護成本。廣泛應用於移除水體中膠體顆粒與微生物的逆滲透(Reverse Osmosis RO)和奈濾(Nanofiltration NF)，可作為現有淨水處理系統的替代或輔助程序。
本研究利用薄膜過濾程序，比較碘、銫及硼的去除效果。研究所使用的平板式薄膜，包含三種超過濾薄膜：DK、DL (GE-OSMONICS, USA)、NF270 (Dow Chemicals, USA)及四種逆滲透薄膜：SG膜 (GE-Osmonics, USA)及UTC膜(UTC_80A、UTC_80C、UTC_80S, Toray, Japan)。超過濾薄膜材質為半芳族聚酰胺，SG膜材質為聚酰胺脂及UTC膜材質為交聯全芳香族聚酰胺。本研究以不同薄膜進行過濾含碘、銫及硼之原水，並觀察其濃度隨時間變化及過濾通量。
研究實驗結果指出，以材質為交聯全芳香族聚酰胺(UTC膜)去除銫及硼的效果最佳，材質為聚酰胺脂(SG膜)去除碘的效果為最佳。因聚酰胺脂(SG膜)為聚乙烯醇（PVA）進行酯化反應，可在選擇性層中具有較強的交聯結構，使得薄膜有較佳的物理支撐力。
部分膜表面改質在本研究中進行探討，例如：氯化、甲殼素沉積與腐植酸塗層。將聚酯酰胺膜 (DL膜) 及半芳族聚酰胺膜 (NF270膜)進行改質，其去除銫的效果可稍微提升。而將交聯全芳香族聚酰胺類的薄膜 (UTC80 及 UTC80A) 及聚酰胺脂膜(DL膜)在鹼性條件下進行改質，對於硼可有較佳的去除率。

Surface water has a high content of organic substances and is exposed to anthropogenic pollutants, thus requiring a high degree of purification before distribution. Compared to conventional water and wastewater treatment systems, membrane separation is a more compact operation that provides higher quality products, easier operational control, and lower maintenance costs. Reverse Osmosis (RO) and nanofiltration (NF), which are widely used to remove colloidal particles and microorganisms, can serve as alternative or supplementary processes to water and wastewater treatment systems.
This study compared performance on iodate, caesium, and boron removal from raw water by means of membrane filtration process. Seven types of flat-sheet membranes, consist of three nanofiltration, DK, DL (GE/Osmonics, USA) and NF270 (Dow Chemicals, USA), and four reverse osmosis membranes, SG (GE/Osmonics, USA) and UTC series membranes, UTC80, UTC80A, and UTC80S (Toray, Japan) were tested in this study. All of the nanofiltration membranes here are semi-aromatic polyamide, while the LPRO and UTC80 series are polyesteramide and cross-linked fully aromatic polyamide membranes, respectively. Permeability, feed flow rate, and the concentration of iodate, caesium, and boron were tested over time.
Cross-linked fully aromatic polyamide membrane gives the best performance in caesium and boron rejection compare to the other kind of membranes. While polyesteramide membrane shows better iodate rejection than semi-aromatic polyamide membrane. Esterification with polyvinyl alcohol (PVA) would contribute to polyesteramide formation resulting in the strongly cross-linked structure in selective layer. This will provide extra physical support together with retention.
As for reflection coefficient value, the closer to one (1), the better solute removal can be obtained by the membrane. This reflection coefficient is depending on solution pH. Means that each membrane has their optimum condition to achieve the best solute removal.
Some modification, such as chlorination, chitosanium deposition, and humic acid coating were conducted in this study. Modification towards caesium removal shows slightly increasing for piperazine-based polyamide membrane (DL and NF270) and gives higher boron removal for cross-linked fully aromatic polyamide membrane (UTC80 and UTC80A) in alkaline conditions.

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