以錯合-超過濾法自水溶液中去除微量之螯合銅化合物

Removal of Chelated Copper compounds from Dilute Aqueous lution using Complexation-Ultrafiltration method

陳明男(Ming-Nan Chen)

指導教授 ： 莊瑞鑫

元智大學/工程學院/化學工程與材料科學學系/碩士(1994年)

摘要

本論文使用錯合-超過濾程序，自稀溶液中去除螯合銅化合物，主要利用
在其水溶液下添加水溶性電解質聚乙烯亞胺 (Polyethyleneimine，PEI）
之水溶性電解質，使其與螯合銅化合物形成錯合物，然後再以超過濾分離
。螯合劑選用二乙胺四乙酸（Ethylenediaminetetraacetic acid，EDTA
）及三乙酸基氨（Nitrilotriacetic acid，NTA）。首先測定純 PEI、螯
合銅等之超過濾去除率，以了解各物質個別之去除效果。接著，改變薄膜
的材質與孔徑大小、操作壓力、溶液之 pH 值、添加鹽類及溶液中聚乙烯
亞胺、螯合劑及銅離子三者之濃度比值等變數，測定 PEI/螯合銅系統之
去除率及透過液流速，由此可得知，此分離操作的最佳條件。同時，由透
過液的流速變化可測得修正結垢值指數（Modified fouling index），以
了解超過濾時薄膜的結垢現象；再測試其他重金屬（Ni2+，Zn2+， Co2+
等）， pH 值與去除率之關係。理論模式利用化學平衡與質量平衡，理論
模式可得 PEI 與H+結合常數（K1），金屬離子、螯合金屬與 PEI 結合常
數（K0、K10）及平均結合計量係數（n）。最後，測試PEI再生回收之可
能性及操作條件。

關鍵字

錯合超過濾 ； 聚電解質 ； 螯合銅

並列摘要

In this paper, a compexation-ultrafiltation (UF) process was
proposed to check the feasibility for removing copper-chelated
compounds after their complexation with water-soluble polymers
(polyelectrolytes). The chelating agents used was
ethylenediaminetetraacetic acid (EDTA) and nitrilotri -acetic
acid (NTA), and the polyelectrolyte was polyethyleneimine
(PEI), a weak base. The rejection coefficient of pure PEI, Cu(
II), Cu-EDTA and Cu-NTA chelates were measured. Then , the
rejection coefficient and UF flux were also measured for the
systems of PEI/Cu(II), PEI/Cu-EDTA, and PEI/Cu-NTA by changing
the parameters including membrane material and pore size, the
applied pressure, the aqueous pH, the salt added , and the
concentration ratio of PEI/chelating agent/Cu(II). In this
instance, the optimal removal conditions was obtained and the
fouling of membrane during UF was identified by modified
fouling index (MFI) form flux data. The same UF test carried
out to obtain the relation between pH and rejection
coefficient. these results were applied to determined several
equilibibrium constants of PEI-H+, metal-PEI, metal-chelated-
PEI are calculated by in accoordination for complexation. The
regeneration and reuse of PEI was also studied and the
feasibility of such complexation -UF process for the removal of
metal-chelated compounds was discussed .

並列關鍵字

polyelectrolytes ； chelated-copper ； UF