甲醛對印刷電路板洗液中銅離子交換回收之影響

Effect of Added Formaldehyde on Ion Exchange Recovery of Cu(Ⅱ) from Printed-Circuit-Board Rinse Water

鄧敏慧(Ming-Huei Theng)

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(2004年)

摘要

印刷電路板製程中甲醛是使銅離子還原為銅金屬的重要還原劑，本文主要探討甲醛存在對處理印刷電路板洗液中銅離子交換回收的影響。
離子交換技術廣泛用於移除廢水中的重金屬離子，而形成螯合物的移除效能又受螯合劑與金屬離子形成反應的影響，Cu-EDTA螯合物常見於工業廢水中，本實驗是以陰離子交換樹脂於15℃、25℃、35℃時，在不同pH (1~6)和濃度下(0.5~10 mol/m3) 吸附重金屬-銅。
根據批次平衡交換反應的平衡常數式計算後，可得到反應後的pH值和交換量。在不同溫度(15℃ ~35℃)之實驗發現其交換效果隨著溫度的增加而增加，而且由銅離子平衡交換實驗數據顯示，平衡交換等溫線符合Langmuir模式。另外，經由DHo、DSo及DGo 的計算，其交換平衡為一吸熱反應(DHo>0)且為自發過程(DSo> 0, DGo<0)。

關鍵字

甲醛 ； 離子交換 ； 銅離子

並列摘要

Formaldehyde is reductant that is important to make copper(II) become copper(I) in printed-circuit-board manufacturing process. The aim of this study was to investigate the effect of added formaldehyde on ion exchange recovery of Cu(II) from printed-circuit-board rinse water.
Ion exchange process is well-established method for removal of heavy metal ions from aqueous solutions and widely used in industrial and nuclear wastewater treatment. The Cu-EDTA complexes can often be found in wastewaters. The ion exchange of heavy metals such as copper(II) at different pH (1~6) and concentration (0.5~10 mol/m3) using anion ion exchange resin at 15℃、25℃ and 35℃ was studied.
According to the batch equilibrium experiments, pH value and the amount of metal exchanged were obtained after calculation by the computer program. Thermodynamic parameters were obtained from the experiments of varying temperature (15℃ ~35℃). It was found that an increase in temperature would lead to an increase in ion exchange capacity. The ion exchange equilibrium of copper (II) on to this resin is also investigated to examine the correlations with the Langmuir isotherm. It was indicated the ion exchange process was endoergic reaction (DHo>0) and spontaneous (DSo> 0, DGo<0).

並列關鍵字

Formaldehyde ； Ion Exchange ； copper

參考文獻

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