鋁蝕刻廢液中金屬之移除

Metal Removal from Al Etchant Waste Solution

吳俊誠(Chun-Cheng Wu)

指導教授 ： 顏溪成

國立臺灣大學/工學院/化學工程學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.01811

摘要

本研究主要目標在於將鋁導線蝕刻廢酸液中的鋁離子移除。在本研究中移除蝕刻廢酸液中之鋁離子所使用的實驗方法，主要分為以活性碳電極進行電吸附法及離子交換樹脂法兩種。其中，以活性碳電極進行電吸附法的部分，使用大顆粒型活性碳及活性碳纖維兩者進行實驗，測試電吸附法對鋁離子去除效率，以及包括改變操作電壓、增加含氧官能基、改變陰離子濃度成分等不同變因下的影響。另外亦探討電化學特性輔以分析。實驗結果顯示，活性碳纖維在適當範圍內的外加電位下吸附效果可提升，同時可以改變電位方式控制其脫附。廢液中的鋁錯合離子在正電位下以特定吸附方式被活性碳纖維電極所吸附，在Faradaic反應未起始發生的電位範圍內，+0.5V的外加電位可使活性碳纖維電極達最高鋁吸附容量。而離子交換樹脂法的部分，選用強酸陽離子型交換樹脂，同時含有對多價金屬離子具有高選擇性的螯合官能基。除了探討批次操作與填充床管柱操作的回收效率外，亦對蝕刻廢酸液中所含的氧化劑硝酸根離子造成離子交換樹脂裂解現象、再生樹脂交換效率、以及溫度效應等加以探討。批次操作部分利用縮核模式探討質傳現象，而填充床管柱操作利用BDST模式模擬突破曲線並探討質傳模式。由實驗中得知，離子交換樹脂在濃度稀釋的廢液及常溫下得到較佳的交換效率，超過3wt%的硝酸存在會對樹脂造成侵損。在樹脂中鋁選擇係數平均約為2.93×10-4。

關鍵字

金屬移除 ； 鋁蝕刻廢液 ； 電吸附 ； 離子交換

並列摘要

In this thesis, removal of aluminum ions from aluminum etchant waste solution was performed by electrosorption and ion exchange resins. For electrosorption method by activated carbon, both pellet-type activated carbon and activated carbon fiber (ACF) were used in experiments. Modification approaches on both electrode and electrolyte were tested to support electrosorption behaviors. By taking control of proper applied voltage, adsorption efficiency was found to be raised and desorption operation was also feasible. The results showed that aluminum complex ion was specifically adsorbed on positive-charged ACF electrode and the maximum adsorption capacity was reached at +0.5V applied potential. For ion-exchange method, strong acid cation resin with chelating functional group was used for removal of multivalent metal ion. Both batch and packed-bed column experiments were performed. Then some effects were discussed, such as degradation lead by presence of nitrate ion, temperature effect and concentration effects. Shrinking-core model was used to explain the mass transfer phenomena in batch operation and breakthough curves were also built by experimental data in packed-bed column and modeled by BDST model. The results showed that aluminum complex ion was removed most efficiently in diluted waste at room temperature, and presence of more than 3wt% nitrate ions was harmful to the resin. The estimated selectivity coefficient of Al3+/H+ in the resin was 2.93×10-4 on average.

並列關鍵字

Metal removal ； Al etchant waste solution ； Electrosorption ； Ion exchange

參考文獻

Afkhami, A. and B. Conway. "Investigation of removal of Cr(VI), Mo(VI), W(VI), V(IV), and V(V) oxy-ions from industrial waste-waters by adsorption and electrosorption at high-area carbon cloth," Journal of Colloid and Interface Science 251(2), 248-255 (2002) .

Agrawal, A., K. Sahu, and J. P. Rawat, "Kinetic studies on the exchange of bivalent metal ions on amberlite IRC-718-an iminodiacetate resin," Solvent Extraction and Ion Exchange 21(5), 763-782 (2003).

Alfarra, A., E. Frackowiak, and F. Beguin "Mechanism of lithium electrosorption by activated carbons," Electrochimica Acta 47(10), 1545-1553 (2002).

Alfarra, A., E. Frackowiak, and F. Beguin "The HSAB concept as a means to interpret the adsorption of metal ions onto activated carbons," Applied Surface Science 228(1-4), 84-92 (2004).

Alkire, R. and R. Eisinger, "Electrosorption of organics on flow-through porous-electrodes," Journal of the Electrochemical Society 128(3), C72-C72 (1981).